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Sample records for bipolar transistor hbt

  1. Performance enhancement of a heterojunction bipolar transistor (HBT) by two-step passivation

    International Nuclear Information System (INIS)

    Fu, S.-I.; Lai, P.-H.; Tsai, Y.-Y.; Hung, C.-W.; Yen, C.-H.; Cheng, S.-Y.; Liu, W.-C.

    2006-01-01

    An interesting two-step passivation (with ledge structure and sulphide based chemical treatment) on base surface, for the first time, is demonstrated to study the temperature-dependent DC characteristics and noise performance of an InGaP/GaAs heterojunction bipolar transistor (HBT). Improved transistor behaviors on maximum current gain β max , offset voltage ΔV CE , and emitter size effect are obtained by using the two-step passivation. Moreover, the device with the two-step passivation exhibits relatively temperature-independent and improved thermal stable performances as the temperature is increased. Therefore, the two-step passivationed device can be used for high-temperature and low-power electronics applications

  2. Cryogenic preamplification of a single-electron-transistor using a silicon-germanium heterojunction-bipolar-transistor

    Energy Technology Data Exchange (ETDEWEB)

    Curry, M. J. [Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Center for Quantum Information and Control, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Sandia National Laboratories, 1515 Eubank Blvd SE, Albuquerque, New Mexico 87123 (United States); England, T. D.; Bishop, N. C.; Ten-Eyck, G.; Wendt, J. R.; Pluym, T.; Lilly, M. P.; Carroll, M. S. [Sandia National Laboratories, 1515 Eubank Blvd SE, Albuquerque, New Mexico 87123 (United States); Carr, S. M. [Center for Quantum Information and Control, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Sandia National Laboratories, 1515 Eubank Blvd SE, Albuquerque, New Mexico 87123 (United States)

    2015-05-18

    We examine a silicon-germanium heterojunction bipolar transistor (HBT) for cryogenic pre-amplification of a single electron transistor (SET). The SET current modulates the base current of the HBT directly. The HBT-SET circuit is immersed in liquid helium, and its frequency response from low frequency to several MHz is measured. The current gain and the noise spectrum with the HBT result in a signal-to-noise-ratio (SNR) that is a factor of 10–100 larger than without the HBT at lower frequencies. The transition frequency defined by SNR = 1 has been extended by as much as a factor of 10 compared to without the HBT amplification. The power dissipated by the HBT cryogenic pre-amplifier is approximately 5 nW to 5 μW for the investigated range of operation. The circuit is also operated in a single electron charge read-out configuration in the time-domain as a proof-of-principle demonstration of the amplification approach for single spin read-out.

  3. InP Heterojunction Bipolar Transistor Amplifiers to 255 GHz

    Science.gov (United States)

    Radisic, Vesna; Sawdai, Donald; Scott, Dennis; Deal, William; Dang, Linh; Li, Danny; Cavus, Abdullah; To, Richard; Lai, Richard

    2009-01-01

    Two single-stage InP heterojunction bipolar transistor (HBT) amplifiers operate at 184 and 255 GHz, using Northrop Grumman Corporation s InP HBT MMIC (monolithic microwave integrated circuit) technology. At the time of this reporting, these are reported to be the highest HBT amplifiers ever created. The purpose of the amplifier design is to evaluate the technology capability for high-frequency designs and verify the model for future development work.

  4. Measurement of low-frequency base and collector current noise and coherence in SiGe heterojunction bipolar transistors using transimpedance amplifiers

    NARCIS (Netherlands)

    Bruce, S.P.O.; Vandamme, L.K.J.; Rydberg, A.

    1999-01-01

    Transimpedance amplifiers have been used for direct study of current noise in silicon germanium (SiGe) heterojunction bipolar transistors (HBT's) at different biasing conditions. This has facilitated a wider range of resistances in the measurement circuit around the transistor than is possible when

  5. High-performance indium gallium phosphide/gallium arsenide heterojunction bipolar transistors

    Science.gov (United States)

    Ahmari, David Abbas

    Heterojunction bipolar transistors (HBTs) have demonstrated the high-frequency characteristics as well as the high linearity, gain, and power efficiency necessary to make them attractive for a variety of applications. Specific applications for which HBTs are well suited include amplifiers, analog-to-digital converters, current sources, and optoelectronic integrated circuits. Currently, most commercially available HBT-based integrated circuits employ the AlGaAs/GaAs material system in applications such as a 4-GHz gain block used in wireless phones. As modern systems require higher-performance and lower-cost devices, HBTs utilizing the newer, InGaP/GaAs and InP/InGaAs material systems will begin to dominate the HBT market. To enable the widespread use of InGaP/GaAs HBTs, much research on the fabrication, performance, and characterization of these devices is required. This dissertation will discuss the design and implementation of high-performance InGaP/GaAs HBTs as well as study HBT device physics and characterization.

  6. The Aluminum-Free P-n-P InGaAsN Double Heterojunction Bipolar Transistors

    Energy Technology Data Exchange (ETDEWEB)

    CHANG,PING-CHIH; LI,N.Y.; BACA,ALBERT G.; MONIER,C.; LAROCHE,J.R.; HOU,H.Q.; REN,F.; PEARTON,S.J.

    2000-08-01

    The authors have demonstrated an aluminum-free P-n-P GaAs/InGaAsN/GaAs double heterojunction bipolar transistor (DHBT). The device has a low turn-on voltage (V{sub ON}) that is 0.27 V lower than in a comparable P-n-p AlGaAs/GaAs HBT. The device shows near-ideal D. C. characteristics with a current gain ({beta}) greater than 45. The high-speed performance of the device are comparable to a similar P-n-p AlGaAs/GaAs HBT, with f{sub T} and f{sub MAX} values of 12 GHz and 10 GHz, respectively. This device is very suitable for low-power complementary HBT circuit applications, while the aluminum-free emitter structure eliminates issues typically associated with AlGaAs.

  7. Optical Sensitivity of a Monolithic Integrated InP PIN-HEMT-HBT Transimpedance Amplifier

    OpenAIRE

    Matiss, A.; Janssen, G.; Bertenburg, R. M.; Brockerhoff, W.; Tegude, F.J.

    2004-01-01

    To improve sensitivity of optical receivers, a special integration concept is chosen that includes a pinphotodiode, high-electron mobility transistors (HEMT) and heterostructure bipolar transistors (HBT) on a single substrate. This work focuses on the optimization of the amplifier design to achieve lowest input noise currents of a transimpedance amplifier, and thus highest receiver sensitivity. The respective advantages of the components used are investigated with respect...

  8. An InP HBT sub-harmonic mixer for E-band wireless communication

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Krozer, Viktor

    2010-01-01

    This paper reports on a novel balanced HBT subharmonic mixer (SHM) for E-band wireless communication. An LO spiral type Marchand balun is integrated with the SHM. The SHM has been fabricated in a InP double heterojunction bipolar transistor (DHBT) circuit-oriented technology with fT /fmax = 180GHz...

  9. SiGe HBT cryogenic preamplification for higher bandwidth donor spin read-out

    Science.gov (United States)

    Curry, Matthew; Carr, Stephen; Ten-Eyck, Greg; Wendt, Joel; Pluym, Tammy; Lilly, Michael; Carroll, Malcolm

    2014-03-01

    Single-shot read-out of a donor spin can be performed using the response of a single-electron-transistor (SET). This technique can produce relatively large changes in current, on the order of 1 (nA), to distinguish between the spin states. Despite the relatively large signal, the read-out time resolution has been limited to approximately 100 (kHz) of bandwidth because of noise. Cryogenic pre-amplification has been shown to extend the response of certain detection circuits to shorter time resolution and thus higher bandwidth. We examine a SiGe HBT circuit configuration for cryogenic preamplification, which has potential advantages over commonly used HEMT configurations. Here we present 4 (K) measurements of a circuit consisting of a Silicon-SET inline with a Heterojunction-Bipolar-Transistor (HBT). We compare the measured bandwidth with and without the HBT inline and find that at higher frequencies the signal-to-noise-ratio (SNR) with the HBT inline exceeds the SNR without the HBT inline. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE, Office of Basic Energy Sciences user facility. The work was supported by the Sandia National Laboratories Directed Research and Development Program. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000.

  10. Thermal resistance matrix representation of thermal effects and thermal design in multi-finger power heterojunction bipolar transistors

    Institute of Scientific and Technical Information of China (English)

    Jin Dong-Yue; Zhang Wan-Rong; Chen Liang; Fu Qiang; Xiao Ying; Wang Ren-Qing; Zhao Xin

    2011-01-01

    The thermal resistance matrix including self-heating thermal resistance and thermal coupling resistance is presented to describe the thermal effects of multi-finger power heterojunction bipolar transistors. The dependence of thermal resistance matrix on finger spacing is also investigated. It is shown that both self-heating thermal resistance and thermal coupling resistance are lowered by increasing the finger spacing, in which the downward dissipated heat path is widened and the heat flow from adjacent fingers is effectively suppressed. The decrease of self-heating thermal resistance and thermal coupling resistance is helpful for improving the thermal stability of power devices. Furthermore, with the aid of the thermal resistance matrix, a 10-finger power heterojunction bipolar transistor (HBT) with non-uniform finger spacing is designed for high thermal stability. The optimized structure can effectively lower the peak temperature while maintaining a uniformity of the temperature profile at various biases and thus the device effectively may operate at a higher power level.

  11. DC modeling and characterization of AlGaAs/GaAs heterojunction bipolar transistors for high-temperature applications

    International Nuclear Information System (INIS)

    Dikmen, C.T.; Dogan, N.S.; Osman, M.A.

    1994-01-01

    There is currently a demand for active electronic devices operating reliably over wide range of temperatures. Potential applications for the high-temperature devices and integrated circuits are in the areas of jet engine and control instrumentation for nuclear power plants. Here, the large signal dc characteristics of AlGaAs/GaAs heterojunction bipolar transistors (HBT) at high temperatures (27--300 C) are reported. A high-temperature SPICE model is developed which includes the recombination-generation current components and avalanche multiplication which become extremely important at high temperatures. The effect of avalanche breakdown is also included to model the current due to thermal generation of electron/hole pairs causing breakdown at high temperatures. A parameter extraction program is developed used to extract the model parameters of HBT's at different temperatures. Fitting functions for the model parameters as a function of temperature are developed. These parameters are then used in the SPICE Ebers-Moll model for the dc characterization of the HBT at any temperature between (27--300 C)

  12. Measurement, modeling, and simulation of cryogenic SiGe HBT amplifier circuits for fast single spin readout

    Science.gov (United States)

    England, Troy; Curry, Matthew; Carr, Steve; Swartzentruber, Brian; Lilly, Michael; Bishop, Nathan; Carrol, Malcolm

    2015-03-01

    Fast, low-power quantum state readout is one of many challenges facing quantum information processing. Single electron transistors (SETs) are potentially fast, sensitive detectors for performing spin readout of electrons bound to Si:P donors. From a circuit perspective, however, their output impedance and nonlinear conductance are ill suited to drive the parasitic capacitance typical of coaxial conductors used in cryogenic environments, necessitating a cryogenic amplification stage. We will discuss calibration data, as well as modeling and simulation of cryogenic silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) circuits connected to a silicon SET and operating at 4 K. We find a continuum of solutions from simple, single-HBT amplifiers to more complex, multi-HBT circuits suitable for integration, with varying noise levels and power vs. bandwidth tradeoffs. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000.

  13. Wide bandgap collector III-V double heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Flitcroft, R.M.

    2000-10-01

    This thesis is devoted to the study and development of Heterojunction Bipolar Transistors (HBTs) designed for high voltage operation. The work concentrates on the use of wide bandgap III-V semiconductor materials as the collector material and their associated properties influencing breakdown, such as impact ionisation coefficients. The work deals with issues related to incorporating a wide bandgap collector into double heterojunction structures such as conduction band discontinuities at the base-collector junction and results are presented which detail, a number of methods designed to eliminate the effects of such discontinuities. In particular the use of AlGaAs as the base material has been successful in eliminating the conduction band spike at this interface. A method of electrically injecting electrons into the collector has been employed to investigate impact ionisation in GaAs, GaInP and AlInP which has used the intrinsic gain of the devices to extract impact ionisation coefficients over a range of electric fields beyond the scope of conventional optical injection techniques. This data has enabled the study of ''dead space'' effects in HBT collectors and have been used to develop an analytical model of impact ionisation which has been incorporated into an existing Ebers-Moll HBT simulator. This simulator has been shown to accurately reproduce current-voltage characteristics in both the devices used in this work and for external clients. (author)

  14. InGaP/InGaAsN/GaAs NpN double-heterojunction bipolar transistor

    International Nuclear Information System (INIS)

    Chang, P. C.; Baca, A. G.; Li, N. Y.; Xie, X. M.; Hou, H. Q.; Armour, E.

    2000-01-01

    We have demonstrated a functional NpN double-heterojunction bipolar transistor (DHBT) using InGaAsN for the base layer. The InGaP/In 0.03 Ga 0.97 As 0.99 N 0.01 /GaAs DHBT has a low V ON of 0.81 V, which is 0.13 V lower than in a InGaP/GaAs heterojunction bipolar transistor (HBT). The lower turn-on voltage is attributed to the smaller band gap (1.20 eV) of metalorganic chemical vapor deposition-grown In 0.03 Ga 0.97 As 0.99 N 0.01 base layer. GaAs is used for the collector; thus the breakdown voltage (BV CEO ) is 10 V, consistent with the BV CEO of InGaP/GaAs HBTs of comparable collector thickness and doping level. To alleviate the current blocking phenomenon caused by the larger conduction band discontinuity between InGaAsN and GaAs, a graded InGaAs layer with δ doping is inserted at the base-collector junction. The improved device has a peak current gain of seven with ideal current-voltage characteristics. (c) 2000 American Institute of Physics

  15. Cryogenic operation of a 24 GHz MMIC SiGe HBT medium power amplifier

    International Nuclear Information System (INIS)

    Qin, Guoxuan; Jiang, Ningyue; Seo, Jung-Hun; Cho, Namki; Van der Weide, Daniel; Ma, Zhenqiang; Ponchak, George E; Ma, Pingxi; Stetson, Scott; Racanelli, Marco

    2010-01-01

    The performance of a SiGe heterojunction bipolar transistor (HBT) millimetre-wave power amplifier (PA) operating at cryogenic temperature was reported and analysed for the first time. A 24 GHz two-stage medium PA employing common-emitter and common-base SiGe power HBTs in the first and the second stage, respectively, showed a significant power gain increase at 77 K in comparison with that measured at room temperature. Detailed analyses indicate that cryogenic operation of SiGe HBT-based PAs mainly affects (improves) the performance of the SiGe HBTs in the circuits due to transconductance enhancement through magnified, favourable changes of SiGe bandgap due to cooling (ΔE g /kT) and minimized thermal effects, with little influence on the passive components of the circuits

  16. Dose enhancement effects of X ray radiation in bipolar transistors

    International Nuclear Information System (INIS)

    Chen Panxun

    1997-01-01

    The author has presented behaviour degradation and dose enhancement effects of bipolar transistors in X ray irradiation environment. The relative dose enhancement factors of X ray radiation were measured in bipolar transistors by the experiment methods. The mechanism of bipolar device dose enhancement was investigated

  17. Characteristics of Novel InGaAsN Double Heterojunction Bipolar Transistors

    Energy Technology Data Exchange (ETDEWEB)

    LI,N.Y.; CHANG,PING-CHIH; BACA,ALBERT G.; LAROCHE,J.R.; REN,F.; ARMOUR,E.; SHARPS,P.R.; HOU,H.Q.

    2000-08-01

    The authors demonstrate, for the first time, both functional Pnp AlGaAs/InGaAsN/GaAs (Pnp InGaAsN) and Npn InGaP/InGaAsN/GaAs (Npn InGaAsN) double heterojunction bipolar transistors (DHBTs) using a 1.2 eV In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01} as the base layer for low-power electronic applications. The Pnp InGaAsN DHBT has a peak current gain ({beta}) of 25 and a low turn-on voltage (V{sub ON}) of 0.79 V. This low V{sub ON} is {approximately} 0.25 V lower than in a comparable Pnp AlGAAs/GaAs HBT. For the Npn InGaAsN DHBT, it has a low V{sub ON} of 0.81 V, which is 0.13 V lower than in an InGaP/GaAs HBT. A peak {beta} of 7 with nearly ideal I-V characteristics has been demonstrated. Since GaAs is used as the collector of both Npn and Pnp InGaAsN DHBTs, the emitter-collector breakdown voltage (BV{sub CEO}) are 10 and 12 V, respectively, consistent with the BV{sub CEO} of Npn InGaP/GaAs and Pnp AlGaAs/GaAs HBTs of comparable collector thickness and doping level. All these results demonstrate the potential of InGaAsN DHBTs as an alternative for application in low-power electronics.

  18. Study on ionizing radiation effects of bipolar transistor with BPSG films

    International Nuclear Information System (INIS)

    Lu Man; Zhang Xiaoling; Xie Xuesong; Sun Jiangchao; Wang Pengpeng; Lu Changzhi; Zhang Yanxiu

    2013-01-01

    Background: Because of the damage induced by ionizing radiation, bipolar transistors in integrated voltage regulator could induce the current gain degradation and increase leakage current. This will bring serious problems to electronic system. Purpose: In order to ensure the reliability of the device work in the radiation environments, the device irradiation reinforcement technology is used. Methods: The characteristics of 60 Co γ irradiation and annealing at different temperatures in bipolar transistors and voltage regulators (JW117) with different passive films for SiO 2 +BPSG+SiO 2 and SiO 2 +SiN have been investigated. Results: The devices with BPSG film enhanced radiation tolerance significantly. Because BPSG films have better absorption for Na + in SiO 2 layer, the surface recombination rate of base region in a bipolar transistor and the excess base current have been reduced. It may be the main reason for BJT with BPSG film having a good radiation hardness. And annealing experiments at different temperatures after irradiation ensure the reliability of the devices with BPSG films. Conclusions: A method of improving the ionizing irradiation hardness of bipolar transistors is proposed. As well as the linear integrated circuits which containing bipolar transistors, an experimental basis for the anti-ionizing radiation effects of bipolar transistors is provided. (authors)

  19. Flexible Low-power SiGe HBT Amplifier Circuits for Fast Single-shot Spin Readout

    Science.gov (United States)

    England, Troy; Lilly, Michael; Curry, Matthew; Carr, Stephen; Carroll, Malcolm

    Fast, low-power quantum state readout is one of many challenges facing quantum information processing. Single electron transistors (SETs) are potentially fast, sensitive detectors for performing spin readout of electrons bound to Si:P donors. From a circuit perspective, however, their output impedance and nonlinear conductance are ill suited to drive the parasitic capacitance of coaxial conductors used in cryogenic environments, necessitating a cryogenic amplification stage. We will introduce two new amplifier topologies that provide excellent gain versus power tradeoffs using silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs). The AC HBT allows in-situ adjustment of power dissipation during an experiment and can provide gain in the millikelvin temperature regime while dissipating less than 500 nW. The AC Current Amplifier maximizes gain at nearly 800 A/A. We will also show results of using these amplifiers with SETs at 4 K. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000. Flexible Low-power SiGe HBT Amplifier Circuits for Fast Single-shot Spin Readout.

  20. Recent advances in understanding total-dose effects in bipolar transistors

    International Nuclear Information System (INIS)

    Schrimpf, R.D.

    1996-01-01

    Gain degradation in irradiated bipolar transistors can be a significant problem, particularly in linear integrated circuits. In many bipolar technologies, the degradation is greater for irradiation at low dose rates than it is for typical laboratory dose rates. Ionizing radiation causes the base current in bipolar transistors to increase, due to the presence of net positive charge in the oxides covering sensitive device areas and increases in surface recombination velocity. Understanding the mechanisms responsible for radiation-induced gain degradation in bipolar transistors is important in developing appropriate hardness assurance methods. This paper reviews recent modeling and experimental work, with the emphasis on low-dose-rate effects. A promising hardness assurance method based on irradiation at elevated temperatures is described

  1. The effect and mechanism of the bipolar junction transistor in different temperature

    International Nuclear Information System (INIS)

    Wang Dong; Lu Wu; Ren Diyuan; Li Aiwu; Kuang Zhibing

    2007-01-01

    The annealing-effect of bipolar junction transistor in different temperature is investigated. It is found that the anneal of the bipolar transistor is related to the annealing-temperature, and the annealing-effect of the different type transistor is dissimilar. The possible mechanism is discussed. (authors)

  2. Single-event burnout of epitaxial bipolar transistors

    Energy Technology Data Exchange (ETDEWEB)

    Kuboyama, S.; Sugimoto, K.; Shugyo, S.; Matsuda, S. [National Space Development Agency of Japan, Tsukuba, Ibaraki (Japan); Hirao, T. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan)

    1998-12-01

    Single-Event Burnout (SEB) of bipolar junction transistors (BJTs) has been observed nondestructively. It was revealed that all the NPN BJTs, including small signal transistors, with thinner epitaxial layers were inherently susceptible to the SEB phenomenon. It was demonstrated that several design parameters of BJTs were responsible for SEB susceptibility. Additionally, destructive and nondestructive modes of SEB were identified.

  3. Single-event burnout of epitaxial bipolar transistors

    Energy Technology Data Exchange (ETDEWEB)

    Kuboyama, Satoshi; Sugimoto, Kenji; Matsuda, Sumio [National Space Development Agency of Japan, Ysukuba, Ibaraki (Japan); Hirao, Toshio

    1998-10-01

    Single-event burnout (SEB) of bipolar junction transistors (BJTs) has been observed nondestructively. It was revealed that all the NPN BJTs including small signal transistors with thinner epitaxial layer were inherently susceptible to the SEB phenomenon. It was demonstrated that several design parameters of BJTs were responsible for SEB susceptibility. Additionally, destructive and nondestructive modes of SEB were identified. (author)

  4. A high linearity SiGe HBT LNA for GPS receiver

    International Nuclear Information System (INIS)

    Luo Yanbin; Shi Jian; Ma Chengyan; Gan Yebing; Qian Min

    2014-01-01

    A high linearity 1.575 GHz SiGe:HBT low noise amplifier (LNA) for global positioning system applications is described. The bipolar cascoded with an MOSFET LNA was fabricated in a commercial 0.18 μm SiGe BiCMOS process. A resistor bias feed circuit with a feedback resistor was designed for the LNA input transistor to improve its intermodulation and compression performance. The packaged chip tested on board has displayed a noise figure of 1.11 dB, a power gain of 18 dB, an output 1 dB compression point of +7.8 dBm and an input third-order intercept point of +1.8 dBm. The chip occupies a 500 × 560 μm 2 area and consumes 3.6 mA from a 2.85 V power supply. (semiconductor integrated circuits)

  5. Impact of Process Technologies on ELDRS of Bipolar Transistors

    International Nuclear Information System (INIS)

    Lu Wu; Ren Diyuan; Guo Qi; Yu Xuefeng; Zheng Yuzhan

    2010-01-01

    Radiation effects under different dose rates and annealing behaviors of domestic bipolar transistors, with same manufacture technology, were investigated.These transistors include NPN transistors of various emitter area, and LPNP transistors with different doping concentrations in emitter. It is shown that different types of transistors have different radiation responses. The results of NPN transistors show that more degradation occurs at less emitter area. Yet, the results of LPNP transistors demonstrate that transistors with lightly doped emitter are more sensitive to radiation, compared with heavily doped emitter. Finally,the mechanisms of the difference between various radiation responses were analyzed. (authors)

  6. A high-linearity InGaP/GaAs HBT power amplifier for IEEE 802.11a/n

    International Nuclear Information System (INIS)

    Cui Jie; Chen Lei; Kang Chunlei; Shi Jia; Zhang Xuguang; Ai Baoli; Liu Yi

    2013-01-01

    A three-stage 4.8–6 GHz monolithic power amplifier (PA) compatible with IEEE 802.11a/n designed based on an advanced 2 μm InGaP/GaAs hetero-junction bipolar transistor (HBT) process is presented. The PA integrates input matching and closed-loop power control circuits on chip. Under 3.3 V DC bias, the amplifier achieves a ∼31 dB small signal gain, excellent wide band input and output matching among overall 1.2 GHz bandwidth, and up to 24.5 dBm linear output power below EVM 3% with IEEE 802.11a 64QAM OFDM input signal. (semiconductor integrated circuits)

  7. Radiation induced deep level defects in bipolar junction transistors under various bias conditions

    International Nuclear Information System (INIS)

    Liu, Chaoming; Yang, Jianqun; Li, Xingji; Ma, Guoliang; Xiao, Liyi; Bollmann, Joachim

    2015-01-01

    Bipolar junction transistor (BJT) is sensitive to ionization and displacement radiation effects in space. In this paper, 35 MeV Si ions were used as irradiation source to research the radiation damage on NPN and PNP bipolar transistors. The changing of electrical parameters of transistors was in situ measured with increasing irradiation fluence of 35 MeV Si ions. Using deep level transient spectroscopy (DLTS), defects in the bipolar junction transistors under various bias conditions are measured after irradiation. Based on the in situ electrical measurement and DLTS spectra, it is clearly that the bias conditions can affect the concentration of deep level defects, and the radiation damage induced by heavy ions.

  8. The effects of gamma irradiation on neutron displacement sensitivity of lateral PNP bipolar transistors

    International Nuclear Information System (INIS)

    Wang, Chenhui; Chen, Wei; Liu, Yan; Jin, Xiaoming; Yang, Shanchao; Qi, Chao

    2016-01-01

    The effects of gamma irradiation on neutron displacement sensitivity of four types of lateral PNP bipolar transistors (LPNPs) with different neutral base widths, emitter widths and the doping concentrations of the epitaxial base region are studied. The physical mechanisms of the effects are explored by defect analysis using deep level transient spectroscopy (DLTS) techniques and numerical simulations of recombination process in the base region of the lateral PNP bipolar transistors, and are verified by the experiments on gate-controlled lateral PNP bipolar transistors (GCLPNPs) manufactured in the identical commercial bipolar process with different gate bias voltage. The results indicate that gamma irradiation increases neutron displacement damage sensitivity of lateral PNP bipolar transistors and the mechanism of this phenomenon is that positive charge induced by gamma irradiation enhances the recombination process in the defects induced by neutrons in the base region, leading to larger recombination component of base current and greater gain degradation.

  9. The effects of gamma irradiation on neutron displacement sensitivity of lateral PNP bipolar transistors

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chenhui, E-mail: wangchenhui@nint.ac.cn; Chen, Wei; Liu, Yan; Jin, Xiaoming; Yang, Shanchao; Qi, Chao

    2016-09-21

    The effects of gamma irradiation on neutron displacement sensitivity of four types of lateral PNP bipolar transistors (LPNPs) with different neutral base widths, emitter widths and the doping concentrations of the epitaxial base region are studied. The physical mechanisms of the effects are explored by defect analysis using deep level transient spectroscopy (DLTS) techniques and numerical simulations of recombination process in the base region of the lateral PNP bipolar transistors, and are verified by the experiments on gate-controlled lateral PNP bipolar transistors (GCLPNPs) manufactured in the identical commercial bipolar process with different gate bias voltage. The results indicate that gamma irradiation increases neutron displacement damage sensitivity of lateral PNP bipolar transistors and the mechanism of this phenomenon is that positive charge induced by gamma irradiation enhances the recombination process in the defects induced by neutrons in the base region, leading to larger recombination component of base current and greater gain degradation.

  10. Shootthrough fault protection system for bipolar transistors in a voltage source transistor inverter

    International Nuclear Information System (INIS)

    Wirth, W.F.

    1982-01-01

    Faulted bipolar transistors in a voltage source transistor inverter are protected against shootthrough fault current, from the filter capacitor of the d-c voltage source which drives the inverter over the d-c bus, by interposing a small choke in series with the filter capacitor to limit the rate of rise of that fault current while at the same time causing the d-c bus voltage to instantly drop to essentially zero volts at the beginning of a shootthrough fault. In this way, the load lines of the faulted transistors are effectively shaped so that they do not enter the second breakdown area, thereby preventing second breakdown destruction of the transistors

  11. Radiation effects on junction field-effect transistors (JFETS), MOSFETs, and bipolar transistors, as related to SSC circuit design

    International Nuclear Information System (INIS)

    Kennedy, E.J.; Alley, G.T.; Britton, C.L. Jr.; Skubic, P.L.; Gray, B.; Wu, A.

    1990-01-01

    Some results of radiation effects on selected junction field-effect transistors, MOS field-effect transistors, and bipolar junction transistors are presented. The evaluations include dc parameters, as well as capacitive variations and noise evaluations. The tests are made at the low current and voltage levels (in particular, at currents ≤1 mA) that are essential for the low-power regimes required by SSC circuitry. Detailed noise data are presented both before and after 5-Mrad (gamma) total-dose exposure. SPICE radiation models for three high-frequency bipolar processes are compared for a typical charge-sensitive preamplifier

  12. Application of accelerated simulation method on NPN bipolar transistors of different technology

    International Nuclear Information System (INIS)

    Fei Wuxiong; Zheng Yuzhan; Wang Yiyuan; Chen Rui; Li Maoshun; Lan Bo; Cui Jiangwei; Zhao Yun; Lu Wu; Ren Diyuan; Wang Zhikuan; Yang Yonghui

    2010-01-01

    With different radiation methods, ionizing radiation response of NPN bipolar transistors of six different processes was investigated. The results show that the enhanced low dose rate sensitivity obviously exists in NPN bipolar transistors of the six kinds of processes. According to the experiment, the damage of decreasing temperature in step during irradiation is obviously greater than the result of irradiated at high dose rate. This irradiation method can perfectly simulate and conservatively evaluate low dose rate damage, which is of great significance to radiation effects research of bipolar devices. Finally, the mechanisms of the experimental phenomena were analyzed. (authors)

  13. Broad Beam and Ion Microprobe Studies of Single-Event Upsets in High Speed 0.18micron Silicon Germanium Heterojunction Bipolar Transistors and Circuits

    Science.gov (United States)

    Reed, Robert A.; Marshall, Paul W.; Pickel, Jim; Carts, Martin A.; Irwin, TIm; Niu, Guofu; Cressler, John; Krithivasan, Ramkumar; Fritz, Karl; Riggs, Pam

    2003-01-01

    SiGe based technology is widely recognized for its tremendous potential to impact the high speed microelectronic industry, and therefore the space industry, by monolithic incorporation of low power complementary logic with extremely high speed SiGe Heterojunction Bipolar Transistor (HBT) logic. A variety of studies have examined the ionizing dose, displacement damage and single event characteristics, and are reported. Accessibility to SiGe through an increasing number of manufacturers adds to the importance of understanding its intrinsic radiation characteristics, and in particular the single event effect (SEE) characteristics of the high bandwidth HBT based circuits. IBM is now manufacturing in its 3rd generation of their commercial SiGe processes, and access is currently available to the first two generations (known as and 6HP) through the MOSIS shared mask services with anticipated future release of the latest (7HP) process. The 5 HP process is described and is characterized by a emitter spacing of 0.5 micron and a cutoff frequency ff of 50 GHz, whereas the fully scaled 7HP HBT employs a 0.18 micron emitter and has an fT of 120 GHz. Previous investigations have the examined SEE response of 5 HP HBT circuits through both circuit testing and modeling. Charge collection modeling studies in the 5 H P process have also been conducted, but to date no measurements have been reported of charge collection in any SiGe HBT structures. Nor have circuit models for charge collection been developed in any version other than the 5 HP HBT structure. Our investigation reports the first indications of both charge collection and circuit response in IBM s 7HP-based SiGe process. We compare broad beam heavy ion SEU test results in a fully function Pseudo-Random Number (PRN) sequence generator up to frequencies of 12 Gbps versus effective LET, and also report proton test results in the same circuit. In addition, we examine the charge collection characteristics of individual 7HP HBT

  14. Modeling of charge transport in ion bipolar junction transistors.

    Science.gov (United States)

    Volkov, Anton V; Tybrandt, Klas; Berggren, Magnus; Zozoulenko, Igor V

    2014-06-17

    Spatiotemporal control of the complex chemical microenvironment is of great importance to many fields within life science. One way to facilitate such control is to construct delivery circuits, comprising arrays of dispensing outlets, for ions and charged biomolecules based on ionic transistors. This allows for addressability of ionic signals, which opens up for spatiotemporally controlled delivery in a highly complex manner. One class of ionic transistors, the ion bipolar junction transistors (IBJTs), is especially attractive for these applications because these transistors are functional at physiological conditions and have been employed to modulate the delivery of neurotransmitters to regulate signaling in neuronal cells. Further, the first integrated complementary ionic circuits were recently developed on the basis of these ionic transistors. However, a detailed understanding of the device physics of these transistors is still lacking and hampers further development of components and circuits. Here, we report on the modeling of IBJTs using Poisson's and Nernst-Planck equations and the finite element method. A two-dimensional model of the device is employed that successfully reproduces the main characteristics of the measurement data. On the basis of the detailed concentration and potential profiles provided by the model, the different modes of operation of the transistor are analyzed as well as the transitions between the different modes. The model correctly predicts the measured threshold voltage, which is explained in terms of membrane potentials. All in all, the results provide the basis for a detailed understanding of IBJT operation. This new knowledge is employed to discuss potential improvements of ion bipolar junction transistors in terms of miniaturization and device parameters.

  15. Degradation Mechanisms for GaN and GaAs High Speed Transistors

    Directory of Open Access Journals (Sweden)

    Fan Ren

    2012-11-01

    Full Text Available We present a review of reliability issues in AlGaN/GaN and AlGaAs/GaAs high electron mobility transistors (HEMTs as well as Heterojunction Bipolar Transistors (HBTs in the AlGaAs/GaAs materials systems. Because of the complex nature and multi-faceted operation modes of these devices, reliability studies must go beyond the typical Arrhenius accelerated life tests. We review the electric field driven degradation in devices with different gate metallization, device dimensions, electric field mitigation techniques (such as source field plate, and the effect of device fabrication processes for both DC and RF stress conditions. We summarize the degradation mechanisms that limit the lifetime of these devices. A variety of contact and surface degradation mechanisms have been reported, but differ in the two device technologies: For HEMTs, the layers are thin and relatively lightly doped compared to HBT structures and there is a metal Schottky gate that is directly on the semiconductor. By contrast, the HBT relies on pn junctions for current modulation and has only Ohmic contacts. This leads to different degradation mechanisms for the two types of devices.

  16. Degradation Mechanisms for GaN and GaAs High Speed Transistors

    Science.gov (United States)

    Cheney, David J.; Douglas, Erica A.; Liu, Lu; Lo, Chien-Fong; Gila, Brent P.; Ren, Fan; Pearton, Stephen J.

    2012-01-01

    We present a review of reliability issues in AlGaN/GaN and AlGaAs/GaAs high electron mobility transistors (HEMTs) as well as Heterojunction Bipolar Transistors (HBTs) in the AlGaAs/GaAs materials systems. Because of the complex nature and multi-faceted operation modes of these devices, reliability studies must go beyond the typical Arrhenius accelerated life tests. We review the electric field driven degradation in devices with different gate metallization, device dimensions, electric field mitigation techniques (such as source field plate), and the effect of device fabrication processes for both DC and RF stress conditions. We summarize the degradation mechanisms that limit the lifetime of these devices. A variety of contact and surface degradation mechanisms have been reported, but differ in the two device technologies: For HEMTs, the layers are thin and relatively lightly doped compared to HBT structures and there is a metal Schottky gate that is directly on the semiconductor. By contrast, the HBT relies on pn junctions for current modulation and has only Ohmic contacts. This leads to different degradation mechanisms for the two types of devices.

  17. Radiation effect of doping and bias conditions on NPN bipolar junction transistors

    International Nuclear Information System (INIS)

    Xi Shanbin; Wang Yiyuan; Xu Fayue; Zhou Dong; Li Ming; Wang Fei; Wang Zhikuan; Yang Yonghui; Lu Wu

    2011-01-01

    In this paper,we investigate 60 Co γ-ray irradiation effects and annealing behaviors of NPN bipolar junction transistors of the same manufacturing technology but different doping concentrations. The transistors of different doping concentrations differ in responses of the radiation effect. More degradation was observed with the transistors of low concentration-doped NPN transistors than the high concentration-doped NPN transistors. The results also demonstrate that reverse-biased transistors are more sensitive to radiation than the forward-biased ones. Mechanisms of the radiation responses are analyzed. (authors)

  18. A photocurrent compensation method of bipolar transistors under high dose rate radiation and its experimental research

    International Nuclear Information System (INIS)

    Yin Xuesong; Liu Zhongli; Li Chunji; Yu Fang

    2005-01-01

    Experiment using discrete bipolar transistors has been performed to verify the effect of the photocurrent compensation method. The theory of the dose rate effects of bipolar transistors and the photocurrent compensation method are introduced. The comparison between the response of hardened and unhardened circuits under high dose rate radiation is discussed. The experimental results show instructiveness to the hardness of bipolar integrated circuits under transient radiation. (authors)

  19. Validation of Nonlinear Bipolar Transistor Model by Small-Signal Measurements

    DEFF Research Database (Denmark)

    Vidkjær, Jens; Porra, V.; Zhu, J.

    1992-01-01

    A new method for the validity analysis of nonlinear transistor models is presented based on DC-and small-signal S-parameter measurements and realistic consideration of the measurement and de-embedding errors and singularities of the small-signal equivalent circuit. As an example, some analysis...... results for an extended Gummel Poon model are presented in the case of a UHF bipolar power transistor....

  20. Radiation effects on JFETS, MOSFETS, and bipolar transistors, as related to SSC circuit design

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, E J; Gray, B; Wu, A [Dept. of Electrical and Computer Engineering, Univ. of Tennessee, Knoxville, TN (United States); Alley, G T; Britton, Jr, C L [Oak Ridge National Lab., TN (United States); Skubic, P L [Univ. of Oklahoma, Dept. of Physics and Astronomy, Norman, OK (United States)

    1991-10-01

    Some results of radiation effects on selected junction field-effect transistors, MOS field-effect transistors, and bipolar junction transistors are presented. The evaluations include dc parameters, as well as capacitive variations and noise evaluations. The tests are made at the low current and voltage levels (in particular at currents {<=} 1 mA) that are essential for the low-power regimes required by SSC circuitry. Detailed noise data are presented both before and after 5-Mrad (gamma) total-dose exposure. SPICE radiation models for three high-frequency bipolar processes are compared for a typical charge-sensitive preamplifier. (orig.).

  1. Atomic-Monolayer Two-Dimensional Lateral Quasi-Heterojunction Bipolar Transistors with Resonant Tunneling Phenomenon

    KAUST Repository

    Lin, Che-Yu

    2017-10-04

    High-frequency operation with ultra-thin, lightweight and extremely flexible semiconducting electronics are highly desirable for the development of mobile devices, wearable electronic systems and defense technologies. In this work, the first experimental observation of quasi-heterojunction bipolar transistors utilizing a monolayer of the lateral WSe2-MoS2 junctions as the conducting p-n channel is demonstrated. Both lateral n-p-n and p-n-p heterojunction bipolar transistors are fabricated to exhibit the output characteristics and current gain. A maximum common-emitter current gain of around 3 is obtained in our prototype two-dimensional quasi-heterojunction bipolar transistors. Interestingly, we also observe the negative differential resistance in the electrical characteristics. A potential mechanism is that the negative differential resistance is induced by resonant tunneling phenomenon due to the formation of quantum well under applying high bias voltages. Our results open the door to two-dimensional materials for high-frequency, high-speed, high-density and flexible electronics.

  2. Atomic-Monolayer Two-Dimensional Lateral Quasi-Heterojunction Bipolar Transistors with Resonant Tunneling Phenomenon

    KAUST Repository

    Lin, Che-Yu; Zhu, Xiaodan; Tsai, Shin-Hung; Tsai, Shiao-Po; Lei, Sidong; Li, Ming-Yang; Shi, Yumeng; Li, Lain-Jong; Huang, Shyh-Jer; Wu, Wen-Fa; Yeh, Wen-Kuan; Su, Yan-Kuin; Wang, Kang L.; Lan, Yann-Wen

    2017-01-01

    High-frequency operation with ultra-thin, lightweight and extremely flexible semiconducting electronics are highly desirable for the development of mobile devices, wearable electronic systems and defense technologies. In this work, the first experimental observation of quasi-heterojunction bipolar transistors utilizing a monolayer of the lateral WSe2-MoS2 junctions as the conducting p-n channel is demonstrated. Both lateral n-p-n and p-n-p heterojunction bipolar transistors are fabricated to exhibit the output characteristics and current gain. A maximum common-emitter current gain of around 3 is obtained in our prototype two-dimensional quasi-heterojunction bipolar transistors. Interestingly, we also observe the negative differential resistance in the electrical characteristics. A potential mechanism is that the negative differential resistance is induced by resonant tunneling phenomenon due to the formation of quantum well under applying high bias voltages. Our results open the door to two-dimensional materials for high-frequency, high-speed, high-density and flexible electronics.

  3. Atomic-Monolayer Two-Dimensional Lateral Quasi-Heterojunction Bipolar Transistors with Resonant Tunneling Phenomenon.

    Science.gov (United States)

    Lin, Che-Yu; Zhu, Xiaodan; Tsai, Shin-Hung; Tsai, Shiao-Po; Lei, Sidong; Shi, Yumeng; Li, Lain-Jong; Huang, Shyh-Jer; Wu, Wen-Fa; Yeh, Wen-Kuan; Su, Yan-Kuin; Wang, Kang L; Lan, Yann-Wen

    2017-11-28

    High-frequency operation with ultrathin, lightweight, and extremely flexible semiconducting electronics is highly desirable for the development of mobile devices, wearable electronic systems, and defense technologies. In this work, the experimental observation of quasi-heterojunction bipolar transistors utilizing a monolayer of the lateral WSe 2 -MoS 2 junctions as the conducting p-n channel is demonstrated. Both lateral n-p-n and p-n-p heterojunction bipolar transistors are fabricated to exhibit the output characteristics and current gain. A maximum common-emitter current gain of around 3 is obtained in our prototype two-dimensional quasi-heterojunction bipolar transistors. Interestingly, we also observe the negative differential resistance in the electrical characteristics. A potential mechanism is that the negative differential resistance is induced by resonant tunneling phenomenon due to the formation of quantum well under applying high bias voltages. Our results open the door to two-dimensional materials for high-frequency, high-speed, high-density, and flexible electronics.

  4. DEVELOPMENT OF CONTROLLED RECTIFIERS BASED ON THE BIPOLAR WITH STATIC INDUCTION TRANSISTORS (BSIT

    Directory of Open Access Journals (Sweden)

    F. I. Bukashev

    2016-01-01

    Full Text Available Aim. The aim of this study is to develop one of the most perspective semiconductor device suitable for creation and improvement of controlled rectifiers, bipolar static induction transistor.Methods. Considered are the structural and schematic circuit controlled rectifier based on bipolar static induction transistor (BSIT, and the criterion of effectiveness controlled rectifiers - equivalent to the voltage drop.Results. Presented are the study results of controlled rectifier layout on BSIT KT698I. It sets the layout operation at an input voltage of 2.0 V at a frequency up to 750 kHz. The efficiency of the studied layouts at moderate current densities as high as 90 % .Offered is optimization of technological route microelectronic controlled rectifier manufacturing including BSIT and integrated bipolar elements of the scheme management.Conclusion. It is proved that the most efficient use of the bipolar static induction transistor occurs at the low voltage controlled rectifiers 350-400 kHz, at frequencies in conjunction with a low-voltage control circuit.It is proved that the increase of the functional characteristics of the converters is connected to the expansion of the input voltage and output current ranges

  5. Bipolar Transistors Can Detect Charge in Electrostatic Experiments

    Science.gov (United States)

    Dvorak, L.

    2012-01-01

    A simple charge indicator with bipolar transistors is described that can be used in various electrostatic experiments. Its behaviour enables us to elucidate links between 'static electricity' and electric currents. In addition it allows us to relate the sign of static charges to the sign of the terminals of an ordinary battery. (Contains 7 figures…

  6. Experiments with Charge Indicator Based on Bipolar Transistors

    Science.gov (United States)

    Dvorak, Leos; Planinsic, Gorazd

    2012-01-01

    A simple charge indicator with bipolar transistors described recently enables us to perform a number of experiments suitable for high-school physics. Several such experiments are presented and discussed in this paper as well as some features of the indicator important for its use in schools, namely its sensitivity and robustness, i.e. the…

  7. Lateral n-p-n bipolar transistors by ion implantation into semi-insulating GaAs

    International Nuclear Information System (INIS)

    Canfield, P.; Forbes, L.

    1988-01-01

    GaAs bipolar transistors have not seen the major development effort that GaAs MESFETs have due primarily to the short minority carrier lifetimes in GaAs. The short minority carrier lifetimes require that the base region be very thin which, if done by implantation, requires that the doping be high to obtain a well defined base profile. These requirements are very difficult to achieve in GaAs and typically, if high current gain and high speed are desired for a bipolar technology, then heterostructure bipolars are the appropriate technology, although the cost of heterostructure devices will be prohibitive for some time to come. For applications requiring low current gain, more modest fabrication rules can be followed. Lateral bipolars are particularly attractive since they would be easier to fabricate than a planar bipolar or a heterojunction bipolar. Lateral bipolars do not require steps or deep contacts to make contact with the subcollector or highly doped very thin epilayers for the base region and they can draw upon the semi-insulating properties of the GaAs substrates for device isolation. Bipolar transistors are described and shown to work successfully. (author)

  8. Ionizing/displacement synergistic effects induced by gamma and neutron irradiation in gate-controlled lateral PNP bipolar transistors

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chenhui, E-mail: wangchenhui@nint.ac.cn [State Key Laboratory of Intense Pulsed Irradiation Simulation and Effect, Northwest Institute of Nuclear Technology, P.O. Box 69-10, Xi’an 710024 (China); Chen, Wei; Yao, Zhibin; Jin, Xiaoming; Liu, Yan; Yang, Shanchao [State Key Laboratory of Intense Pulsed Irradiation Simulation and Effect, Northwest Institute of Nuclear Technology, P.O. Box 69-10, Xi’an 710024 (China); Wang, Zhikuan [State Key Laboratory of Analog Integrated Circuit, Chongqing 400060 (China)

    2016-09-21

    A kind of gate-controlled lateral PNP bipolar transistor has been specially designed to do experimental validations and studies on the ionizing/displacement synergistic effects in the lateral PNP bipolar transistor. The individual and mixed irradiation experiments of gamma rays and neutrons are accomplished on the transistors. The common emitter current gain, gate sweep characteristics and sub-threshold sweep characteristics are measured after each exposure. The results indicate that under the sequential irradiation of gamma rays and neutrons, the response of the gate-controlled lateral PNP bipolar transistor does exhibit ionizing/displacement synergistic effects and base current degradation is more severe than the simple artificial sum of those under the individual gamma and neutron irradiation. Enough attention should be paid to this phenomenon in radiation damage evaluation. - Highlights: • A kind of gate-controlled lateral PNP bipolar transistor has been specially designed to facilitate the analysis of ionizing/displacement synergistic effects induced by the mixed irradiation of gamma and neutron. • The difference between ionizing/displacement synergistic effects and the simple sum of TID and displacement effects is analyzed. • The physical mechanisms of synergistic effects are explained.

  9. Total dose effects on elementary transistors of a comparator in bipolar technology

    International Nuclear Information System (INIS)

    Sarrabayrouse, G.; Guerre, F.X.

    1995-01-01

    In the present work we investigate elementary transistors behaviour of an Integrated Circuit using junction isolation bipolar technology. Polarization conditions and dose rate effects on the main elementary transistor types are analysed. Furthermore, the IC electronic function degradations are studied. Finally, a comparison between the function degradations and the elementary component ones is attempted. (author)

  10. An ultra-high-speed direct digital frequency synthesizer implemented in GaAs HBT technology

    International Nuclear Information System (INIS)

    Chen Gaopeng; Wu Danyu; Jin Zhi; Liu Xinyu

    2010-01-01

    This paper presents a 10-GHz 8-bit direct digital synthesizer (DDS) microwave monolithic integrated circuit implemented in 1 μm GaAs HBT technology. The DDS takes a double-edge-trigger (DET) 8-stage pipeline accumulator with sine-weighted DAC-based ROM-less architecture, which can maximize the utilization ratio of the GaAs HBT's high-speed potential. With an output frequency up to 5 GHz, the DDS gives an average spurious free dynamic range of 23.24 dBc through the first Nyquist band, and consumes 2.4 W of DC power from a single -4.6 V DC supply. Using 1651 GaAs HBT transistors, the total area of the DDS chip is 2.4 x 2.0 mm 2 . (semiconductor integrated circuits)

  11. Electrical characterization of commercial NPN bipolar junction transistors under neutron and gamma irradiation

    Directory of Open Access Journals (Sweden)

    OO Myo Min

    2014-01-01

    Full Text Available Electronics components such as bipolar junction transistors, diodes, etc. which are used in deep space mission are required to be tolerant to extensive exposure to energetic neutrons and ionizing radiation. This paper examines neutron radiation with pneumatic transfer system of TRIGA Mark-II reactor at the Malaysian Nuclear Agency. The effects of the gamma radiation from Co-60 on silicon NPN bipolar junction transistors is also be examined. Analyses on irradiated transistors were performed in terms of the electrical characteristics such as current gain, collector current and base current. Experimental results showed that the current gain on the devices degraded significantly after neutron and gamma radiations. Neutron radiation can cause displacement damage in the bulk layer of the transistor structure and gamma radiation can induce ionizing damage in the oxide layer of emitter-base depletion layer. The current gain degradation is believed to be governed by the increasing recombination current in the base-emitter depletion region.

  12. Low-frequency noise behavior of polysilicon emitter bipolar junction transistors: a review

    Science.gov (United States)

    Deen, M. Jamal; Pascal, Fabien

    2003-05-01

    For many analog integrated circuit applications, the polysilicon emitter bipolar junction transistor (PE-BJT) is still the preferred choice because of its higher operational frequency and lower noise performance characteristics compared to MOS transistors of similar active areas and at similar biasing currents. In this paper, we begin by motivating the reader with reasons why bipolar transistors are still of great interest for analog integrated circuits. This motivation includes a comparison between BJT and the MOSFET using a simple small-signal equivalent circuit to derive important parameters that can be used to compare these two technologies. An extensive review of the popular theories used to explain low frequency noise results is presented. However, in almost all instances, these theories have not been fully tested. The effects of different processing technologies and conditions on the noise performance of PE-BJTs is reviewed and a summary of some of the key technological steps and device parameters and their effects on noise is discussed. The effects of temperature and emitter geometries scaling is reviewed. It is shown that dispersion of the low frequency noise in ultra-small geometries is a serious issue since the rate of increase of the noise dispersion is faster than the noise itself as the emitter geometry is scaled to smaller values. Finally, some ideas for future research on PE-BJTs, some of which are also applicable to SiGe heteorjunction bipolar transistors and MOSFETs, are presented after the conclusions.

  13. Evaluation of temperature-enhanced gain degradation of verticle npn and lateral pnp bipolar transistors

    International Nuclear Information System (INIS)

    Witczak, S.C.; Lacoe, R.C.; Galloway, K.F.

    1997-01-01

    The effect of dose rate on radiation-induced gain degradation is compared for verticle npn and lateral pnp bipolar transistors. High dose rate irradiations at elevated temperatures are more effective at simulating low dose rate degradation in the lateral pnp transistors

  14. Electrical characteristics of SiGe-base bipolar transistors on thin-film SOI substrates

    International Nuclear Information System (INIS)

    Liao, Shu-Hui; Chang, Shu-Tong

    2010-01-01

    This paper, based on two-dimensional simulations, provides a comprehensive analysis of the electrical characteristics of the Silicon germanium (SiGe)-base bipolar transistors on thin-film siliconon-insulator (SOI) substrates. The impact of the buried oxide thickness (T OX ), the emitter width (W E ), and the lateral distance between the edge of the intrinsic base and the reach-through region (L col ) on both the AC and DC device characteristics was analyzed in detail. Regarding the DC characteristics, the simulation results suggest that a thicker T OX gives a larger base-collector breakdown voltage (BV CEO ), whereas reducing the T OX leads to an enhanced maximum electric field at the B-C junction. As for the AC characteristics, cut-off frequency (f T ) increases slightly with increasing buried oxide thickness and finally saturates to a constant value when the buried oxide thickness is about 0.15 μm. The collector-substrate capacitance (C CS ) decreases with increasing buried oxide thickness while the maximum oscillation frequency (f max ) increases with increasing buried oxide thickness. Furthermore, the impact of self-heating effects in the device was analyzed in various areas. The thermal resistance as a function of the buried oxide thickness indicates that the thermal resistance of the SiGe-base bipolar transistor on a SOI substrate is slightly higher than that of a bulk SiGe-base bipolar transistor. The thermal resistance is reduced by ∼37.89% when the emitter width is increased by a factor of 5 for a fixed buried oxide thickness of 0.1 μm. All the results can be used to design and optimize SiGe-base bipolar transistors on SOI substrates with minimum thermal resistance to enhance device performance.

  15. Controlled ion-beam transformation of silicon bipolar microwave power transistor's characteristics

    International Nuclear Information System (INIS)

    Solodukha, V.A.; Snitovskij, Yu.P.

    2015-01-01

    In this article, a method for changing the silicon bipolar microwave power transistor's characteristics in a direct and deliberate manner by modifying the chemical composition at the molybdenum - silicon boundary, the electro-physical properties of molybdenum - silicon contacts, and the electrophysical characteristics of transistor structure areas by the phosphorus ions irradiation of generated ohmic molybdenum - silicon contacts to the transistor emitters is proposed for the first time. The possibilities of this method are investigated and confirmed experimentally. (authors)

  16. An improved bipolar junction transistor model for electrical and radiation effects

    International Nuclear Information System (INIS)

    Kleiner, C.T.; Messenger, G.C.

    1982-01-01

    The use of bipolar technology in hardened electronic design requires an in-depth understanding of how the Bipolar Junction Transistor (BJT) behaves under normal electrical and radiation environments. Significant improvements in BJT process technology have been reported, and the successful use of sophisticated Computer Aided Design (CAD) tools has aided implementation with respect to specific families of hardened devices. The most advanced BJT model used to date is the Improved Gummel-Poon (IGP) model which is used in CAA programs such as the SPICE II and SLICE programs. The earlier Ebers-Moll model (ref 1 and 2) has also been updated to compare with the older Gummel-Poon model. This paper describes an adaptation of an existing computer model which incorporates the best features of both models into a new, more accurate model called the Improved Bipolar Junction Transistor model. This paper also describes a unique approach to data reduction for the B(I /SUB c/) and V /SUB BE/(ACT) vs I /SUB c/characterizations which has been successfully programmed in Basic using a Commodore PET computer. This model is described in the following sections

  17. Thermal stability improvement of a multiple finger power SiGe heterojunction bipolar transistor under different power dissipations using non-uniform finger spacing

    International Nuclear Information System (INIS)

    Chen Liang; Zhang Wan-Rong; Jin Dong-Yue; Shen Pei; Xie Hong-Yun; Ding Chun-Bao; Xiao Ying; Sun Bo-Tao; Wang Ren-Qing

    2011-01-01

    A method of non-uniform finger spacing is proposed to enhance thermal stability of a multiple finger power SiGe heterojunction bipolar transistor under different power dissipations. Temperature distribution on the emitter fingers of a multi-finger SiGe heterojunction bipolar transistor is studied using a numerical electro-thermal model. The results show that the SiGe heterojunction bipolar transistor with non-uniform finger spacing has a small temperature difference between fingers compared with a traditional uniform finger spacing heterojunction bipolar transistor at the same power dissipation. What is most important is that the ability to improve temperature non-uniformity is not weakened as power dissipation increases. So the method of non-uniform finger spacing is very effective in enhancing the thermal stability and the power handing capability of power device. Experimental results verify our conclusions. (interdisciplinary physics and related areas of science and technology)

  18. Silicon-Germanium Front-End Electronics for Space-Based Radar Applications

    Data.gov (United States)

    National Aeronautics and Space Administration — Over the past two decades, Silicon-Germanium (SiGe) heterojunction bipolar transistor (HBT) technology has emerged as a strong platform for high-frequency...

  19. An investigation of group IV alloys and their applications in bipolar transistors

    International Nuclear Information System (INIS)

    Anteney, I.M.

    2000-09-01

    This thesis investigates the use of carbon in group IV alloys and their potential uses in bipolar transistors. The first part of the thesis investigates the ability of carbon to suppress transient enhanced diffusion in SiGe heterojunction bipolar transistors, whilst the second part deals with the impact of carbon incorporation on the electrical properties of polycrystalline silicon and silicon-germanium films. A background doping concentration (10 20 cm -3 ) of C has been introduced into the base of SiGe HBTs with the aim of studying the effects of C on TED of B from the base. An electrical method is used to extract the bandgap narrowing in the base of SiGe and SiGe:C HBTs through measurements of the temperature dependence of I c at different C/B reverse biases. The method is very sensitive to small amounts of dopant out-diffusion from the base and hence is ideal for determining the effect of C on TED. Extracted BGN values of 115meV and 173meV were obtained for the SiGe and SiGe:C HBTs respectively, for a C/B reverse bias of 0V. Increasing the C/B reverse bias to 1V increased the extracted BGN of the SiGe HBT to 145meV, but left the SiGe:C value unchanged. This demonstrates that no parasitic energy barrier exists in the SiGe:C HBT and that TED has been suppressed. The effect of carbon position and concentration has been studied by introducing a peak C concentration of 10 20 cm -3 in the collector and 1.1x10 19 cm -3 or 1.5x10 19 cm -3 C in the base. From these measurements it has been shown that TED is only suppressed in the device with 1.5x10 19 cm -3 C in the base, indicating that a C concentration of 1.5x10 19 cm -3 is needed to suppress TED and that the C needs to be co-located with the B profile. The effects of carbon on the electrical properties of polycrystalline Si and SiGe films have been investigated. The resistivity, Hall mobility (μ H ) and effective carrier concentration (N EFF ) of n- and p-type polySi 1-y C y and polySi 0.82-y Ge 0.18 C y layers

  20. Dose Rate Effects in Linear Bipolar Transistors

    Science.gov (United States)

    Johnston, Allan; Swimm, Randall; Harris, R. D.; Thorbourn, Dennis

    2011-01-01

    Dose rate effects are examined in linear bipolar transistors at high and low dose rates. At high dose rates, approximately 50% of the damage anneals at room temperature, even though these devices exhibit enhanced damage at low dose rate. The unexpected recovery of a significant fraction of the damage after tests at high dose rate requires changes in existing test standards. Tests at low temperature with a one-second radiation pulse width show that damage continues to increase for more than 3000 seconds afterward, consistent with predictions of the CTRW model for oxides with a thickness of 700 nm.

  1. A study of process-related electrical defects in SOI lateral bipolar transistors fabricated by ion implantation

    Science.gov (United States)

    Yau, J.-B.; Cai, J.; Hashemi, P.; Balakrishnan, K.; D'Emic, C.; Ning, T. H.

    2018-04-01

    We report a systematic study of process-related electrical defects in symmetric lateral NPN transistors on silicon-on-insulator (SOI) fabricated using ion implantation for all the doped regions. A primary objective of this study is to see if pipe defects (emitter-collector shorts caused by locally enhanced dopant diffusion) are a show stopper for such bipolar technology. Measurements of IC-VCE and Gummel currents in parallel-connected transistor chains as a function of post-fabrication rapid thermal anneal cycles allow several process-related electrical defects to be identified. They include defective emitter-base and collector-base diodes, pipe defects, and defects associated with a dopant-deficient region in an extrinsic base adjacent its intrinsic base. There is no evidence of pipe defects being a major concern in SOI lateral bipolar transistors.

  2. Simulation of Heating of an Oil-Cooled Insulated Gate Bipolar Transistors Converter Model

    National Research Council Canada - National Science Library

    Ovrebo, Gregory

    2004-01-01

    I used SolidWorks a three-dimensional modeling software, and FloWorks, a fluid dynamics analysis tool, to simulate oil flow and heat transfer in a heat sink structure attached to three insulated gate bipolar transistors...

  3. Single-event burnout of power bipolar junction transistors

    International Nuclear Information System (INIS)

    Titus, J.L.; Johnson, G.H.; Schrimpf, R.D.; Galloway, K.F.

    1991-01-01

    Experimental evidence of single-event burnout of power bipolar junctions transistors (BJTs) is reported for the first time. Several commercial power BJTs were characterized in a simulated cosmic ray environment using mono-energetic ions at the tandem Van de Graaff accelerator facility at Brookhaven National Laboratory. Most of the device types exposed to this simulated environment exhibited burnout behavior. In this paper the experimental technique, data, and results are presented, while a qualitative model is used to help explain those results and trends observed in this experiment

  4. Neutron Radiation Effect On 2N2222 And NTE 123 NPN Silicon Bipolar Junction Transistors

    International Nuclear Information System (INIS)

    Oo, Myo Min; Rashid, N K A Md; Hasbullah, N F; Karim, J Abdul; Zin, M R Mohamed

    2013-01-01

    This paper examines neutron radiation with PTS (Pneumatic Transfer System) effect on silicon NPN bipolar junction transistors (2N2222 and NTE 123) and analysis of the transistors in terms of electrical characterization such as current gain after neutron radiation. The key parameters are measured with Keithley 4200SCS. Experiment results show that the current gain degradation of the transistors is very sensitive to neutron radiation. The neutron radiation can cause displacement damage in the bulk layer of the transistor structure. The current degradation is believed to be governed by increasing recombination current between the base and emitter depletion region

  5. A study of s new power semiconductor insulated gate bipolar transistor (IGBT) characteristics and its application to automotive ignition

    International Nuclear Information System (INIS)

    Rabah, K.V.O.

    1995-05-01

    Assessment has been made of the problem of the on-resistance and temperature effects in the three power transistor combinations, such as Darlington-types or IGBT. The IGBT is a device in which the drain of the MOSFET feeds the bipolar base in monolithic (IC and Power on the same chip) to give it both the MOS and bipolar advantages. The high temperature operating characteristics of the device are discussed and compared to that of power bipolar transistor. Unlike the power bipolar transistor whose operating current density shows current crowding at above forward collector current of 4Amps and forward voltage drop above 0.4V, the IGBT is found to maintain its high current density above forward collector of current 1Amp (or a forward voltage drop above 1.2V). The results also indicate that these devices (IGBTs) can be interdigited (paralleled) without current hogging problems if the forward conduction occurs at forward voltage drops in excess of 1.2V, and this makes it the best candidate for automotive ignition power switches. (author). 20 refs, 10 figs, 1 tab

  6. The Bipolar Field-Effect Transistor: XIII. Physical Realizations of the Transistor and Circuits (One-Two-MOS-Gates on Thin-Thick Pure-Impure Base)

    International Nuclear Information System (INIS)

    Sah, C.-T.; Jie Binbin

    2009-01-01

    This paper reports the physical realization of the Bipolar Field-Effect Transistor (BiFET) and its one-transistor basic building block circuits. Examples are given for the one and two MOS gates on thin and thick, pure and impure base, with electron and hole contacts, and the corresponding theoretical current-voltage characteristics previously computed by us, without generation-recombination-trapping-tunneling of electrons and holes. These examples include the one-MOS-gate on semi-infinite thick impure base transistor (the bulk transistor) and the impurethin-base Silicon-on-Insulator (SOI) transistor and the two-MOS-gates on thin base transistors (the FinFET and the Thin Film Transistor TFT). Figures are given with the cross-section views containing the electron and hole concentration and current density distributions and trajectories and the corresponding DC current-voltage characteristics.

  7. Study of an Insulated Gate Bipolar Transistor (IGBT) and its connection in series. Application at a chopper 1500V-5A-10kHz

    International Nuclear Information System (INIS)

    Gros, P.

    1993-01-01

    In the frame of the tokamak ITER (International Thermonuclear Experimental Reactor) we have studied, for neutral particle injection, a converter with at least two static interrupters by Mosfet transistor, bipolar transistor or Insulated Gate Bipolar Transistor (IGBT). After a comparison between these three types of transistors, by the simulating software MICROCAP, a serial of tests has shown the advantages of the IGBT. A command, associated with two IGBT of equivalent characteristics, has given a simple and efficacious solution. The performances are: (1) between two blockages: 50 ns without overvoltage, (2) between two cut-off: 60 ns. 40 figs; 30 refs; 10 annexes

  8. Improved External Base Resistance Extraction for Submicrometer InP/InGaAs DHBT Models

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Krozer, Viktor; Nodjiadjim, Virginie

    2011-01-01

    An improved direct parameter extraction method is proposed for III–V heterojunction bipolar transistor (HBT) external base resistance $R_{\\rm bx}$ extraction from forward active $S$-parameters. The method is formulated taking into account the current dependence of the intrinsic base–collector cap......An improved direct parameter extraction method is proposed for III–V heterojunction bipolar transistor (HBT) external base resistance $R_{\\rm bx}$ extraction from forward active $S$-parameters. The method is formulated taking into account the current dependence of the intrinsic base...... factor given as the ratio of the emitter to the collector area. The determination of the parameters $I_{p}$ and $X_{0}$ from experimental $S$-parameters is described. The method is applied to high-speed submicrometer InP/InGaAs DHBT devices and leads to small-signal equivalent circuit models, which...

  9. Analysis of the Nonlinear Characteristics of Microwave Power Heterojunction Bipolar Transistors and Optoelectronic Integrated Circuits.

    Science.gov (United States)

    Samelis, Apostolos

    A physical basis for large-signal HBT modeling was established in terms of transit times using a Monte Carlo analysis of AlGaAs/GaAs and GaInP/GaAs designs. Static carriers located in the collector-subcollector interface were found to prohibit accurate evaluation of transit times from electron velocity profiles. These carriers also influence the bias dependence of device capacitances. Analytical parameter extraction techniques for DC, thermal and high frequency HBT parameters were developed and applied to HBT large-signal modeling. The "impedance block" conditioned optimization technique was introduced to facilitate parameter extraction. Physical analysis of HBTs by means of Volterra Series techniques showed that C_{bc } dominates nonlinear distortion in high gain amplifiers. Designs with that C_{bc }-V_{cb} characteristics i.e. p -n collector HBTs lead to more than 10 dB IP3 improvement over n-collector HBTs. Nonlinear current cancellation was found to improve intermodulation distortion. A Gummel -Poon-based HBT large-signal model incorporating self-heating effects was developed and applied to AlGaAs/GaAs HBTs. Maximum power drive was shown to occur using constant V _{be} father than I_ {b} bias. The device temperature of constant I_{b} biased HBTs decreases at increased rf-drive levels ensuring in this case safer device operation. A large-signal model incorporating "soft" -breakdown effects typical of InP/InGaAs HBTs was developed and found to model succesfully the power characteristics of OEICs built with them. The effective large-signal transimpedance of a cascode transimpedance preamplifier was evaluated using this model and found to degrade by 3dBOmega for a variation of P_{in} from -65 to -5 dBm. Self-bias of individual transistors was studied and found to be related to variations of the amplifier characteristics at higher rf-drive levels. The power characteristics of CE and CB AlGaAs/GaAs HBTs were investigated using an on -wafer source/load pull setup

  10. One bipolar transistor selector - One resistive random access memory device for cross bar memory array

    Science.gov (United States)

    Aluguri, R.; Kumar, D.; Simanjuntak, F. M.; Tseng, T.-Y.

    2017-09-01

    A bipolar transistor selector was connected in series with a resistive switching memory device to study its memory characteristics for its application in cross bar array memory. The metal oxide based p-n-p bipolar transistor selector indicated good selectivity of about 104 with high retention and long endurance showing its usefulness in cross bar RRAM devices. Zener tunneling is found to be the main conduction phenomena for obtaining high selectivity. 1BT-1R device demonstrated good memory characteristics with non-linearity of 2 orders, selectivity of about 2 orders and long retention characteristics of more than 105 sec. One bit-line pull-up scheme shows that a 650 kb cross bar array made with this 1BT1R devices works well with more than 10 % read margin proving its ability in future memory technology application.

  11. Effect of germanium concentrations on tunnelling current calculation of Si/Si1-xGex/Si heterojunction bipolar transistor

    Science.gov (United States)

    Hasanah, L.; Suhendi, E.; Khairrurijal

    2018-05-01

    Tunelling current calculation on Si/Si1-xGex/Si heterojunction bipolar transistor was carried out by including the coupling between transversal and longitudinal components of electron motion. The calculation results indicated that the coupling between kinetic energy in parallel and perpendicular to S1-xGex barrier surface affected tunneling current significantly when electron velocity was faster than 1x105 m/s. This analytical tunneling current model was then used to study how the germanium concentration in base to Si/Si1-xGex/Si heterojunction bipolar transistor influenced the tunneling current. It is obtained that tunneling current increased as the germanium concentration given in base decreased.

  12. Photovoltaic Cells Improvised With Used Bipolar Junction Transistors

    International Nuclear Information System (INIS)

    Akintayo, J. A

    2002-01-01

    The understanding of the underlying principle that the solar cell consists of a p-n junction is exploited to adapt the basic NPN or PNP Bipolar Junction Transistors (BJT) to serve as solar cells. In this mode the in improvised solar cell have employed just the emitter and the base sections with an intact emitter/base junction as the active PN area. The improvised devices tested screened and sorted are wired up in strings, blocks and modules. The photovoltaic modules realised tested as close replica of solar cells with output voltage following insolation level. Further work need be done on the modules to make them generate usable levels of output voltage and current

  13. De-embedding and Modelling of pnp SiGe HBTs

    DEFF Research Database (Denmark)

    Hadziabdic, Dzenan; Jiang, Chenhui; Johansen, Tom Keinicke

    2007-01-01

    In this work we present a direct parameter extraction procedure for SiGe pnp heterojunction bipolar transistor (HBT) large-signal and small-signal models. Test structure parasitics are removed from the measured small-signal parameters using an open-short de-embedding technique, improved to accoun...

  14. A novel technique for CAD-optimization of analog circuits with bipolar transistors

    Directory of Open Access Journals (Sweden)

    B. Dimov

    2009-05-01

    Full Text Available In this paper, a novel approach for robust automatic optimization of analog circuits with bipolar transistors is presented. It includes additional formal parameters into the device model cards, which sweep the model parameters smoothly between the different device types. In this way, not only the sizing, but also the choice of the device type is committed to the optimization tool, thus improving the efficiency of the design process significantly.

  15. MHD simulation of Columbia HBT

    International Nuclear Information System (INIS)

    Li, X.L.

    1987-01-01

    The plasma of Columbia High Beta Tokamak (HBT) is studied numerically by using the two dimensional resistive MHD model. The main object of this work is to understand the high beta formation process of HBT plasma and to compare the simulation with the experiments. 21 refs., 48 figs., 2 tabs

  16. An analog front-end bipolar-transistor integrated circuit for the SDC silicon tracker

    International Nuclear Information System (INIS)

    Kipnis, I.; Spieler, H.; Collins, T.

    1994-01-01

    Since 1989 the Solenoidal Detector Collaboration (SDC) has been developing a general purpose detector to be operated at the Superconducting Super Collider (SSC). A low-noise, low-power, high-bandwidth, radiation hard, silicon bipolar-transistor full-custom integrated circuit (IC) containing 64 channels of analog signal processing has been developed for the SDS silicon tracker. The IC was designed and tested at LBL and was fabricated using AT and T's CBIC-U2, 4 GHz f T complementary bipolar technology. Each channel contains the following functions: low-noise preamplification, pulse shaping and threshold discrimination. This is the first iteration of the production analog IC for the SDC silicon tracker. The IC is laid out to directly match the 50 μm pitch double-sided silicon strip detector. The chip measures 6.8 mm x 3.1 mm and contains 3,600 transistors. Three stages of amplification provide 180 mV/fC of gain with a 35 nsec peaking time at the comparator input. For a 14 pF detector capacitance, the equivalent noise charge is 1300 el. rms at a power consumption of 1 mW/channel from a single 3.5 V supply. With the discriminator threshold set to 4 times the noise level, a 16nsec time-walk for 1.25 to 10 fC signals is achieved using a time-walk compensation network. Irradiation tests at TRIUMF to a φ = 10 14 protons/cm 2 have been performed on the JC, demonstrating the radiation hardness of the complementary bipolar process

  17. The free electron gas primary thermometer using an ordinary bipolar junction transistor approaches ppm accuracy

    Science.gov (United States)

    Mimila-Arroyo, J.

    2017-06-01

    In this paper, it is demonstrated that the free electron gas primary thermometer based on a bipolar junction transistor is able to provide the temperature with an accuracy of a few parts per million. Its simple functioning principle exploits the behavior of the collector current when properly biased to extract the temperature. Using general purpose silicon transistors at the water triple point (273.16 K) and gallium melting point (302.9146), an accuracy of a few parts per million has been reached, constituting the simplest and the easiest to operate primary thermometer, that might be considered even for the redefinition of Kelvin.

  18. Combined effects of 60Co dose and high frequency interferences on a discrete bipolar transistor

    International Nuclear Information System (INIS)

    Doridant, A.; Raoult, J.; Jarrix, S.; Blain, A.; Dusseau, L.; Hoffmann, P.; Chatry, N.; Calvel, P.

    2012-01-01

    This paper concerns bipolar transistors subject to a double aggression: dose irradiation and high-frequency interference. The electromagnetic interference is injected in a contactless way in the near-field zone around the device. Parameters of the interference are power and frequency, the latter largely out of band of operation of the transistors. The output voltage of the transistor exhibits changes, due to rectification and to some extent to current crowding. The importance of the base bias set-up for the type of change occurring in voltage is displayed. After irradiation with a 60 Co source, the voltage output will change under electromagnetic interference but sometimes in an opposite way as initially measured. The impact of the irradiation with respect to electromagnetic susceptibility is highlighted from a physical point of view. Finally preliminary results of simulation for susceptibility prediction are given and a discussion is given on the limits of the transistor model used. (authors)

  19. A 311-GHz Fundamental Oscillator Using InP HBT Technology

    Science.gov (United States)

    Gaier, Todd; Fung, King Man; Samoska, Lorene; Radisic, Vesna; Sawdai, Donald; Scott, Dennis; Deal, W.R.

    2010-01-01

    This oscillator uses a single-emitter 0.3- m InP heterojunction bipolar transistor (HBT) device with maximum frequency of oscillation (fmax) greater than 500 GHz. Due to high conductor and substrate losses at submillimeterwave frequencies, a primary challenge is to efficiently use the intrinsic device gain. This was done by using a suitable transmission-line media and circuit topology. The passive components of the oscillator are realized in a twometal process with benzocyclobutene (BCB) used as the primary transmission line dielectric. The circuit was designed using microstrip transmission lines. The oscillator is implemented in a common-base topology due to its inherent instability, and the design includes an on-chip resonator, outputmatching circuitry, and an injection-locking port, the port being used to demonstrate the injection-locking prin ciple. A free-running frequency of 311.6 GHz has been measured by down-converting the signal. Ad di tionally, injection locking has been successfully demonstrated with up to 17.8 dB of injection-locking gain. The injection-locking reference signal is generated using a 2 20 GHz frequency synthesizer, followed by a doubler, active tripler, a W-band amplifier, and then a passive tripler. Therefore, the source frequency is multiplied 18 times to obtain a signal above 300 GHz that can be used to injection lock the oscillator. Measurement shows that injection locking has improved the phase noise of the oscillator and can be also used for synchronizing a series of oscillators. A signal conductor is implemented near the BCP -InP interface and the topside of the BCB layer is fully metallized as a signal ground. Because the fields are primarily constrained in the lower permittivity BCB region, this type of transmission line is referred to as an inverted microstrip. In addition, both common-emitter and commonbase circuits were investigated to determine optimum topology for oscillator design. The common -base topology required smaller

  20. Modeling and Simulation of - and Silicon Germanium-Base Bipolar Transistors Operating at a Wide Range of Temperatures.

    Science.gov (United States)

    Shaheed, M. Reaz

    1995-01-01

    Higher speed at lower cost and at low power consumption is a driving force for today's semiconductor technology. Despite a substantial effort toward achieving this goal via alternative technologies such as III-V compounds, silicon technology still dominates mainstream electronics. Progress in silicon technology will continue for some time with continual scaling of device geometry. However, there are foreseeable limits on achievable device performance, reliability and scaling for room temperature technologies. Thus, reduced temperature operation is commonly viewed as a means for continuing the progress towards higher performance. Although silicon CMOS will be the first candidate for low temperature applications, bipolar devices will be used in a hybrid fashion, as line drivers or in limited critical path elements. Silicon -germanium-base bipolar transistors look especially attractive for low-temperature bipolar applications. At low temperatures, various new physical phenomena become important in determining device behavior. Carrier freeze-out effects which are negligible at room temperature, become of crucial importance for analyzing the low temperature device characteristics. The conventional Pearson-Bardeen model of activation energy, used for calculation of carrier freeze-out, is based on an incomplete picture of the physics that takes place and hence, leads to inaccurate results at low temperatures. Plasma -induced bandgap narrowing becomes more pronounced in device characteristics at low temperatures. Even with modern numerical simulators, this effect is not well modeled or simulated. In this dissertation, improved models for such physical phenomena are presented. For accurate simulation of carrier freeze-out, the Pearson-Bardeen model has been extended to include the temperature dependence of the activation energy. The extraction of the model is based on the rigorous, first-principle theoretical calculations available in the literature. The new model is shown

  1. Characterization of a power bipolar transistor as high-dose dosimeter for 1.9-2.2 MeV electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Fuochi, P.G., E-mail: fuochi@isof.cnr.i [ISOF-CNR Institute, Via P. Gobetti 101, I-40129, Bologna (Italy); Lavalle, M.; Corda, U. [ISOF-CNR Institute, Via P. Gobetti 101, I-40129, Bologna (Italy); Kuntz, F.; Plumeri, S. [Aerial, Parc d' Innovation Rue Laurent Fries F-67400 Illkirch (France); Gombia, E. [IMEM-CNR Institute, Viale delle Scienze 37 A, Loc. Fontanini, 43010 Parma (Italy)

    2010-04-15

    Results of the characterization studies on a power bipolar transistor investigated as a possible radiation dosimeter under laboratory condition using electron beams of energies from 2.2 to 8.6 MeV and gamma rays from a {sup 60}Co source and tested in industrial irradiation plants having high-activity {sup 60}Co gamma-source and high-energy, high-power electron beam have previously been reported. The present paper describes recent studies performed on this type of bipolar transistor irradiated with 1.9 and 2.2 MeV electron beams in the dose range 5-50 kGy. Dose response, post-irradiation heat treatment and stability, effects of temperature during irradiation in the range from -104 to +22 deg. C, dependence on temperature during reading in the range 20-50 deg. C, and the difference in response of the transistors irradiated from the plastic side and the copper side are reported. DLTS measurements performed on the irradiated devices to identify the recombination centres introduced by radiation and their dependence on dose and energy of the electron beam are also reported.

  2. Evaluation of Enhanced Low Dose Rate Sensitivity in Discrete Bipolar Junction Transistors

    Science.gov (United States)

    Chen, Dakai; Ladbury Raymond; LaBel, Kenneth; Topper, Alyson; Ladbury, Raymond; Triggs, Brian; Kazmakites, Tony

    2012-01-01

    We evaluate the low dose rate sensitivity in several families of discrete bipolar transistors across device parameter, quality assurance level, and irradiation bias configuration. The 2N2222 showed the most significant low dose rate sensitivity, with low dose rate enhancement factor of 3.91 after 100 krad(Si). The 2N2907 also showed critical degradation levels. The devices irradiated at 10 mrad(Si)/s exceeded specifications after 40 and 50 krad(Si) for the 2N2222 and 2N2907 devices, respectively.

  3. Effect of random inhomogeneities in the spatial distribution of radiation-induced defect clusters on carrier transport through the thin base of a heterojunction bipolar transistor upon neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Puzanov, A. S.; Obolenskiy, S. V., E-mail: obolensk@rf.unn.ru; Kozlov, V. A. [Lobachevsky State University of Nizhny Novgorod (NNSU) (Russian Federation)

    2016-12-15

    We analyze the electron transport through the thin base of a GaAs heterojunction bipolar transistor with regard to fluctuations in the spatial distribution of defect clusters induced by irradiation with a fissionspectrum fast neutron flux. We theoretically demonstrate that the homogeneous filling of the working region with radiation-induced defect clusters causes minimum degradation of the dc gain of the heterojunction bipolar transistor.

  4. A technique for simultaneously improving the product of cutoff frequency–breakdown voltage and thermal stability of SOI SiGe HBT

    International Nuclear Information System (INIS)

    Fu Qiang; Zhang Wan-Rong; Jin Dong-Yue; Zhao Yan-Xiao; Wang Xiao

    2016-01-01

    The product of the cutoff frequency and breakdown voltage ( f T ×BV CEO ) is an important figure of merit (FOM) to characterize overall performance of heterojunction bipolar transistor (HBT). In this paper, an approach to introducing a thin N + -buried layer into N collector region in silicon-on-insulator (SOI) SiGe HBT to simultaneously improve the FOM of f T ×BV CEO and thermal stability is presented by using two-dimensional (2D) numerical simulation through SILVACO device simulator. Firstly, in order to show some disadvantages of the introduction of SOI structure, the effects of SOI insulation layer thickness ( T BOX ) on f T , BV CEO , and the FOM of f T ×BV CEO are presented. The introduction of SOI structure remarkably reduces the electron concentration in collector region near SOI substrate insulation layer, obviously reduces f T , slightly increases BV CEO to some extent, but ultimately degrades the FOM of f T ×BV CEO . Although the f T , BV CEO , and the FOM of f T ×BV CEO can be improved by increasing SOI insulator SiO 2 layer thickness T BOX in SOI structure, the device temperature and collector current are increased due to lower thermal conductivity of SiO 2 layer, as a result, the self-heating effect of the device is enhanced, and the thermal stability of the device is degraded. Secondly, in order to alleviate the foregoing problem of low electron concentration in collector region near SOI insulation layer and the thermal stability resulting from thick T BOX , a thin N + -buried layer is introduced into collector region to not only improve the FOM of f T ×BV CEO , but also weaken the self-heating effect of the device, thus improving the thermal stability of the device. Furthermore, the effect of the location of the thin N + -buried layer in collector region is investigated in detail. The result show that the FOM of f T ×BV CEO is improved and the device temperature decreases as the N + -buried layer shifts toward SOI substrate insulation layer

  5. Anomalous dose rate effects in gamma irradiated SiGe heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Banerjee, G.; Niu, G.; Cressler, J.D.; Clark, S.D.; Palmer, M.J.; Ahlgren, D.C.

    1999-01-01

    Low dose rate (LDR) cobalt-60 (0.1 rad(Si)/s) gamma irradiated Silicon Germanium (SiGe) Heterojunction Bipolar Transistors (HBTs) were studied. Comparisons were made with devices irradiated with 300 rad(Si)/s gamma radiation to verify if LDR radiation is a serious radiation hardness assurance (RHA) issue. Almost no LDR degradation was observed in this technology up to 50 krad(Si). The assumption of the presence of two competing mechanisms is justified by experimental results. At low total dose (le20 krad), an anomalous base current decrease was observed which is attributed to self-annealing of deep-level traps to shallower levels. An increase in base current at larger total doses is attributed to radiation induced generation-recombination (G/R) center generation. Experiments on gate-assisted lateral PNP transistors and 2D numerical simulations using MEDICI were used to confirm these assertions

  6. Thermal Simulation of Switching Pulses in an Insulated Gate Bipolar Transistor (IGBT) Power Module

    Science.gov (United States)

    2015-02-01

    executed with SolidWorks Flow Simulation , a computational fluid-dynamics code. The graph in Fig. 2 shows the timing and amplitudes of power pulses...defined a convective flow of air perpendicular to the bottom surface of the mounting plate, with a velocity of 10 ft/s. The thermal simulations were...Thermal Simulation of Switching Pulses in an Insulated Gate Bipolar Transistor (IGBT) Power Module by Gregory K Ovrebo ARL-TR-7210

  7. Enhanced low dose rate radiation effect test on typical bipolar devices

    International Nuclear Information System (INIS)

    Liu Minbo; Chen Wei; Yao Zhibin; He Baoping; Huang Shaoyan; Sheng Jiangkun; Xiao Zhigang; Wang Zujun

    2014-01-01

    Two types of bipolar transistors and nine types bipolar integrated circuit were selected in the irradiation experiment at different "6"0Co γ dose rate. The base current of bipolar transistor and input bias current of amplifier and comparator was measured, low dose enhance factor of test device was obtained. The results show that bipolar device have enhanced low dose rate sensitivity, enhancement factor of bipolar integrated circuit was bigger than that of transistor, and enhanced low dose rate sensitivity greatly varied with different structure and process of bipolar device. (authors)

  8. Gamma Irradiation Performance Tests of the Bipolar Junction Transistor (BJT) for Medical Dosimetry Purposes

    International Nuclear Information System (INIS)

    Nazififard, Mohammad; Suh, Kune Y.; Faghihi, Reyhaneh; Norov, Enkhbat

    2014-01-01

    Two basic radiation damage mechanisms may affect semiconductor devices which are Displacement damage and Ionization damage. In displacement damage mechanism, the incident radiation displaces silicon atoms from their lattice sites. The resulting defects alter the electronic characteristics of the crystal. In ionization damage mechanism, the absorbed energy by electronic ionization in insulating layers liberates charge carriers, which diffuse or drift to other locations where they are trapped, leading to unintended concentrations of charge and, as a consequence, parasitic fields. Both mechanisms are important in detectors, transistors and integrated circuits. Hardly a system is immune to either one phenomenon and most are sensitive to both. This paper investigates the behavior of Bipolar Junction Transistors (BJTs), exposed to radiation in order to establish their applicability in a radiation environment

  9. Gamma Irradiation Performance Tests of the Bipolar Junction Transistor (BJT) for Medical Dosimetry Purposes

    Energy Technology Data Exchange (ETDEWEB)

    Nazififard, Mohammad; Suh, Kune Y. [PHILOSOPHIA, Inc., Seoul (Korea, Republic of); Faghihi, Reyhaneh [Kashan Univ. of Medical Science, Kashan (Iran, Islamic Republic of); Norov, Enkhbat [POSTECH, Pohang (Korea, Republic of)

    2014-05-15

    Two basic radiation damage mechanisms may affect semiconductor devices which are Displacement damage and Ionization damage. In displacement damage mechanism, the incident radiation displaces silicon atoms from their lattice sites. The resulting defects alter the electronic characteristics of the crystal. In ionization damage mechanism, the absorbed energy by electronic ionization in insulating layers liberates charge carriers, which diffuse or drift to other locations where they are trapped, leading to unintended concentrations of charge and, as a consequence, parasitic fields. Both mechanisms are important in detectors, transistors and integrated circuits. Hardly a system is immune to either one phenomenon and most are sensitive to both. This paper investigates the behavior of Bipolar Junction Transistors (BJTs), exposed to radiation in order to establish their applicability in a radiation environment.

  10. Large-signal modeling of multi-finger InP DHBT devices at millimeter-wave frequencies

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Midili, Virginio; Squartecchia, Michele

    2017-01-01

    A large-signal modeling approach has been developed for multi-finger devices fabricated in an Indium Phosphide (InP) Double Heterojunction Bipolar Transistor (DHBT) process. The approach utilizes unit-finger device models embedded in a multi-port parasitic network. The unit-finger model is based...... on an improved UCSD HBT model formulation avoiding an erroneous RciCbci transit-time contribution from the intrinsic collector region as found in other III-V based HBT models. The mutual heating between fingers is modeled by a thermal coupling network with parameters extracted from electro-thermal simulations...

  11. Total dose and dose rate models for bipolar transistors in circuit simulation.

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Phillip Montgomery; Wix, Steven D.

    2013-05-01

    The objective of this work is to develop a model for total dose effects in bipolar junction transistors for use in circuit simulation. The components of the model are an electrical model of device performance that includes the effects of trapped charge on device behavior, and a model that calculates the trapped charge densities in a specific device structure as a function of radiation dose and dose rate. Simulations based on this model are found to agree well with measurements on a number of devices for which data are available.

  12. The Complete Semiconductor Transistor and Its Incomplete Forms

    International Nuclear Information System (INIS)

    Jie Binbin; Sah, C.-T.

    2009-01-01

    This paper describes the definition of the complete transistor. For semiconductor devices, the complete transistor is always bipolar, namely, its electrical characteristics contain both electron and hole currents controlled by their spatial charge distributions. Partially complete or incomplete transistors, via coined names or/and designed physical geometries, included the 1949 Shockley p/n junction transistor (later called Bipolar Junction Transistor, BJT), the 1952 Shockley unipolar 'field-effect' transistor (FET, later called the p/n Junction Gate FET or JGFET), as well as the field-effect transistors introduced by later investigators. Similarities between the surface-channel MOS-gate FET (MOSFET) and the volume-channel BJT are illustrated. The bipolar currents, identified by us in a recent nanometer FET with 2-MOS-gates on thin and nearly pure silicon base, led us to the recognition of the physical makeup and electrical current and charge compositions of a complete transistor and its extension to other three or more terminal signal processing devices, and also the importance of the terminal contacts.

  13. Sub-bandgap photonic base current method for characterization of interface states at heterointerfaces in heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Shin, H. T.; Kim, K. H.; Kim, K. S.

    2004-01-01

    In this paper, we propose a novel photonic base current analysis method to characterize the interface states in heterojunction bipolar transistors (HBTs) by using the photonic I-V characteristics under sub-bandgap photonic excitation. For the photonic current-voltage characterization of HBTs, an optical source with a photon energy less than the bandgap energy of Al 0.3 Ga 0.7 As and GaAs (E ph = 0.95 eV g,AlGaAs = 1.79 eV, E g,GaAs = 1.45 eV) is employed for the characterization of the interface states distributed in the photo-responsive energy band (E C - 0.95 ≤ E it ≤ E C ) in emitter-base heterojunction at HBTs. The proposed novel method, which is applied to bipolar junction transistors for the first time, is simple, and an accurate analysis of interface traps in HBTs is possible. By using the photonic base-current and the dark-base-current, we qualitatively analyze the interface trap at the Al 0.3 Ga 0.7 As/GaAs heterojunction interface in HBTs.

  14. Simulation of a spintronic transistor: A study of its performance

    International Nuclear Information System (INIS)

    Pela, R.R.; Teles, L.K.

    2009-01-01

    We study theoretically the magnetic bipolar transistor, and compare its performance with common bipolar transistor. We present not only the simulation results for the characteristic curves, but also other relevant parameters related with its performance, such as: the current amplification factor, the open-loop gain, the hybrid parameters and the cutoff frequency. We noted that the spin-charge coupling introduces new phenomena that enrich the functionality characteristics of the magnetic bipolar transistor. Among other things, it has an adjustable band structure, which may be modified during the device operation; it exhibits the already known spin-voltaic effect. On the other hand, we observed that it is necessary a large g-factor to analyze the influence of the field B over the transistor. Nevertheless, we consider the magnetic bipolar transistor as a promising device for spintronic applications

  15. Space and Missile Systems Center Standard: Parts, Materials, and Processes Control Program for Space Vehicles

    Science.gov (United States)

    2013-04-12

    preparation , implementation, and operation of a Parts, Materials, and Processes (PMP) control program for use during the design, development...Processes List CDR Critical Design Review CDRL Contract Data Requirements List CMOS Complementary Metal Oxide Semiconductor CONOPS Concept of Operations...Failure Review Board GFE Government Furnished Equipment GIDEP Government Industry Data Exchange Program HBT Heterojunction Bipolar Transistor IPT

  16. Thin Time-Of-Flight PET project

    CERN Multimedia

    The pre-R&D aims at designing and producing a compact and thin Time-Of-Flight PET detector device with depth of interaction measurement capability, which employs layered silicon sensors as active material, with a readout consisting of a new generation of very-low noise and very fast electronics based on SiGe Heterojunction Bipolar Transistors (HBT) components.

  17. A Novel HBT Frequency Doubler Design for Millimeter-Wave Applications

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Krozer, Viktor; Vidkjær, Jens

    2006-01-01

    In this paper we presents a novel HBT frequency doubler design for millimeter-wave application. A HBT frequency doubler theory is described which leads to accurate design equations for optimal performance. The developed theory shows that an optimal HBT frequency doubler can be achieved using a no...

  18. ESTIMATION OF THERMAL PARAMETERS OF POWER BIPOLAR TRANSISTORS BY THE METHOD OF THERMAL RELAXATION DIFFERENTIAL SPECTROMETRY

    Directory of Open Access Journals (Sweden)

    V. S. Niss

    2015-01-01

    Full Text Available Thermal performance of electronic devices determines the stability and reliability of the equipment. This leads to the need for a detailed thermal analysis of semiconductor devices. The goal of the work is evaluation of thermal parameters of high-power bipolar transistors in plastic packages TO-252 and TO-126 by a method of thermal relaxation differential spectrometry. Thermal constants of device elements and distribution structure of thermal resistance defined as discrete and continuous spectra using previously developed relaxation impedance spectrometer. Continuous spectrum, based on higher-order derivatives of the dynamic thermal impedance, follows the model of Foster, and discrete to model of Cauer. The structure of sample thermal resistance is presented in the form of siх-chain electro-thermal RC model. Analysis of the heat flow spreading in the studied structures is carried out on the basis of the concept of thermal diffusivity. For transistor structures the area and distribution of the heat flow cross-section are determined. On the basis of the measurements the thermal parameters of high-power bipolar transistors is evaluated, in particular, the structure of their thermal resistance. For all of the measured samples is obtained that the thermal resistance of the layer planting crystal makes a defining contribution to the internal thermal resistance of transistors. In the transition layer at the border of semiconductor-solder the thermal resistance increases due to changes in the mechanism of heat transfer. Defects in this area in the form of delamination of solder, voids and cracks lead to additional growth of thermal resistance caused by the reduction of the active square of the transition layer. Method of thermal relaxation differential spectrometry allows effectively control the distribution of heat flow in high-power semiconductor devices, which is important for improving the design, improve the quality of landing crystals of power

  19. Effects of microwave pulse-width damage on a bipolar transistor

    International Nuclear Information System (INIS)

    Ma Zhen-Yang; Chai Chang-Chun; Ren Xing-Rong; Yang Yin-Tang; Chen Bin; Zhao Ying-Bo

    2012-01-01

    This paper presents a theoretical study of the pulse-width effects on the damage process of a typical bipolar transistor caused by high power microwaves (HPMs) through the injection approach. The dependences of the microwave damage power, P, and the absorbed energy, E, required to cause the device failure on the pulse width τ are obtained in the nanosecond region by utilizing the curve fitting method. A comparison of the microwave pulse damage data and the existing dc pulse damage data for the same transistor is carried out. By means of a two-dimensional simulator, ISE-TCAD, the internal damage processes of the device caused by microwave voltage signals and dc pulse voltage signals are analyzed comparatively. The simulation results suggest that the temperature-rising positions of the device induced by the microwaves in the negative and positive half periods are different, while only one hot spot exists under the injection of dc pulses. The results demonstrate that the microwave damage power threshold and the absorbed energy must exceed the dc pulse power threshold and the absorbed energy, respectively. The dc pulse damage data may be useful as a lower bound for microwave pulse damage data. (interdisciplinary physics and related areas of science and technology)

  20. A technique for simultaneously improving the product of cutoff frequency-breakdown voltage and thermal stability of SOI SiGe HBT

    Science.gov (United States)

    Fu, Qiang; Zhang, Wan-Rong; Jin, Dong-Yue; Zhao, Yan-Xiao; Wang, Xiao

    2016-12-01

    The product of the cutoff frequency and breakdown voltage (fT×BVCEO) is an important figure of merit (FOM) to characterize overall performance of heterojunction bipolar transistor (HBT). In this paper, an approach to introducing a thin N+-buried layer into N collector region in silicon-on-insulator (SOI) SiGe HBT to simultaneously improve the FOM of fT×BVCEO and thermal stability is presented by using two-dimensional (2D) numerical simulation through SILVACO device simulator. Firstly, in order to show some disadvantages of the introduction of SOI structure, the effects of SOI insulation layer thickness (TBOX) on fT, BVCEO, and the FOM of fT×BVCEO are presented. The introduction of SOI structure remarkably reduces the electron concentration in collector region near SOI substrate insulation layer, obviously reduces fT, slightly increases BVCEO to some extent, but ultimately degrades the FOM of fT×BVCEO. Although the fT, BVCEO, and the FOM of fT×BVCEO can be improved by increasing SOI insulator SiO2 layer thickness TBOX in SOI structure, the device temperature and collector current are increased due to lower thermal conductivity of SiO2 layer, as a result, the self-heating effect of the device is enhanced, and the thermal stability of the device is degraded. Secondly, in order to alleviate the foregoing problem of low electron concentration in collector region near SOI insulation layer and the thermal stability resulting from thick TBOX, a thin N+-buried layer is introduced into collector region to not only improve the FOM of fT×BVCEO, but also weaken the self-heating effect of the device, thus improving the thermal stability of the device. Furthermore, the effect of the location of the thin N+-buried layer in collector region is investigated in detail. The result show that the FOM of fT×BVCEO is improved and the device temperature decreases as the N+-buried layer shifts toward SOI substrate insulation layer. The approach to introducing a thin N+-buried layer

  1. Investigation of Impact of the Gate Circuitry on IGBT Transistor Dynamic Parameters

    Directory of Open Access Journals (Sweden)

    Vytautas Bleizgys

    2011-03-01

    Full Text Available The impact of Insulated Gate Bipolar Transistor driver circuit parameters on the rise and fall time of the collector current and voltage collector-emitter was investigated. The influence of transistor driver circuit parameters on heating of Insulated Gate Bipolar Transistors was investigated as well.Article in Lithuanian

  2. Collector modulation in high-voltage bipolar transistor in the saturation mode: Analytical approach

    Science.gov (United States)

    Dmitriev, A. P.; Gert, A. V.; Levinshtein, M. E.; Yuferev, V. S.

    2018-04-01

    A simple analytical model is developed, capable of replacing the numerical solution of a system of nonlinear partial differential equations by solving a simple algebraic equation when analyzing the collector resistance modulation of a bipolar transistor in the saturation mode. In this approach, the leakage of the base current into the emitter and the recombination of non-equilibrium carriers in the base are taken into account. The data obtained are in good agreement with the results of numerical calculations and make it possible to describe both the motion of the front of the minority carriers and the steady state distribution of minority carriers across the collector in the saturation mode.

  3. Influence of the flux density on the radiation damage of bipolar silicon transistors by protons and electrons

    International Nuclear Information System (INIS)

    Bannikov, Y.; Gorin, B.; Kozhevnikov, V.; Mikhnovich, V.; Gusev, L.

    1981-01-01

    It was found experimentally that the radiation damage of bipolar n-p-n transistors increased by a factor of 8--12 when the proton flux density was reduced from 4.07 x 10 10 to 2.5 x 10 7 cm -2 sec -1 . In the case of p-n-p transistors the effect was opposite: there was a reduction in the radiation damage by a factor of 2--3 when the dose rate was lowered between the same limits. A similar effect was observed for electrons but at dose rates three orders of magnitude greater. The results were attributed to the dependences of the radiation defect-forming reactions on the charge state of defects which was influenced by the formation of disordered regions in the case of proton irradiation

  4. Diode, transistor & fet circuits manual

    CERN Document Server

    Marston, R M

    2013-01-01

    Diode, Transistor and FET Circuits Manual is a handbook of circuits based on discrete semiconductor components such as diodes, transistors, and FETS. The book also includes diagrams and practical circuits. The book describes basic and special diode characteristics, heat wave-rectifier circuits, transformers, filter capacitors, and rectifier ratings. The text also presents practical applications of associated devices, for example, zeners, varicaps, photodiodes, or LEDs, as well as it describes bipolar transistor characteristics. The transistor can be used in three basic amplifier configuration

  5. Fitted HBT radii versus space-time variances in flow-dominated models

    International Nuclear Information System (INIS)

    Lisa, Mike; Frodermann, Evan; Heinz, Ulrich

    2007-01-01

    The inability of otherwise successful dynamical models to reproduce the 'HBT radii' extracted from two-particle correlations measured at the Relativistic Heavy Ion Collider (RHIC) is known as the 'RHIC HBT Puzzle'. Most comparisons between models and experiment exploit the fact that for Gaussian sources the HBT radii agree with certain combinations of the space-time widths of the source which can be directly computed from the emission function, without having to evaluate, at significant expense, the two-particle correlation function. We here study the validity of this approach for realistic emission function models some of which exhibit significant deviations from simple Gaussian behaviour. By Fourier transforming the emission function we compute the 2-particle correlation function and fit it with a Gaussian to partially mimic the procedure used for measured correlation functions. We describe a novel algorithm to perform this Gaussian fit analytically. We find that for realistic hydrodynamic models the HBT radii extracted from this procedure agree better with the data than the values previously extracted from the space-time widths of the emission function. Although serious discrepancies between the calculated and measured HBT radii remain, we show that a more 'apples-to-apples' comparison of models with data can play an important role in any eventually successful theoretical description of RHIC HBT data. (author)

  6. Conversion Matrix Analysis of SiGe HBT Gilbert Cell Mixers

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Vidkjær, Jens; Krozer, Viktor

    2004-01-01

    The frequency response of SiGe HBT active mixers based on the Gilbert cell topology is analyzed theoretically. The time-varying operation of the Gilbert cell mixer is taken into account by applying conversion matrix analysis. The main bandwidth limiting mechanisms experienced in SiGe HBT Gilbert ...

  7. Synergetic effects of radiation stress and hot-carrier stress on the current gain of npn bipolar junction transistors

    International Nuclear Information System (INIS)

    Witczak, S.C.; Kosier, S.L.; Schrimpf, R.D.; Galloway, K.F.

    1994-01-01

    The combined effects of ionizing radiation and hot-carrier stress on the current gain of npn bipolar junction transistors were investigated. The analysis was carried out experimentally by examining the consequences of interchanging the order in which the two stress types were applied to identical transistors which were stressed to various levels of damage. The results indicate that the hot-carrier response of the transistor is improved by radiation damage, whereas hot-carrier damage has little effect on subsequent radiation stress. Characterization of the temporal progression of hot-carrier effects revealed that hot-carrier stress acts initially to reduce excess base current and improve current gain in irradiated transistors. PISCES simulations show that the magnitude of the peak electric-field within the emitter-base depletion region is reduced significantly by net positive oxide charges induced by radiation. The interaction of the two stress types is explained in a qualitative model based on the probability of hot-carrier injection determined by radiation damage and on the neutralization and compensation of radiation-induced positive oxide charges by injected electrons. The result imply that a bound on damage due to the combined stress types is achieved when hot-carrier stress precedes any irradiation

  8. Experimental study on short-circuit characteristics of the new protection circuit of insulated gate bipolar transistor

    International Nuclear Information System (INIS)

    Ji, In-Hwan; Choi, Young-Hwan; Ha, Min-Woo; Han, Min-Koo; Choi, Yearn-Ik

    2006-01-01

    A new protection circuit employing the collector to emitter voltage (V CE ) sensing scheme for short-circuit withstanding capability of the insulated gate bipolar transistor (IGBT) is proposed and verified by experimental results. Because the current path between the gate and collector can be successfully eliminated in the proposed protection circuit, the power consumption can be reduced and the gate input impedance can be increased. Previous study is limited to dc characteristics. However, experimental results show that the proposed protection circuit successfully reduces the over-current of main IGBT by 80.4% under the short-circuit condition

  9. Low-background transistors for application in nuclear electronics

    International Nuclear Information System (INIS)

    Krasnokutskij, R.N.; Kurchaninov, L.L.; Fedyakin, N.N.; Shuvalov, R.S.

    1988-01-01

    Investigations of silicon transistors were carried out to determine transistors with low value of base distributed resistance (R). Measurement results for R and current amplification coefficient β are presented for bipolar transistor several types. Correlations between R and β were studied. KT 399A, 2T640A and KT3117B transistors are found to be most adequate ones as a base for low-background amplifier development

  10. The Smallest Transistor-Based Nonautonomous Chaotic Circuit

    DEFF Research Database (Denmark)

    Lindberg, Erik; Murali, K.; Tamasevicius, Arunas

    2005-01-01

    A nonautonomous chaotic circuit based on one transistor, two capacitors, and two resistors is described. The mechanism behind the chaotic performance is based on “disturbance of integration.” The forward part and the reverse part of the bipolar transistor are “fighting” about the charging...

  11. On the 50th Anniversary of the Transistor

    DEFF Research Database (Denmark)

    Stassen, Flemming

    1997-01-01

    This paper celebrates the 50th anniversary of the invention of the bipolar transistor in 1947. Combined with the inventions of integration and planar technology, the invention of the transistor marks the beginning of a period of unprecedented growth, the industrialization of electronics....

  12. Parasitic bipolar amplification in a single event transient and its temperature dependence

    International Nuclear Information System (INIS)

    Liu Zheng; Chen Shu-Ming; Chen Jian-Jun; Qin Jun-Rui; Liu Rong-Rong

    2012-01-01

    Using three-dimensional technology computer-aided design (TCAD) simulation, parasitic bipolar amplification in a single event transient (SET) current of a single transistor and its temperature dependence are studied. We quantify the contributions of different current components in a SET current pulse, and it is found that the proportion of parasitic bipolar amplification in total collected charge is about 30% in both 130-nm and 90-nm technologies. The temperature dependence of parasitic bipolar amplification and the mechanism of the SET pulse are also investigated and quantified. The results show that the proportion of charge induced by parasitic bipolar increases with rising temperature, which illustrates that the parasitic bipolar amplification plays an important role in the charge collection of a single transistor

  13. Outlook and Emerging Semiconducting Materials for Ambipolar Transistors

    NARCIS (Netherlands)

    Bisri, Satria Zulkarnaen; Piliego, Claudia; Gao, Jia; Loi, Maria Antonietta

    Ambipolar or bipolar transistors are transistors in which both holes and electrons are mobile inside the conducting channel. This device allows switching among several states: the hole-dominated on-state, the off-state, and the electron-dominated on-state. In the past year, it has attracted great

  14. Substrate Effects in Wideband SiGe HBT Mixer Circuits

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Vidkjær, Jens; Krozer, Viktor

    2005-01-01

    are also applied to predict short distance substrate coupling effects. Simulation results using extracted equivalent circuit models and substrate coupling networks are compared with experimental results obtained on a wideband mixer circuit implemented in a 0.35 μm, 60 GHz ft SiGe HBT BiCMOS process.......In this paper, the influence from substrate effects on the performance of wideband SiGe HBT mixer circuits is investigated. Equivalent circuit models including substrate networks are extracted from on-wafer test structures and compared with electromagnetic simulations. Electromagnetic simulations...

  15. A 38 to 44GHz sub-harmonic balanced HBT mixer with integrated miniature spiral type marchand balun

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Krozer, Viktor

    2013-01-01

    This work presents an active balanced sub-harmonic mixer (SHM) using InP double heterojunction bipolar transistor technology (DHBT) for Q-band applications. A miniature spiral type Marchand balun with five added capacitances for improved control of amplitude and phase balance is integrated with t...

  16. Application of the Johnson criteria to graphene transistors

    International Nuclear Information System (INIS)

    Kelly, M J

    2013-01-01

    For 60 years, the Johnson criteria have guided the development of materials and the materials choices for field-effect and bipolar transistor technology. Intrinsic graphene is a semi-metal, precluding transistor applications, but only under lateral bias is a gap opened and transistor action possible. This first application of the Johnson criteria to biased graphene suggests that this material will struggle to ever achieve competitive commercial applications. (fast track communication)

  17. Programmable automated transistor test system

    International Nuclear Information System (INIS)

    Truong, L.V.; Sundberg, G.R.

    1986-01-01

    The paper describes a programmable automated transistor test system (PATTS) and its utilization to evaluate bipolar transistors and Darlingtons, and such MOSFET and special types as can be accommodated with the PATTS base-drive. An application of a pulsed power technique at low duty cycles in a non-destructive test is used to examine the dynamic switching characteristic curves of power transistors. Data collection, manipulation, storage, and output are operator interactive but are guided and controlled by the system software. In addition a library of test data is established on disks, tapes, and hard copies for future reference

  18. Comparing SiGe HBT Amplifier Circuits for Fast Single-shot Spin Readout

    Science.gov (United States)

    England, Troy; Curry, Matthew; Carr, Stephen; Mounce, Andrew; Jock, Ryan; Sharma, Peter; Bureau-Oxton, Chloe; Rudolph, Martin; Hardin, Terry; Carroll, Malcolm

    Fast, low-power quantum state readout is one of many challenges facing quantum information processing. Single electron transistors (SETs) are potentially fast, sensitive detectors for performing spin readout. From a circuit perspective, however, their output impedance and nonlinear conductance are ill suited to drive the parasitic capacitance of coaxial conductors used in cryogenic environments, necessitating a cryogenic amplification stage. We will compare two amplifiers based on single-transistor circuits implemented with silicon germanium heterojunction bipolar transistors. Both amplifiers provide gain at low power levels, but the dynamics of each circuit vary significantly. We will explore the gain mechanisms, linearity, and noise of each circuit and explain the situations in which each amplifier is best used. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000.

  19. Synergistic effect of mixed neutron and gamma irradiation in bipolar operational amplifier OP07

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Liu, E-mail: liuyan@nint.ac.cn [State Key Laboratory of Intense Pulsed Irradiation Simulation and Effect, Northwest Institute of Nuclear Technology, P.O.Box 69-10, Xi’an 710024 (China); School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Wei, Chen; Shanchao, Yang; Xiaoming, Jin [State Key Laboratory of Intense Pulsed Irradiation Simulation and Effect, Northwest Institute of Nuclear Technology, P.O.Box 69-10, Xi’an 710024 (China); Chaohui, He [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China)

    2016-09-21

    This paper presents the synergistic effects in bipolar operational amplifier OP07. The radiation effects are studied by neutron beam, gamma ray, and mixed neutron/gamma ray environments. The characterateristics of the synergistic effects are studied through comparison of different experiment results. The results show that the bipolar operational amplifier OP07 exhibited significant synergistic effects in the mixed neutron and gamma irradiation. The bipolar transistor is identified as the most radiation sensitive unit of the operational amplifier. In this paper, a series of simulations are performed on bipolar transistors in different radiation environments. In the theoretical simulation, the geometric model and calculations based on the Medici toolkit are built to study the radiation effects in bipolar components. The effect of mixed neutron and gamma irradiation is simulated based on the understanding of the underlying mechanisms of radiation effects in bipolar transistors. The simulated results agree well with the experimental data. The results of the experiments and simulation indicate that the radiation effects in the bipolar devices subjected to mixed neutron and gamma environments is not a simple combination of total ionizing dose (TID) effects and displacement damage. The data suggests that the TID effect could enhance the displacement damage. The synergistic effect should not be neglected in complex radiation environments.

  20. A comparative study on electrical characteristics of 1-kV pnp and npn SiC bipolar junction transistors

    Science.gov (United States)

    Okuda, Takafumi; Kimoto, Tsunenobu; Suda, Jun

    2018-04-01

    We investigate the electrical characteristics of 1-kV pnp SiC bipolar junction transistors (BJTs) and compare them with those of npn SiC BJTs. The base resistance, current gain, and blocking capability are characterized. It is found that the base resistance of pnp SiC BJTs is two orders of magnitude lower than that of npn SiC BJTs. However, the obtained current gains are low below unity in pnp SiC BJTs, whereas npn SiC BJTs exhibit a current gain of 14 without surface passivation. The reason for the poor current gain of pnp SiC BJTs is discussed.

  1. Electro-Thermo-Mechanical Analysis of High-Power Press-Pack Insulated Gate Bipolar Transistors under Various Mechanical Clamping Conditions

    DEFF Research Database (Denmark)

    Hasmasan, Adrian Augustin; Busca, Cristian; Teodorescu, Remus

    2014-01-01

    With the continuously increasing demand for energy and the limited supply of fossil fuels, renewable power sources are becoming ever more important. Knowing that future energy demand will grow, manufacturers are increasing the size of new wind turbines (WTs) in order to reduce the cost of energy...... production. The reliability of the components has a large impact on the overall cost of a WT, and press-pack (PP) insulated gate bipolar transistors (IGBTs) could be a good solution for future multi-megawatt WTs because of advantages like high power density and reliability. When used in power converters, PP...

  2. MOSFET-BJT hybrid mode of the gated lateral bipolar junction transistor for C-reactive protein detection.

    Science.gov (United States)

    Yuan, Heng; Kwon, Hyurk-Choon; Yeom, Se-Hyuk; Kwon, Dae-Hyuk; Kang, Shin-Won

    2011-10-15

    In this study, we propose a novel biosensor based on a gated lateral bipolar junction transistor (BJT) for biomaterial detection. The gated lateral BJT can function as both a BJT and a metal-oxide-semiconductor field-effect transistor (MOSFET) with both the emitter and source, and the collector and drain, coupled. C-reactive protein (CRP), which is an important disease marker in clinical examinations, can be detected using the proposed device. In the MOSFET-BJT hybrid mode, the sensitivity, selectivity, and reproducibility of the gated lateral BJT for biosensors were evaluated in this study. According to the results, in the MOSFET-BJT hybrid mode, the gated lateral BJT shows good selectivity and reproducibility. Changes in the emitter (source) current of the device for CRP antigen detection were approximately 0.65, 0.72, and 0.80 μA/decade at base currents of -50, -30, and -10 μA, respectively. The proposed device has significant application in the detection of certain biomaterials that require a dilution process using a common biosensor, such as a MOSFET-based biosensor. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Base profile design for high-performance operation of bipolar transistors at liquid-nitrogen temperature

    International Nuclear Information System (INIS)

    Stork, J.M.C.; Harame, D.L.; Meyerson, B.S.; Nguyen, T.N.

    1989-01-01

    The base profile requirements of Si bipolar junction transistors (BJT's) high-performance operation at liquid-nitrogen temperature are examined. Measurements of thin epitaxial-base polysilicon-emitter n-p-n transistors with increasing base doping show the effects of bandgap narrowing, mobility changes, and carrier freezeout. At room temperature the collector current at low injection is proportional to the integrated base charge, independent of the impurity distribution. At temperatures below 150 Κ, however, minority injection is dominated by the peak base doping because of the greater effectiveness of bandgap narrowing. When the peak doping in the base approaches 10 19 cm -3 , the bandgap difference between emitter and base is sufficiently small that the current gain no longer monotonically decreases with lower temperature but instead shows a maximum as low as 180 Κ. The device design window appears limited at the low-current end by increased base-emitter leakage due to tunneling and by resistance control at the high-current end. Using the measured dc characteristics, circuit delay calculations are made to estimate the performance of an ECL ring oscillator at room and liquid-nitrogen temperatures. It is shown that if the base doping can be raised to 10 19 cm -3 while keeping the base thickness constant, the minimum delay at liquid nitrogen can approach the delay of optimized devices at room temperature

  4. Fluid phase passivation and polymer encapsulation of InP/InGaAs heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Oxland, R K; Rahman, F

    2008-01-01

    This paper reports on the development of effective passivation techniques for improving and stabilizing the characteristics of InP/InGaAs heterojunction bipolar transistors. Two different methods for carrying out sulfur-based surface passivations are compared. These include exposure to gaseous hydrogen sulfide and immersion treatment in an ammonium sulfide solution. The temporal behaviour of effects resulting from such passivation treatments is reported. It is shown that liquid phase passivation has a larger beneficial effect on device performance than gas phase passivation. This is explained in terms of the polarity of passivating species and the exposed semiconductor surface. Finally, device encapsulation in a novel chalcogenide polymer is shown to be effective in preserving the benefits of surface passivation treatments. The relevant properties of this encapsulation material are also discussed

  5. The effect of fluorine in low thermal budget polysilicon emitters for SiGe heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Schiz, F.J.W.

    1999-03-01

    This thesis investigates the behaviour of fluorine in two types of polysilicon emitter. In the first type the emitter is deposited at 610 deg. C as polycrystalline silicon (p-Si). In the second type the emitter is deposited at 560 deg. C as amorphous silicon (α-Si). The amorphous silicon 1 then regrows to polysilicon during subsequent high temperature anneals. Remarkably different behaviour of fluorine is seen in as-deposited α-Si and as-deposited p-Si emitter bipolar transistors. In the most extreme case, fluorine-implanted as-deposited p-Si devices show a base current increase by a factor of 1.5 and equivalent α-Si devices a base current decrease by a factor of 10.0 compared to unimplanted devices. Cross-section TEM observations are made to study the structure of the polysilicon/silicon interface and SIMS measurements to study the distribution of the fluorine in the polysilicon. The TEM results correlate well with the electrical results and show that fluorine accelerates interfacial oxide breakup. Furthermore, they show that for a given thermal budget, more interfacial oxide breakup and thus more epitaxial regrowth is obtained for transistors with p-Si polysilicon emitters. This results in a lower emitter resistance, for example as low as 12Ωμm 2 for as-deposited p-Si devices. The base current suppression for as-deposited α-Si devices is explained by fluorine passivation of trapping states at the interface. Analysis of the fluorine SIMS profiles suggests that they do not resemble normal diffusion profiles, but are due to fluorine trapped at defects. It is shown that a reciprocal relationship exists between the fluorine dose in the bulk polysilicon layer and the fluorine dose at the interface. In as-deposited α-Si devices, there is more fluorine trapped at defects in the bulk polysilicon layer, so less is available to diffuse to the interface. As a result there is less interfacial oxide breakup and more passivation in the as-deposited α-Si devices. These

  6. Relaxation of Si-SiO2 interfacial stress in bipolar screen oxides due to ionizing radiation

    International Nuclear Information System (INIS)

    Witczak, S.C.; Galloway, K.F.; Schrimpf, R.D.; Suehle, J.S.

    1995-01-01

    Current gain degradation due to ionizing radiation in complementary single-crystalline emitter bipolar transistors was found to grow progressively worse upon subjecting the transistors to repeated cycles of radiation exposure and high-temperature anneal. The increase in radiation sensitivity is independent of the emitter polarity or geometry and is most dramatic between the first and second radiation and anneal cycles. In parallel with the current gain measurements, samples from a monitor wafer simulating the screen oxide region above the extrinsic base in the npn transistors were measured for mechanical stress while undergoing similar cycles of irradiation and anneal. The oxide on the monitor wafer consisted of a 45 nm thermal layer and a 640 nm deposited layer. The results indicate that ionizing radiation helped relieve compressive stress at the Si surface. The magnitude of the stress change due to radiation is smaller than the stress induced by the emitter contact metallization followed by a post-metallization anneal. Correlation of radiation sensitivity in the bipolar transistors and mechanical stress in the monitor wafer suggests that mechanical stress may be influential in determining the radiation hardness of bipolar transistors and lends validation to previously reported observations that Si-SiO 2 interfaces are increasingly more susceptible to radiation damage with decreasing Si compressive stress. Possible mechanisms for the observed changes in stress and their effect on the radiation sensitivity of the bipolar transistors are discussed

  7. The bipolar silicon microstrip detector: A proposal for a novel precision tracking device

    International Nuclear Information System (INIS)

    Horisberger, R.

    1990-01-01

    It is proposed to combine the technology of fully depleted microstrip detectors fabricated on n doped high resistivity silicon with the concept of the bipolar transistor. This is done by adding a n ++ doped region inside the normal p + implanted region of the reverse biased p + n diode. The resulting structure has amplifying properties and is referred to as bipaolar pixel transistor. The simplest readout scheme of a bipolar pixel array by an aluminium strip bus leads to the bipolar microstrip detector. The bipolar pixel structure is expected to give a better signal-to-noise performance for the detection of minimum ionizing charged particle tracks than the normal silicon diode strip detector and therefore should allow in future the fabrication of thinner silicon detectors for precision tracking. (orig.)

  8. Effects of emitter junction and passive base region on low dose rate effect in bipolar devices

    International Nuclear Information System (INIS)

    Pershenkov, V.S.; Cherepko, S.V.; Maslov, V.B.; Belyakov, V.V.; Sogoyan, A.V.; Ulimov, N.; Emelianov, V.V.

    1999-01-01

    Low dose rate effect in bipolar devices consists in the increase of peripheral surface recombination current with dose rate decrease. This is due to the more rapid positive oxide charge and interface trap density build-up as the dose rate becomes lower. High dose rate elevated temperature irradiation is proposed for simulation if the low dose rate effect. In the present we tried to separate the effect of radiation-induced charge in the thick passivation oxide over the emitter junction and passive base regions of npn bipolar transistor. Its goal is to improve bipolar device design for use in space environments and nuclear installations. Three experiments were made during this work. 1. Experiment on radiation-induced charge neutralization (RICN) effect under elevated temperature was performed to show transistor degradation dependence on emitter-base bias. 2. High dose rate elevated and room temperature irradiation of bipolar transistors were performed to separate effects of emitter-junction and passive base regions. 3. Pre- and post- irradiation hydrogen ambient storage was used to investigate its effect on radiation-induced charge build-up over the passive base region. All experiments were performed with npn and pnp transistors. (authors)

  9. Method for double-sided processing of thin film transistors

    Science.gov (United States)

    Yuan, Hao-Chih; Wang, Guogong; Eriksson, Mark A.; Evans, Paul G.; Lagally, Max G.; Ma, Zhenqiang

    2008-04-08

    This invention provides methods for fabricating thin film electronic devices with both front- and backside processing capabilities. Using these methods, high temperature processing steps may be carried out during both frontside and backside processing. The methods are well-suited for fabricating back-gate and double-gate field effect transistors, double-sided bipolar transistors and 3D integrated circuits.

  10. Transistor Small Signal Analysis under Radiation Effects

    International Nuclear Information System (INIS)

    Sharshar, K.A.A.

    2004-01-01

    A Small signal transistor parameters dedicate the operation of bipolar transistor before and after exposed to gamma radiation (1 Mrad up to 5 Mrads) and electron beam(1 MeV, 25 mA) with the same doses as a radiation sources, the electrical parameters of the device are changed. The circuit Model has been discussed.Parameters, such as internal emitter resistance (re), internal base resistance, internal collector resistance (re), emitter base photocurrent (Ippe) and base collector photocurrent (Ippe). These parameters affect on the operation of the device in its applications, which work as an effective element, such as current gain (hFE≡β)degradation it's and effective parameter in the device operation. Also the leakage currents (IcBO) and (IEBO) are most important parameters, Which increased with radiation doses. Theoretical representation of the change in the equivalent circuit for NPN and PNP bipolar transistor were discussed, the input and output parameters of the two types were discussed due to the change in small signal input resistance of the two types. The emitter resistance(re) were changed by the effect of gamma and electron beam irradiation, which makes a change in the role of matching impedances between transistor stages. Also the transistor stability factors S(Ico), S(VBE) and S(β are detected to indicate the transistor operations after exposed to radiation fields. In low doses the gain stability is modified due to recombination of induced charge generated during device fabrication. Also the load resistance values are connected to compensate the effect

  11. Multiple-valued logic design based on the multiple-peak BiCMOS-NDR circuits

    Directory of Open Access Journals (Sweden)

    Kwang-Jow Gan

    2016-06-01

    Full Text Available Three different multiple-valued logic (MVL designs using the multiple-peak negative-differential-resistance (NDR circuits are investigated. The basic NDR element, which is made of several Si-based metal-oxide-semiconductor field-effect-transistor (MOS and SiGe-based heterojunction-bipolar-transistor (HBT devices, can be implemented by using a standard BiCMOS process. These MVL circuits are designed based on the triggering-pulse control, saw-tooth input signal, and peak-control methods, respectively. However, there are some transient states existing between the multiple stable levels for the first two methods. These states might affect the circuit function in practical application. As a result, our proposed peak-control method for the MVL design can be used to overcome these transient states.

  12. Problems posed by the model of bipolar transistor used and the measurement of the parameters associated in the IMAG.1 program

    International Nuclear Information System (INIS)

    Imbrechts, Claude; Le Ber, Jacques

    1969-02-01

    The IMAG-1 program uses, for diodes and transistors, bipolar models of the Ebers and Moll modified type. This model is already used in the US NET.1 program. The object of this paper is essentially to pose the problem of the measurement of the parameters associated with the Ebers and Moll model. However, the authors' ambition is not to solve it but to attract attention to the need to speak the same language to define the model, the methods of measuring the associated parameters and their dispersions in order to better appreciate inaccuracies due to the model's approximations

  13. HBT+: an improved code for finding subhaloes and building merger trees in cosmological simulations

    Science.gov (United States)

    Han, Jiaxin; Cole, Shaun; Frenk, Carlos S.; Benitez-Llambay, Alejandro; Helly, John

    2018-02-01

    Dark matter subhalos are the remnants of (incomplete) halo mergers. Identifying them and establishing their evolutionary links in the form of merger trees is one of the most important applications of cosmological simulations. The HBT (Hierachical Bound-Tracing) code identifies haloes as they form and tracks their evolution as they merge, simultaneously detecting subhaloes and building their merger trees. Here we present a new implementation of this approach, HBT+ , that is much faster, more user friendly, and more physically complete than the original code. Applying HBT+ to cosmological simulations, we show that both the subhalo mass function and the peak-mass function are well fitted by similar double-Schechter functions. The ratio between the two is highest at the high-mass end, reflecting the resilience of massive subhaloes that experience substantial dynamical friction but limited tidal stripping. The radial distribution of the most-massive subhaloes is more concentrated than the universal radial distribution of lower mass subhaloes. Subhalo finders that work in configuration space tend to underestimate the masses of massive subhaloes, an effect that is stronger in the host centre. This may explain, at least in part, the excess of massive subhaloes in galaxy cluster centres inferred from recent lensing observations. We demonstrate that the peak-mass function is a powerful diagnostic of merger tree defects, and the merger trees constructed using HBT+ do not suffer from the missing or switched links that tend to afflict merger trees constructed from more conventional halo finders. We make the HBT+ code publicly available.

  14. Evolution of the MOS transistor - From conception to VLSI

    International Nuclear Information System (INIS)

    Sah, C.T.

    1988-01-01

    Historical developments of the metal-oxide-semiconductor field-effect-transistor (MOSFET) during the last sixty years are reviewed, from the 1928 patent disclosures of the field-effect conductivity modulation concept and the semiconductor triodes structures proposed by Lilienfeld to the 1947 Shockley-originated efforts which led to the laboratory demonstration of the modern silicon MOSFET thirty years later in 1960. A survey is then made of the milestones of the past thirty years leading to the latest submicron silicon logic CMOS (Complementary MOS) and BICMOS (Bipolar-Junction-Transistor CMOS combined) arrays and the three-dimensional and ferroelectric extensions of Dennard's one-transistor dynamic random access memory (DRAM) cell. Status of the submicron lithographic technologies (deep ultra-violet light, X-ray, electron-beam) are summarized. Future trends of memory cell density and logic gate speed are projected. Comparisons of the switching speed of the silicon MOSFET with that of silicon bipolar and GaAs field-effect transistors are reviewed. Use of high-temperature superconducting wires and GaAs-on-Si monolithic semiconductor optical clocks to break the interconnect-wiring delay barrier is discussed. Further needs in basic research and mathematical modeling on the failure mechanisms in submicron silicon transistors at high electric fields (hot electron effects) and in interconnection conductors at high current densities and low as well as high electric fields (electromigration) are indicated

  15. Heat Removal from Bipolar Transistor by Loop Heat Pipe with Nickel and Copper Porous Structures

    Science.gov (United States)

    Smitka, Martin; Malcho, Milan

    2014-01-01

    Loop heat pipes (LHPs) are used in many branches of industry, mainly for cooling of electrical elements and systems. The loop heat pipe is a vapour-liquid phase-change device that transfers heat from evaporator to condenser. One of the most important parts of the LHP is the porous wick structure. The wick structure provides capillary force to circulate the working fluid. To achieve good thermal performance of LHP, capillary wicks with high permeability and porosity and fine pore radius are expected. The aim of this work was to develop porous structures from copper and nickel powder with different grain sizes. For experiment copper powder with grain size of 50 and 100 μm and nickel powder with grain size of 10 and 25 μm were used. Analysis of these porous structures and LHP design are described in the paper. And the measurements' influences of porous structures in LHP on heat removal from the insulated gate bipolar transistor (IGBT) have been made. PMID:24959622

  16. Bipolar-power-transistor-based limiter for high frequency ultrasound imaging systems.

    Science.gov (United States)

    Choi, Hojong; Yang, Hao-Chung; Shung, K Kirk

    2014-03-01

    High performance limiters are described in this paper for applications in high frequency ultrasound imaging systems. Limiters protect the ultrasound receiver from the high voltage (HV) spikes produced by the transmitter. We present a new bipolar power transistor (BPT) configuration and compare its design and performance to a diode limiter used in traditional ultrasound research and one commercially available limiter. Limiter performance depends greatly on the insertion loss (IL), total harmonic distortion (THD) and response time (RT), each of which will be evaluated in all the limiters. The results indicated that, compared with commercial limiter, BPT-based limiter had less IL (-7.7 dB), THD (-74.6 dB) and lower RT (43 ns) at 100 MHz. To evaluate the capability of these limiters, they were connected to a 100 MHz single element transducer and a two-way pulse-echo test was performed. It was found that the -6 dB bandwidth and sensitivity of the transducer using BPT-based limiter were better than those of the commercial limiter by 22% and 140%, respectively. Compared to the commercial limiter, BPT-based limiter is shown to be capable of minimizing signal attenuation, RT and THD at high frequencies and is thus suited for high frequency ultrasound applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Transistor regenerative spectrometer for 14N nuclear quadrupole resonance study

    International Nuclear Information System (INIS)

    Anferov, V.P.; Mikhal'kov, V.M.

    1981-01-01

    Improvement of the Robinson transducer for investigations of nuclear quadrupole resonance (NQR) in 14 N is described. Amplifier of the suggested transducer is made using p-n field effect transistor and small-noise SHF bipolar transistor. Such a circuit permits to obtain optimal relation between input resistance, low-frequency noises and transconductance which provides uniform gain of the transducer in the frequency range of 0.6-12 MHz and permits to construct a transistor spectrometer of NQR not yielding to a lamp spectrometer in sensitivity [ru

  18. Generation of short electrical pulses based on bipolar transistorsny

    Directory of Open Access Journals (Sweden)

    M. Gerding

    2004-01-01

    Full Text Available A system for the generation of short electrical pulses based on the minority carrier charge storage and the step recovery effect of bipolar transistors is presented. Electrical pulses of about 90 ps up to 800 ps duration are generated with a maximum amplitude of approximately 7V at 50Ω. The bipolar transistor is driven into saturation and the base-collector and base-emitter junctions become forward biased. The resulting fast switch-off edge of the transistor’s output signal is the basis for the pulse generation. The fast switching of the transistor occurs as a result of the minority carriers that have been injected and stored across the base-collector junction under forward bias conditions. If the saturated transistor is suddenly reverse biased the pn-junction will appear as a low impedance until the stored charge is depleted. Then the impedance will suddenly increase to its normal high value and the flow of current through the junction will turn to zero, abruptly. A differentiation of the output signal of the transistor results in two short pulses with opposite polarities. The differentiating circuit is implemented by a transmission line network, which mainly acts as a high pass filter. Both the transistor technology (pnp or npn and the phase of the transfer function of the differentating circuit influence the polarity of the output pulses. The pulse duration depends on the transistor parameters as well as on the transfer function of the pulse shaping network. This way of generating short electrical pulses is a new alternative for conventional comb generators based on steprecovery diodes (SRD. Due to the three-terminal structure of the transistor the isolation problem between the input and the output signal of the transistor network is drastically simplified. Furthermore the transistor is an active element in contrast to a SRD, so that its current gain can be used to minimize the power of the driving signal.

  19. Radiation effect on silicon transistors in mixed neutrons-gamma environment

    Science.gov (United States)

    Assaf, J.; Shweikani, R.; Ghazi, N.

    2014-10-01

    The effects of gamma and neutron irradiations on two different types of transistors, Junction Field Effect Transistor (JFET) and Bipolar Junction Transistor (BJT), were investigated. Irradiation was performed using a Syrian research reactor (RR) (Miniature Neutron Source Reactor (MNSR)) and a gamma source (Co-60 cell). For RR irradiation, MCNP code was used to calculate the absorbed dose received by the transistors. The experimental results showed an overall decrease in the gain factors of the transistors after irradiation, and the JFETs were more resistant to the effects of radiation than BJTs. The effect of RR irradiation was also greater than that of gamma source for the same dose, which could be because neutrons could cause more damage than gamma irradiation.

  20. Active feedback control of kink modes in tokamaks: 3D VALEN modeling and HBT-EP experiments

    International Nuclear Information System (INIS)

    Maurer, D.A.

    2002-01-01

    Significant progress in the development of active feedback control as a robust technique for the suppression of the wall stabilized external kink or resistive wall mode (RWM) in tokamaks has been achieved through a combination of modeling and experiments. Results from the 3D feedback modeling code VALEN, which serves as the primary analysis and feedback control design tool for RWM studies on the HBT-EP and DIII-D experiments, are in good agreement with observations. VALEN modeling of proposed advanced control system designs on HBT-EP, DIII-D, NSTX, and FIRE are predicted to approach the ideal wall beta limit in agreement with design principles based on simple single mode analytic theory of RWM feedback control. Benchmark experiments on HBT-EP have shown suppression of plasma disruption at rational edge q values using active feedback control in agreement with model predictions. In addition, the observation in HBT-EP of the plasma amplification of static resonant magnetic fields in plasmas marginally stable to the RWM is in agreement with theory. (author)

  1. Optically switched graphene/4H-SiC junction bipolar transistor

    Science.gov (United States)

    Chandrashekhar, MVS; Sudarshan, Tangali S.; Omar, Sabih U.; Brown, Gabriel; Shetu, Shamaita S.

    2018-05-08

    A bi-polar device is provided, along with methods of making the same. The bi-polar device can include a semiconductor substrate doped with a first dopant, a semiconductor layer on the first surface of the semiconductor substrate, and a Schottky barrier layer on the semiconductor layer. The method of forming a bi-polar device can include: forming a semiconductor layer on a first surface of a semiconductor substrate, where the semiconductor substrate comprises a first dopant and where the semiconductor layer comprises a second dopant that has an opposite polarity than the first dopant; and forming a Schottky barrier layer on a first portion of the semiconductor layer while leaving a second portion of the semiconductor layer exposed.

  2. Electrical properties of InP/InGaAs heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Ouacha, A.

    1993-01-01

    In recent years, there has been considerable interest in indium phosphide (InP) and In-based III-V compounds because of their applications in many electronic and photonic devices. The issues involved in processing high quality InP-based devices have been widely explored during the last decade. Realization of highly reliable, high speed, and long distance fiber-optics communication systems requires good quality of the material growth, characterization techniques and reproducible device processing concepts. All these three elements should be included in the manufacturing sequence in order to produce devices of high quality. Until recently, most of the InP related technologies and advances have been focused around optical fiber communications (1.3-1.55 μm) where Si and GaAs could not compete. The main obstacle to rapid growth of InP based technology in the 80s was the enormous investment and interest of large companies and commercial research organizations in GaAs technology. Supporting and financing InP related devices and material was at best minimal. As a consequence, there has been a much slower perhaps more realistic development curve for non-optical InP-based devices and technologies. InP technology has survived solely on the basic of its technical performance, despite the financial problems. In this thesis, we investigate the static behaviour of InP/InGaAs heterojunction bipolar transistors (HBTs) which have attracted a significant amount of attention. (20 refs., 5 figs., 3 tabs.)

  3. Magnetic Vortex Based Transistor Operations

    Science.gov (United States)

    Kumar, D.; Barman, S.; Barman, A.

    2014-01-01

    Transistors constitute the backbone of modern day electronics. Since their advent, researchers have been seeking ways to make smaller and more efficient transistors. Here, we demonstrate a sustained amplification of magnetic vortex core gyration in coupled two and three vortices by controlling their relative core polarities. This amplification is mediated by a cascade of antivortex solitons travelling through the dynamic stray field. We further demonstrated that the amplification can be controlled by switching the polarity of the middle vortex in a three vortex sequence and the gain can be controlled by the input signal amplitude. An attempt to show fan–out operation yielded gain for one of the symmetrically placed branches which can be reversed by switching the core polarity of all the vortices in the network. The above observations promote the magnetic vortices as suitable candidates to work as stable bipolar junction transistors (BJT). PMID:24531235

  4. Heat Removal from Bipolar Transistor by Loop Heat Pipe with Nickel and Copper Porous Structures

    Directory of Open Access Journals (Sweden)

    Patrik Nemec

    2014-01-01

    Full Text Available Loop heat pipes (LHPs are used in many branches of industry, mainly for cooling of electrical elements and systems. The loop heat pipe is a vapour-liquid phase-change device that transfers heat from evaporator to condenser. One of the most important parts of the LHP is the porous wick structure. The wick structure provides capillary force to circulate the working fluid. To achieve good thermal performance of LHP, capillary wicks with high permeability and porosity and fine pore radius are expected. The aim of this work was to develop porous structures from copper and nickel powder with different grain sizes. For experiment copper powder with grain size of 50 and 100 μm and nickel powder with grain size of 10 and 25 μm were used. Analysis of these porous structures and LHP design are described in the paper. And the measurements’ influences of porous structures in LHP on heat removal from the insulated gate bipolar transistor (IGBT have been made.

  5. Understanding the failure mechanisms of microwave bipolar transistors caused by electrostatic discharge

    Science.gov (United States)

    Jin, Liu; Yongguang, Chen; Zhiliang, Tan; Jie, Yang; Xijun, Zhang; Zhenxing, Wang

    2011-10-01

    Electrostatic discharge (ESD) phenomena involve both electrical and thermal effects, and a direct electrostatic discharge to an electronic device is one of the most severe threats to component reliability. Therefore, the electrical and thermal stability of multifinger microwave bipolar transistors (BJTs) under ESD conditions has been investigated theoretically and experimentally. 100 samples have been tested for multiple pulses until a failure occurred. Meanwhile, the distributions of electric field, current density and lattice temperature have also been analyzed by use of the two-dimensional device simulation tool Medici. There is a good agreement between the simulated results and failure analysis. In the case of a thermal couple, the avalanche current distribution in the fingers is in general spatially unstable and results in the formation of current crowding effects and crystal defects. The experimental results indicate that a collector-base junction is more sensitive to ESD than an emitter-base junction based on the special device structure. When the ESD level increased to 1.3 kV, the collector-base junction has been burnt out first. The analysis has also demonstrated that ESD failures occur generally by upsetting the breakdown voltage of the dielectric or overheating of the aluminum-silicon eutectic. In addition, fatigue phenomena are observed during ESD testing, with devices that still function after repeated low-intensity ESDs but whose performances have been severely degraded.

  6. On the choice of a head element for low-noise bipolar transistor amplifier

    International Nuclear Information System (INIS)

    Krasnokutskij, R.N.; Kurchaninov, L.L.; Fedyakin, N.N.; Shuvalov, R.S.

    1988-01-01

    The measurement results of equivalent noise charge (ENC) for KT382 transistor depending on detector capacity, formation duration and collector current are given. It is shown that the measurement results for this transistor in good agreement with calculations according to the noise model, time-consuming ENC measurements can be replaced by preliminary transistor rejection according to the distributed base resistance, current gain and simple calculations. In applications in the field of nuclear electronics the KT382 transistor enables to attain the same noise parameters as NE578, NE021 transistors (Japan) and it can be recommended for using as a head element of amplifiers

  7. Transistor design considerations for low-noise preamplifiers

    International Nuclear Information System (INIS)

    Fair, R.B.

    1976-01-01

    A review is presented of design considerations for GaAs Schottky-barrier FETs and other types of transistors in low-noise amplifiers for capacitive sources which are used in nuclear radiation detectors and high speed fiber-optic communication systems. Ultimate limits on performance are evaluated in terms of the g/sub m//C/sub i/ ratio and the gate leakage current to minimize the noise sources. Si bipolar transistors and the future prospects of GaAs, Si and InAs MISFETs are discussed, and performance is compared to FETs currently being used in low-noise preamplifiers

  8. High Accuracy Transistor Compact Model Calibrations

    Energy Technology Data Exchange (ETDEWEB)

    Hembree, Charles E. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Mar, Alan [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Robertson, Perry J. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Typically, transistors are modeled by the application of calibrated nominal and range models. These models consists of differing parameter values that describe the location and the upper and lower limits of a distribution of some transistor characteristic such as current capacity. Correspond- ingly, when using this approach, high degrees of accuracy of the transistor models are not expected since the set of models is a surrogate for a statistical description of the devices. The use of these types of models describes expected performances considering the extremes of process or transistor deviations. In contrast, circuits that have very stringent accuracy requirements require modeling techniques with higher accuracy. Since these accurate models have low error in transistor descriptions, these models can be used to describe part to part variations as well as an accurate description of a single circuit instance. Thus, models that meet these stipulations also enable the calculation of quantifi- cation of margins with respect to a functional threshold and uncertainties in these margins. Given this need, new model high accuracy calibration techniques for bipolar junction transis- tors have been developed and are described in this report.

  9. Total Dose Effects on Bipolar Integrated Circuits at Low Temperature

    Science.gov (United States)

    Johnston, A. H.; Swimm, R. T.; Thorbourn, D. O.

    2012-01-01

    Total dose damage in bipolar integrated circuits is investigated at low temperature, along with the temperature dependence of the electrical parameters of internal transistors. Bandgap narrowing causes the gain of npn transistors to decrease far more at low temperature compared to pnp transistors, due to the large difference in emitter doping concentration. When irradiations are done at temperatures of -140 deg C, no damage occurs until devices are warmed to temperatures above -50 deg C. After warm-up, subsequent cooling shows that damage is then present at low temperature. This can be explained by the very strong temperature dependence of dispersive transport in the continuous-time-random-walk model for hole transport. For linear integrated circuits, low temperature operation is affected by the strong temperature dependence of npn transistors along with the higher sensitivity of lateral and substrate pnp transistors to radiation damage.

  10. Structured-gate organic field-effect transistors

    International Nuclear Information System (INIS)

    Aljada, Muhsen; Pandey, Ajay K; Velusamy, Marappan; Burn, Paul L; Meredith, Paul; Namdas, Ebinazar B

    2012-01-01

    We report the fabrication and electrical characteristics of structured-gate organic field-effect transistors consisting of a gate electrode patterned with three-dimensional pillars. The pillar gate electrode was over-coated with a gate dielectric (SiO 2 ) and solution processed organic semiconductors producing both unipolar p-type and bipolar behaviour. We show that this new structured-gate architecture delivers higher source-drain currents, higher gate capacitance per unit equivalent linear channel area, and enhanced charge injection (electrons and/or holes) versus the conventional planar structure in all modes of operation. For the bipolar field-effect transistor (FET) the maximum source-drain current enhancements in p- and n-channel mode were >600% and 28%, respectively, leading to p and n charge mobilities with the same order of magnitude. Thus, we have demonstrated that it is possible to use the FET architecture to manipulate and match carrier mobilities of material combinations where one charge carrier is normally dominant. Mobility matching is advantageous for creating organic logic circuit elements such as inverters and amplifiers. Hence, the method represents a facile and generic strategy for improving the performance of standard organic semiconductors as well as new materials and blends. (paper)

  11. Structured-gate organic field-effect transistors

    Science.gov (United States)

    Aljada, Muhsen; Pandey, Ajay K.; Velusamy, Marappan; Burn, Paul L.; Meredith, Paul; Namdas, Ebinazar B.

    2012-06-01

    We report the fabrication and electrical characteristics of structured-gate organic field-effect transistors consisting of a gate electrode patterned with three-dimensional pillars. The pillar gate electrode was over-coated with a gate dielectric (SiO2) and solution processed organic semiconductors producing both unipolar p-type and bipolar behaviour. We show that this new structured-gate architecture delivers higher source-drain currents, higher gate capacitance per unit equivalent linear channel area, and enhanced charge injection (electrons and/or holes) versus the conventional planar structure in all modes of operation. For the bipolar field-effect transistor (FET) the maximum source-drain current enhancements in p- and n-channel mode were >600% and 28%, respectively, leading to p and n charge mobilities with the same order of magnitude. Thus, we have demonstrated that it is possible to use the FET architecture to manipulate and match carrier mobilities of material combinations where one charge carrier is normally dominant. Mobility matching is advantageous for creating organic logic circuit elements such as inverters and amplifiers. Hence, the method represents a facile and generic strategy for improving the performance of standard organic semiconductors as well as new materials and blends.

  12. Microwave dynamic large signal waveform characterization of advanced InGaP HBT for power amplifiers

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Lixin; Jin Zhi; Liu Xinyu, E-mail: zhaolixin@ime.ac.c [Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029 (China)

    2009-12-15

    In wireless mobile communications and wireless local area networks (WLAN), advanced InGaP HBT with power amplifiers are key components. In this paper, the microwave large signal dynamic waveform characteristics of an advanced InGaP HBT are investigated experimentally for 5.8 GHz power amplifier applications. The microwave large signal waveform distortions at various input power levels, especially at large signal level, are investigated and the reasons are analyzed. The output power saturation is also explained. These analyses will be useful for power amplifier designs. (semiconductor devices)

  13. Analysis of collector-emitter offset voltage of InGaP/GaAs composite collector double heterojunction bipolar transistor

    Science.gov (United States)

    Lew, K. L.; Yoon, S. F.

    2002-04-01

    The Ebers-Moll-like terminal current expressions of a composite collector double heterojunction bipolar transistor (DHBT), which takes the recombination effect into account, have been formulated and an expression for collector-emitter offset voltage [VCE(offset)] has been derived. Factors affecting the VCE(offset) of a composite collector DHBT are investigated and good agreement between the calculated and reported experimental results is shown. Analytical results showed that the transmission coefficient of the base-collector (B-C) junction does not have a considerable effect on the VCE(offset), provided that the B-C junction is of good quality. Thus, despite its asymmetric structure, the VCE(offset) of an optimally designed composite collector DHBT could be as low as that of a conventional DHBT. Hence a composite collector DHBT with low saturation voltage and negligible VCE(offset) is possible if the two conditions: (i) good quality B-C junction, (ii) base transport factor, α≈1, are fulfilled.

  14. HBT interferometry and the parton-hadron phase transition

    International Nuclear Information System (INIS)

    Soff, S.

    2002-01-01

    We discuss predictions for the pion and kaon interferometry measurements in relativistic heavy ion collisions at SPS and RHIC energies. In particular, we confront relativistic transport model calculations that include explicitly a first-order phase transition from a thermalized quark-gluon plasma to a hadron gas with recent data from the RHIC experiments. We critically examine the HBT puzzle both from the theoretical as well as from the experimental point of view. Alternative scenarios are briefly explained. (orig.)

  15. Extreme Temperature Performance of Automotive-Grade Small Signal Bipolar Junction Transistors

    Science.gov (United States)

    Boomer, Kristen; Damron, Benny; Gray, Josh; Hammoud, Ahmad

    2018-01-01

    Electronics designed for space exploration missions must display efficient and reliable operation under extreme temperature conditions. For example, lunar outposts, Mars rovers and landers, James Webb Space Telescope, Europa orbiter, and deep space probes represent examples of missions where extreme temperatures and thermal cycling are encountered. Switching transistors, small signal as well as power level devices, are widely used in electronic controllers, data instrumentation, and power management and distribution systems. Little is known, however, about their performance in extreme temperature environments beyond their specified operating range; in particular under cryogenic conditions. This report summarizes preliminary results obtained on the evaluation of commercial-off-the-shelf (COTS) automotive-grade NPN small signal transistors over a wide temperature range and thermal cycling. The investigations were carried out to establish a baseline on functionality of these transistors and to determine suitability for use outside their recommended temperature limits.

  16. Radiation tolerance of NPN bipolar technology with 30 GHz Ft

    International Nuclear Information System (INIS)

    Flament, O.; Synold, S.; Pontcharra, J. de; Niel, S.

    1999-01-01

    The ionizing dose and neutron radiation tolerance of Si QSA bipolar technology has been investigated. The transistors exhibit good radiation tolerance up to 100 krad and 5 10 13 n/cm 2 without any special fabrication steps to harden the technology to the studied effects. (authors)

  17. Oxide bipolar electronics: materials, devices and circuits

    International Nuclear Information System (INIS)

    Grundmann, Marius; Klüpfel, Fabian; Karsthof, Robert; Schlupp, Peter; Schein, Friedrich-Leonhard; Splith, Daniel; Yang, Chang; Bitter, Sofie; Von Wenckstern, Holger

    2016-01-01

    We present the history of, and the latest progress in, the field of bipolar oxide thin film devices. As such we consider primarily pn-junctions in which at least one of the materials is a metal oxide semiconductor. A wide range of n-type and p-type oxides has been explored for the formation of such bipolar diodes. Since most oxide semiconductors are unipolar, challenges and opportunities exist with regard to the formation of heterojunction diodes and band lineups. Recently, various approaches have led to devices with high rectification, namely p-type ZnCo 2 O 4 and NiO on n-type ZnO and amorphous zinc-tin-oxide. Subsequent bipolar devices and applications such as photodetectors, solar cells, junction field-effect transistors and integrated circuits like inverters and ring oscillators are discussed. The tremendous progress shows that bipolar oxide electronics has evolved from the exploration of various materials and heterostructures to the demonstration of functioning integrated circuits. Therefore a viable, facile and high performance technology is ready for further exploitation and performance optimization. (topical review)

  18. Modelling ionising radiation induced defect generation in bipolar oxides with gated diodes

    International Nuclear Information System (INIS)

    Barnaby, H.J.; Cirba, C.; Schrimpf, R.D.; Kosier, St.; Fouillat, P.; Montagner, X.

    1999-01-01

    Radiation-induced oxide defects that degrade electrical characteristics of bipolar junction transistor (BJTs) can be measured with the use of gated diodes. The buildup of defects and their effect on device radiation response are modeled with computer simulation. (authors)

  19. High-performance silicon nanowire bipolar phototransistors

    Science.gov (United States)

    Tan, Siew Li; Zhao, Xingyan; Chen, Kaixiang; Crozier, Kenneth B.; Dan, Yaping

    2016-07-01

    Silicon nanowires (SiNWs) have emerged as sensitive absorbing materials for photodetection at wavelengths ranging from ultraviolet (UV) to the near infrared. Most of the reports on SiNW photodetectors are based on photoconductor, photodiode, or field-effect transistor device structures. These SiNW devices each have their own advantages and trade-offs in optical gain, response time, operating voltage, and dark current noise. Here, we report on the experimental realization of single SiNW bipolar phototransistors on silicon-on-insulator substrates. Our SiNW devices are based on bipolar transistor structures with an optically injected base region and are fabricated using CMOS-compatible processes. The experimentally measured optoelectronic characteristics of the SiNW phototransistors are in good agreement with simulation results. The SiNW phototransistors exhibit significantly enhanced response to UV and visible light, compared with typical Si p-i-n photodiodes. The near infrared responsivities of the SiNW phototransistors are comparable to those of Si avalanche photodiodes but are achieved at much lower operating voltages. Compared with other reported SiNW photodetectors as well as conventional bulk Si photodiodes and phototransistors, the SiNW phototransistors in this work demonstrate the combined advantages of high gain, high photoresponse, low dark current, and low operating voltage.

  20. Technique for electronic measurement of semi-reduction layer using bipolar transistor of junction

    International Nuclear Information System (INIS)

    Santos, Luiz A.P.; Barros, Fabio R.; Santos, Marcus A.P.; Monte, David S.; Santos, Jose A.P.

    2014-01-01

    Recommendations of the International Commission on Radiological Protection (ICRP), the World Health Organization (WHO) and also of the International Atomic Energy Agency (IAEA) suggest equipment for X-rays diagnosis are checked for conformance to their parameters, such as Layer Semi-Reduction (CSR). The importance of verification of diagnostic radiology in parameters is because of have records that forces patients undergoing radiation doses in some clinics, up to 300% the reference values suggested by international agencies which doses are considered unnecessary, and even harmful, either because of physical or variable greatness of being out of control nominal specification, or the fact of having to repeat the radiographs. In this context, the purpose of this study was an innovative methodology that is the use of bipolar transistor junction (TBJ) to measure the aluminum CSR in diagnostic X-ray equipment beams. Although the TBJ be a device invented in the last century, only in recent years have explored their potential as X-ray sensor applied to diagnosis. The study indicates that the tested device can operating the detection of X-rays is properly polarized with electrical signals that can detect interference of the interaction of X-ray photons with the PN junction formed by the base and emitter terminals. The result of the developed technique was compared to CSR measurements obtained with detection systems standards and it was found that the BJT provides values for aluminum CSR relative errors less than 5%

  1. Charge collection mechanisms in MOS/SOI transistors irradiated by energetic heavy ions

    International Nuclear Information System (INIS)

    Musseau, O.; Leray, J.L.; Ferlet, V.; Umbert, A.; Coic, Y.M.; Hesto, P.

    1991-01-01

    We have investigated with both experimental and numerical methods (Monte Carlo and drift-diffusion models) various charge collection mechanisms in NMOS/SOI transistors irradiated by single energetic heavy ions. Our physical interpretations of data emphasize the influence of various parasitic structures of the device. Two charge collection mechanisms are detailed: substrate funneling in buried MOS capacitor and latching of the parasitic bipolar transistor. Based on carrier transport and charge collection, the sensitivity of future scaled down CMOS/SOI technologies is finally discussed

  2. Germanium content and base doping level influence on extrinsic base resistance and dynamic performances of SiGe:C heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Ramirez-Garcia, E; Valdez-Monroy, L A; Rodriguez-Mendez, L M; Valdez-Perez, D; Galaz-Larios, M C; Enciso-Aguilar, M A; Zerounian, N; Aniel, F

    2014-01-01

    We describe a reliable technique to separate the different contributions to the apparent base resistance (R B  = R Bx  + X R Bi ) of silicon germanium carbon (SiGe:C) heterojunction bipolar transistors (HBTs). The extrinsic base resistance (R Bx ) is quantified using small-signal measurements. The base-collector junction distribution factor (X) and the intrinsic base resistance (R Bi ) are extracted from high frequency noise (MWN) measurements. This method is applied to five different SiGe:C HBTs varying in base doping level and germanium content. The results show that high doping levels improve high frequency noise performances while germanium gradient helps to maintain outstanding dynamic performances. This method could be used to elucidate the base technological configuration that ensures low noise together with remarkable dynamic performances in state-of-the-art SiGe:C HBTs. (paper)

  3. On the Bipolar DC Flow Field-Effect-Transistor for Multifunctional Sample Handing in Microfluidics: A Theoretical Analysis under the Debye–Huckel Limit

    Directory of Open Access Journals (Sweden)

    Weiyu Liu

    2018-02-01

    Full Text Available We present herein a novel method of bipolar field-effect control on DC electroosmosis (DCEO from a physical point of view, in the context of an intelligent and robust operation tool for stratified laminar streams in microscale systems. In this unique design of the DC flow field-effect-transistor (DC-FFET, a pair of face-to-face external gate terminals are imposed with opposite gate-voltage polarities. Diffuse-charge dynamics induces heteropolar Debye screening charge within the diffuse double layer adjacent to the face-to-face oppositely-polarized gates, respectively. A background electric field is applied across the source-drain terminal and forces the face-to-face counterionic charge of reversed polarities into induced-charge electroosmotic (ICEO vortex flow in the lateral direction. The chaotic turbulence of the transverse ICEO whirlpool interacts actively with the conventional plug flow of DCEO, giving rise to twisted streamlines for simultaneous DCEO pumping and ICEO mixing of fluid samples along the channel length direction. A mathematical model in thin-layer approximation and the low-voltage limit is subsequently established to test the feasibility of the bipolar DC-FFET configuration in electrokinetic manipulation of fluids at the micrometer dimension. According to our simulation analysis, an integrated device design with two sets of side-by-side, but upside-down gate electrode pair exhibits outstanding performance in electroconvective pumping and mixing even without any externally-applied pressure difference. Moreover, a paradigm of a microdevice for fully electrokinetics-driven analyte treatment is established with an array of reversed bipolar gate-terminal pairs arranged on top of the dielectric membrane along the channel length direction, from which we can obtain almost a perfect liquid mixture by using a smaller magnitude of gate voltages for causing less detrimental effects at a small Dukhin number. Sustained by theoretical

  4. High current transistor pulse generator

    International Nuclear Information System (INIS)

    Nesterov, V.; Cassel, R.

    1991-05-01

    A solid state pulse generator capable of delivering high current trapezoidally shaped pulses into an inductive load has been developed at SLAC. Energy stored in the capacitor bank of the pulse generator is switched to the load through a pair of Darlington transistors. A combination of diodes and Darlington transistors is used to obtain trapezoidal or triangular shaped current pulses into an inductive load and to recover the remaining energy in the same capacitor bank without reversing capacitor voltage. The transistors work in the switch mode, and the power losses are low. The rack mounted pulse generators presently used at SLAC contain a 660 microfarad storage capacitor bank and can deliver 400 amps at 800 volts into inductive loads up to 3 mH. The pulse generators are used in several different power systems, including pulse to pulse bipolar power supplies and in application with current pulses distributed into different inductive loads. The current amplitude and discharge time are controlled by the central computer system through a specially developed multichannel controller. Several years of operation with the pulse generators have proven their consistent performance and reliability. 8 figs

  5. Outlook and emerging semiconducting materials for ambipolar transistors.

    Science.gov (United States)

    Bisri, Satria Zulkarnaen; Piliego, Claudia; Gao, Jia; Loi, Maria Antonietta

    2014-02-26

    Ambipolar or bipolar transistors are transistors in which both holes and electrons are mobile inside the conducting channel. This device allows switching among several states: the hole-dominated on-state, the off-state, and the electron-dominated on-state. In the past year, it has attracted great interest in exotic semiconductors, such as organic semiconductors, nanostructured materials, and carbon nanotubes. The ability to utilize both holes and electrons inside one device opens new possibilities for the development of more compact complementary metal-oxide semiconductor (CMOS) circuits, and new kinds of optoelectronic device, namely, ambipolar light-emitting transistors. This progress report highlights the recent progresses in the field of ambipolar transistors, both from the fundamental physics and application viewpoints. Attention is devoted to the challenges that should be faced for the realization of ambipolar transistors with different material systems, beginning with the understanding of the importance of interface modification, which heavily affects injections and trapping of both holes and electrons. The recent development of advanced gating applications, including ionic liquid gating, that open up more possibility to realize ambipolar transport in materials in which one type of charge carrier is highly dominant is highlighted. Between the possible applications of ambipolar field-effect transistors, we focus on ambipolar light-emitting transistors. We put this new device in the framework of its prospective for general lightings, embedded displays, current-driven laser, as well as for photonics-electronics interconnection. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. 75 GHz InP DHBT power amplifier based on two-stacked transistors

    DEFF Research Database (Denmark)

    Squartecchia, Michele; Midili, Virginio; Johansen, Tom Keinicke

    2017-01-01

    In this paper we present the design and measurements of a two-stage 75-GHz InP Double Heterojunction Bipolar Transistor (DHBT) power amplifier (PA). An optimized two-stacked transistor power cell has been designed, which represents the building block in the power stage as well as in the driver st......, the power amplifier exhibits a small signal gain of G = 12.6 dB, output power at 1-dB compression of Pout, 1dB = 18.6 dBm and a saturated output power of Psat > 21.4 dBm....

  7. Nonlinear System Analysis in Bipolar Integrated Circuits.

    Science.gov (United States)

    1980-01-01

    H2 (fl,f 6), H2 (f2,f4), and H2 (f3,f4) are all equal, Equation (7-8) can be written as v M(t) = mA2 H2 (fl’-f 2) cos[27(f ,-f2)t] (7-9) The AF...and R. A. AMADORI: Micro- wave Interference Effect in Bipolar Transistors, IEEE Trans. EMC, Vol. EMC-17, pp. 216-219, November 1975. 55. KAPLAN , G

  8. Characterization of ionizing radiation effects in MOS structures by study of bipolar operation; Caracterisation des effets induits par irradiations ionisantes dans des structures MOS a partir de leur fonctionnement en regime bipolaire

    Energy Technology Data Exchange (ETDEWEB)

    Bakhtiar, H. [Univ. Teknologi Malaysia, Dept. of Physics, Johor (Malaysia); Picard, C.; Brisset, C. [CEA Saclay, Lab. d' Electronique et de Technologie de l' Informatique, LETI, 91 - Gif-sur-Yvette (France); Bakhtiar, H.; Hoffmann, A.; Charles, J.P. [Metz Univ., LICM-CLOES-Supelec, 57 (France)

    1999-07-01

    This work presents an original method to characterize radiation effects of micronic transistors. The characterization includes a study of the transistor substrate-drain junction and current gain variation of the bipolar transistor (drain-substrate-source as emitter-base-collector) for different gate voltages. (author000.

  9. A G-band terahertz monolithic integrated amplifier in 0.5-μm InP double heterojunction bipolar transistor technology

    International Nuclear Information System (INIS)

    Li Ou-Peng; Zhang Yong; Xu Rui-Min; Cheng Wei; Wang Yuan; Niu Bing; Lu Hai-Yan

    2016-01-01

    Design and characterization of a G-band (140–220 GHz) terahertz monolithic integrated circuit (TMIC) amplifier in eight-stage common-emitter topology are performed based on the 0.5-μm InGaAs/InP double heterojunction bipolar transistor (DHBT). An inverted microstrip line is implemented to avoid a parasitic mode between the ground plane and the InP substrate. The on-wafer measurement results show that peak gains are 20 dB at 140 GHz and more than 15-dB gain at 140–190 GHz respectively. The saturation output powers are −2.688 dBm at 210 GHz and −2.88 dBm at 220 GHz, respectively. It is the first report on an amplifier operating at the G-band based on 0.5-μm InP DHBT technology. Compared with the hybrid integrated circuit of vacuum electronic devices, the monolithic integrated circuit has the advantage of reliability and consistency. This TMIC demonstrates the feasibility of the 0.5-μm InGaAs/InP DHBT amplifier in G-band frequencies applications. (paper)

  10. A Physics-Based Engineering Methodology for Calculating Soft Error Rates of Bulk CMOS and SiGe Heterojunction Bipolar Transistor Integrated Circuits

    Science.gov (United States)

    Fulkerson, David E.

    2010-02-01

    This paper describes a new methodology for characterizing the electrical behavior and soft error rate (SER) of CMOS and SiGe HBT integrated circuits that are struck by ions. A typical engineering design problem is to calculate the SER of a critical path that commonly includes several circuits such as an input buffer, several logic gates, logic storage, clock tree circuitry, and an output buffer. Using multiple 3D TCAD simulations to solve this problem is too costly and time-consuming for general engineering use. The new and simple methodology handles the problem with ease by simple SPICE simulations. The methodology accurately predicts the measured threshold linear energy transfer (LET) of a bulk CMOS SRAM. It solves for circuit currents and voltage spikes that are close to those predicted by expensive 3D TCAD simulations. It accurately predicts the measured event cross-section vs. LET curve of an experimental SiGe HBT flip-flop. The experimental cross section vs. frequency behavior and other subtle effects are also accurately predicted.

  11. Performance Enhancement of Power Transistors and Radiation effect

    International Nuclear Information System (INIS)

    Hassn, Th.A.A.

    2012-01-01

    The main objective of this scientific research is studying the characteristic of bipolar junction transistor device and its performance under radiation fields and temperature effect as a control element in many power circuits. In this work we present the results of experimental measurements and analytical simulation of gamma – radiation effects on the electrical characteristics and operation of power transistor types 2N3773, 2N3055(as complementary silicon power transistor are designed for general-purpose switching and amplifier applications), three samples of each type were irradiated by gamma radiation with doses, 1 K rad, 5 K rad, 10 K rad, 30 K rad, and 10 Mrad, the experimental data are utilized to establish an analytical relation between the total absorbed dose of gamma irradiation and corresponding to effective density of generated charge in the internal structure of transistor, the electrical parameters which can be measured to estimate the generated defects in the power transistor are current gain, collector current and collected emitter leakage current , these changes cause the circuit to case proper functioning. Collector current and transconductance of each device are calibrated as a function of irradiated dose. Also the threshold voltage and transistor gain can be affected and also calibrated as a function of dose. A silicon NPN power transistor type 2N3773 intended for general purpose applications, were used in this work. It was designed for medium current and high power circuits. Performance and characteristic were discusses under temperature and gamma radiation doses. Also the internal junction thermal system of the transistor represented in terms of a junction thermal resistance (Rjth). The thermal resistance changed by ΔRjth, due to the external intended, also due to the gamma doses intended. The final result from the model analysis reveals that the emitter-bias configuration is quite stable by resistance ratio RB/RE. Also the current

  12. Procedure to derive analytical models for microwave noise performances of Si/SiGe:C and InP/InGaAs heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Ramirez-Garcia, E; Enciso-Aguilar, M A; Aniel, F P; Zerounian, N

    2013-01-01

    We present a useful procedure to derive simplified expressions to model the minimum noise factor and the equivalent noise resistance of Si/SiGe:C and InP/InGaAs heterojunction bipolar transistors (HBTs). An acceptable agreement between models and measurements at operation frequencies up to 18 GHz and at several bias points is demonstrated. The development procedure includes all the significant microwave noise sources of the HBTs. These relations should be useful to model F min and R n for state-of-the-art IV-IV and III–V HBTs. The method is the first step to derive noise analyses formulas valid for operation frequencies near the unitary current gain frequency (f T ); however, to achieve this goal a necessary condition is to have access to HFN measurements up to this frequency regime. (paper)

  13. SiGe HBT linear-in-dB high dynamic range RF envelope detectors and wideband high linearity amplifiers

    OpenAIRE

    Pan, Hsuan-yu

    2010-01-01

    This research work aims on exploiting SiGe HBT technologies in high dynamic range wideband RF linear-in- dB envelope detectors and linear amplifiers. First, an improved all-npn broadband highly linear SiGe HBT differential amplifier is presented based on a variation of Caprio's Quad. A broadband linear amplifier with 46dBm OIP₃ at 20MHz, 34dBm OIP₃ at 1GHz, 6dB noise figure and 10.3dBm P₁dB is demonstrated. Second, an improved exact dynamic model of a fast-settling linear-in-dB Automatic Gain...

  14. Investigation of effective base transit time and current gain modulation of light-emitting transistors under different ambient temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hao-Hsiang; Tu, Wen-Chung; Wang, Hsiao-Lun [Graduate Institute of Photonics and Optoelectronics, National Taiwan University, 1, Roosevelt Road, Sec. 4, Taipei 106, Taiwan (China); Wu, Chao-Hsin, E-mail: chaohsinwu@ntu.edu.tw [Graduate Institute of Photonics and Optoelectronics, National Taiwan University, 1, Roosevelt Road, Sec. 4, Taipei 106, Taiwan (China); Graduate Institute of Electronics Engineering, National Taiwan University, 1, Roosevelt Road, Sec. 4, Taipei106, Taiwan (China)

    2014-11-03

    In this report, the modulation of current gain of InGaP/GaAs light-emitting transistors under different ambient temperatures are measured and analyzed using thermionic emission model of quantum well embedded in the transistor base region. Minority carriers captured by quantum wells gain more energy at high temperatures and escape from quantum wells resulting in an increase of current gain and lower optical output, resulting in different I-V characteristics from conventional heterojunction bipolar transistors. The effect of the smaller thermionic lifetime thus reduces the effective base transit time of transistors at high temperatures. The unique current gain enhancement of 27.61% is achieved when operation temperature increase from 28 to 85 °C.

  15. Contribution to the study of fluctuations in transistors (bipolar and junction field effect types); Contribution a l'etude des fluctuations dans les transistors (bipolaires et a effet champ a jonctions)

    Energy Technology Data Exchange (ETDEWEB)

    Borel, J [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1970-07-01

    A brief review of the basic theory of fluctuations in semiconductors is given: shot, thermal low frequency noise. A measuring set has been built to draw noise spectrums (current or voltage). Noise parameters of bipolar transistors are given, mainly noise voltage. Noise current, noise factor and correlation between noise sources are also calculated. Measurements of noise parameters fit well with theory for various devices made in different technologies: alloyed, mesa, planar. Then we give results of the calculation of noise parameters in a FET starting from a simplified model of the device. Low frequency noise is taken into account. Measurements of the parameters and of the spectrum agree fairly well with the theory. Studies of low frequency noise versus temperature give the density and energy of traps located in the space charge layers and an idea of the impurity encountered in these space charge layers. [French] On rappelle les notions de base de la theorie des fluctuations dans les semiconducteurs: bruit de grenaille, bruit thermique, bruit basse frequence. Un appareillage mis au point pour tracer un spectre de bruit est decrit. On presente ensuite le calcul des parametres de bruit d'un transistor bipolaire en insistant plus particulierement sur la tension de bruit ramenee a l'entree de l'element. Le courant de bruit, le facteur de bruit et la correlation entre les sources de bruit sont calcules. La mesure des parametres de bruit est faite sur divers elements realises dans diverses technologies: alliee, mesa et plane. Les mesures confirment tres bien la theorie. On presente ensuite le calcul des parametres de bruit d'un transistor a effet de champ en definissant un schema equivalent simple de l'element. Le calcul theorique des fluctuations basse frequence est aussi fait. La mesure du spectre de bruit confirme tres bien les calculs theoriques. L'etude du bruit basse frequence en fonction de la temperature permet de remonter a la densite et a l'energie des pieges

  16. Ambipolar nonvolatile memory based on a quantum-dot transistor with a nanoscale floating gate

    International Nuclear Information System (INIS)

    Che, Yongli; Zhang, Yating; Song, Xiaoxian; Cao, Mingxuan; Zhang, Guizhong; Yao, Jianquan; Cao, Xiaolong; Dai, Haitao; Yang, Junbo

    2016-01-01

    Using only solution processing methods, we developed ambipolar quantum-dot (QD) transistor floating-gate memory (FGM) that uses Au nanoparticles as a floating gate. Because of the bipolarity of the active channel of PbSe QDs, the memory could easily trap holes or electrons in the floating gate by programming/erasing (P/E) operations, which could shift the threshold voltage both up and down. As a result, the memory exhibited good programmable memory characteristics: a large memory window (ΔV th  ∼ 15 V) and a long retention time (>10 5  s). The magnitude of ΔV th depended on both P/E voltages and the bias voltage (V DS ): ΔV th was a cubic function to V P/E and linearly depended on V DS . Therefore, this FGM based on a QD transistor is a promising alternative to its inorganic counterparts owing to its advantages of bipolarity, high mobility, low cost, and large-area production.

  17. Silicon-on-Insulator Lateral-Insulated-Gate-Bipolar-Transistor with Built-in Self-anti-ESD Diode

    Directory of Open Access Journals (Sweden)

    Xiaojun Cheng

    2014-05-01

    Full Text Available Power SOI (Silicon-On-Insulator devices have an inherent sandwich structure of MOS (Metal-Oxide-Semiconductor gate which is very easy to suffer ESD (Electro-Static Discharge overstress. To solve this reliability problem, studies on design and modification of a built-in self-anti-ESD diode for a preliminarily optimized high voltage SOI LIGBT (Lateral-Insulated-Gate-Bipolar-Transistor were carried out on the Silvaco TCAD (Technology-Computer-Aided-Design platform. According to the constrains of the technological process, the new introduction of the N+ doped region into P-well region that form the built-in self-anti-ESD diode should be done together with the doping of source under the same mask. The modifications were done by adjusting the vertical impurity profile in P-well into retrograde distribution and designing a cathode plate with a proper length to cover the forward depletion terminal and make sure that the thickness of the cathode plate is the same as that of the gate plate. The simulation results indicate that the modified device structure is compatible with the original one in process and design, the breakdown voltage margin of the former was expanded properly, and both the transient cathode voltages are clamped low enough very quickly. Therefore, the design and optimization results of the modified device structure of the built-in self-anti-ESD diode for the given SOI LIGBT meet the given requirements.

  18. A bipolar analog front-end integrated circuit for the SDC silicon tracker

    International Nuclear Information System (INIS)

    Kipnis, I.; Spieler, H.; Collins, T.

    1993-11-01

    A low-noise, low-power, high-bandwidth, radiation hard, silicon bipolar-transistor full-custom integrated circuit (IC) containing 64 channels of analog signal processing has been developed for the SDC silicon tracker. The IC was designed and tested at LBL and was fabricated using AT ampersand T's CBIC-U2, 4 GHz f T complementary bipolar technology. Each channel contains the following functions: low-noise preamplification, pulse shaping and threshold discrimination. This is the first iteration of the production analog IC for the SDC silicon tracker. The IC is laid out to directly match the 50 μm pitch double-sided silicon strip detector. The chip measures 6.8 mm x 3.1 mm and contains 3,600 transistors. Three stages of amplification provide 180 mV/fC of gain with a 35 nsec peaking time at the comparator input. For a 14 pF detector capacitance, the equivalent noise charge is 1300 el. rms at a power consumption of 1 mW/channel from a single 3.5 V supply. With the discriminator threshold set to 4 times the noise level, a 16 nsec time-walk for 1.25 to 10fC signals is achieved using a time-walk compensation network. Irradiation tests at TRIUMF to a Φ=10 14 protons/cm 2 have been performed on the IC, demonstrating the radiation hardness of the complementary bipolar process

  19. Balanced G-band Gm-boosted frequency doublers in transferred substrate InP HBT technology

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Thualfiqar, Al-Sawaf; Weimann, Nils

    2016-01-01

    In this paper, balanced G-band Gm-boosted frequency doublers in transferred substrate (TS) InP HBT technology are reported for the first time. The Gm-boosted frequency doublers consist of a phase compensated Marchand balun, Gm-boosted doubler stage, and an optional cascode gain stage at the outpu...

  20. Electroluminescence from single-wall carbon nanotube network transistors.

    Science.gov (United States)

    Adam, E; Aguirre, C M; Marty, L; St-Antoine, B C; Meunier, F; Desjardins, P; Ménard, D; Martel, R

    2008-08-01

    The electroluminescence (EL) properties from single-wall carbon nanotube network field-effect transistors (NNFETs) and small bundle carbon nanotube field effect transistors (CNFETs) are studied using spectroscopy and imaging in the near-infrared (NIR). At room temperature, NNFETs produce broad (approximately 180 meV) and structured NIR spectra, while they are narrower (approximately 80 meV) for CNFETs. EL emission from NNFETs is located in the vicinity of the minority carrier injecting contact (drain) and the spectrum of the emission is red shifted with respect to the corresponding absorption spectrum. A phenomenological model based on a Fermi-Dirac distribution of carriers in the nanotube network reproduces the spectral features observed. This work supports bipolar (electron-hole) current recombination as the main mechanism of emission and highlights the drastic influence of carrier distribution on the optoelectronic properties of carbon nanotube films.

  1. A pattern recognition approach to transistor array parameter variance

    Science.gov (United States)

    da F. Costa, Luciano; Silva, Filipi N.; Comin, Cesar H.

    2018-06-01

    The properties of semiconductor devices, including bipolar junction transistors (BJTs), are known to vary substantially in terms of their parameters. In this work, an experimental approach, including pattern recognition concepts and methods such as principal component analysis (PCA) and linear discriminant analysis (LDA), was used to experimentally investigate the variation among BJTs belonging to integrated circuits known as transistor arrays. It was shown that a good deal of the devices variance can be captured using only two PCA axes. It was also verified that, though substantially small variation of parameters is observed for BJT from the same array, larger variation arises between BJTs from distinct arrays, suggesting the consideration of device characteristics in more critical analog designs. As a consequence of its supervised nature, LDA was able to provide a substantial separation of the BJT into clusters, corresponding to each transistor array. In addition, the LDA mapping into two dimensions revealed a clear relationship between the considered measurements. Interestingly, a specific mapping suggested by the PCA, involving the total harmonic distortion variation expressed in terms of the average voltage gain, yielded an even better separation between the transistor array clusters. All in all, this work yielded interesting results from both semiconductor engineering and pattern recognition perspectives.

  2. HBT measurements in relativistic heavy ion collisions

    International Nuclear Information System (INIS)

    Zajc, W.A.

    1990-01-01

    The correlations in relative momentum between identical bosons are determined, in part, by the geometrical properties of the boson source. This fact was first exploited in hadron physics by Goldhaber, Goldhaber, Lee and Pais (GGLP) in 1960. In the intervening three decades, this approach has been applied to lepton-lepton, lepton-hadron, hadron-hadron, and heavy-ion collisions. A word about nomenclature: The correlations in relative momentum between identical mesons arise from Bose statistics. Even previous to GGLP, this fact was applied by Hanbury-Brown and Twiss to measure stellar radii via two-photon interferometry. Thus an alternative name for the GGLP effect is the HBT effect. An informal introduction to Hanbury-Brown-Twiss measurements in heavy ion collisions is presented. The systematic effects in interpreting such data are emphasized, rather than the implications of any single experiment

  3. Ambipolar nonvolatile memory based on a quantum-dot transistor with a nanoscale floating gate

    Energy Technology Data Exchange (ETDEWEB)

    Che, Yongli; Zhang, Yating, E-mail: yating@tju.edu.cn; Song, Xiaoxian; Cao, Mingxuan; Zhang, Guizhong; Yao, Jianquan [Institute of Laser and Opto-Electronics, College of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072 (China); Key Laboratory of Opto-Electronics Information Technology, Ministry of Education, Tianjin University, Tianjin 300072 (China); Cao, Xiaolong [Institute of Laser and Opto-Electronics, College of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072 (China); Key Laboratory of Opto-Electronics Information Technology, Ministry of Education, Tianjin University, Tianjin 300072 (China); College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao 266590 (China); Dai, Haitao [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, School of Science, Tianjin University, Tianjin 300072 (China); Yang, Junbo [Center of Material Science, National University of Defense Technology, Changsha 410073 (China)

    2016-07-04

    Using only solution processing methods, we developed ambipolar quantum-dot (QD) transistor floating-gate memory (FGM) that uses Au nanoparticles as a floating gate. Because of the bipolarity of the active channel of PbSe QDs, the memory could easily trap holes or electrons in the floating gate by programming/erasing (P/E) operations, which could shift the threshold voltage both up and down. As a result, the memory exhibited good programmable memory characteristics: a large memory window (ΔV{sub th} ∼ 15 V) and a long retention time (>10{sup 5 }s). The magnitude of ΔV{sub th} depended on both P/E voltages and the bias voltage (V{sub DS}): ΔV{sub th} was a cubic function to V{sub P/E} and linearly depended on V{sub DS}. Therefore, this FGM based on a QD transistor is a promising alternative to its inorganic counterparts owing to its advantages of bipolarity, high mobility, low cost, and large-area production.

  4. Impact of total ionizing dose on the electromagnetic susceptibility of a single bipolar transistor

    International Nuclear Information System (INIS)

    Doridant, A.; Jarrix, S.; Raoult, J.; Blain, A.; Dusseau, L.; Chatry, N.; Calvel, P.; Hoffmann, P.

    2012-01-01

    Space or military electronic components are subject to both electromagnetic fields and total ionizing dose. This paper deals with the electromagnetic susceptibility of a discrete low frequency transistor subject to total ionizing dose deposition. The electromagnetic susceptibility is investigated on both non-irradiated and irradiated transistors mounted in common emitter configuration. The change in susceptibility to 100 MHz-1.5 GHz interferences lights up a synergy effect between near field electromagnetic waves and total ionizing dose. Physical mechanisms leading to changes in signal output are detailed. (authors)

  5. About influence of buffer porous layers between epitaxial layers of heterostructure on distributions of concentrations of dopants in heterobipolar transistors

    Directory of Open Access Journals (Sweden)

    E Pankratov

    2016-10-01

    Full Text Available In this paper we introduce an approach to manufacture a heterobipolar transistors. Framework this approach we consider doping by diffusion or by ion implantation of required parts of a heterostructure with special configuration and optimization of annealing of dopant and/or radiation defects. In this case one have possibility to manufacture bipolar transistors, which include into itself p-n-junctions with higher sharpness and smaller dimensions. We also consider influence of presents of buffer porous layers between epitaxial layers of heterostructure on distributions of concentrations of dopants in the considered transistors. An approach to decrease value of mismatch-induced stress has been considered.

  6. Bipolar soft connected, bipolar soft disconnected and bipolar soft compact spaces

    Directory of Open Access Journals (Sweden)

    Muhammad Shabir

    2017-06-01

    Full Text Available Bipolar soft topological spaces are mathematical expressions to estimate interpretation of data frameworks. Bipolar soft theory considers the core features of data granules. Bipolarity is important to distinguish between positive information which is guaranteed to be possible and negative information which is forbidden or surely false. Connectedness and compactness are the most important fundamental topological properties. These properties highlight the main features of topological spaces and distinguish one topology from another. Taking this into account, we explore the bipolar soft connectedness, bipolar soft disconnectedness and bipolar soft compactness properties for bipolar soft topological spaces. Moreover, we introduce the notion of bipolar soft disjoint sets, bipolar soft separation, and bipolar soft hereditary property and study on bipolar soft connected and disconnected spaces. By giving the detailed picture of bipolar soft connected and disconnected spaces we investigate bipolar soft compact spaces and derive some results related to this concept.

  7. Twelve-bit 20-GHz reduced size pipeline accumulator in 0.25 µm SiGe:C technology for direct digital synthesiser applications

    DEFF Research Database (Denmark)

    Jensen, Brian Sveistrup; Khafaji, M. Mahdi; Johansen, Tom Keinicke

    2012-01-01

    /Fmax of 180/220 GHz respectively. The accumulator architecture omits the pre-skewing registers of the pipeline, thereby lowering both power consumption and circuit complexity. Some limitations to this design are discussed and the necessary equations for determining the phase jump encountered each time......This article presents a 20 GHz, 12-bit pipeline accumulator with a reduced number of registers, suitable for direct digital synthesizer (DDS) applications. The accumulator is implemented in the IHP SG25H1 (0.25um) SiGe:C technology featuring heterojunction bipolar transistors (HBT) with Ft...... the control word (synthesized frequency) is changed are presented. For many applications employing signal processing after detection, this phase shift can then be corrected for. Compared to a full pipeline architecture, the implemented 12-bit accumulator reduces the number of registers by 55% and the power...

  8. Active Control of 2/1 Magnetic Islands in the HBT-EP Tokamak

    International Nuclear Information System (INIS)

    Navratil, G.A.; Cates, C.; Mauel, M.E.; Maurer, D.; Nadle, D.; Taylor, E.; Xiao, Q.; Wurden, G.A.; Reass, W.A.

    1997-01-01

    Closed and open loop control techniques were applied to growing m/n=2/1 rotating islands in wall stabilized plasmas in the HBT-EP tokamak. The approach taken by HBT-EP combines an adjustable segmented conducting wall (which slows the growth or stabilizes ideal external kinks) with a number of small (6degree wide) saddle coils located between the gaps of the conducting wall. In this paper we report demonstration of 2-phase island rotation control from 5 kHz to 15 kHz and observation of the phase instability which are well modeled by the single-helicity, predictions of nonlinear Rutherford island dynamics for 2/1 tearing modes including important effects of ion inertia and FLR which appears as a damping term in the model equations. The closed loop response of active feedback control of the 2/1 mode at moderate gain was observed to be in good agreement with the theory. We have also demonstrated suppression of the 2/1 island growth using an asynchronous frequency modulation drive which maintains the flow damping of the island by application of rotating control fields with frequencies alternating above and below the natural mode frequency. This frequency modulation control technique was also able to prevent disruptions normally observed to follow giant sawtooth crashes in the plasma core

  9. Long-Term Reliability of SiGe/Si HBTs From Accelerated Lifetime Testing

    Science.gov (United States)

    Bhattacharya, Pallab

    2001-01-01

    Accelerated lifetime tests were performed on double-mesa structure Si(0.7)Ge(0.3)/Si npn heterojunction bipolar transistors, grown by molecular beam epitaxy, in the temperature range of 175 C-275 C. The transistors (with 5x20 sq micron emitter area) have DC current gains approx. 40-50 and f(sub T) and f(sub max) of up to 22 GHz and 25 GHz, respectively. It is found that a gradual degradation in these devices is caused by the recombination enhanced impurity diffusion (REID) of boron atoms from the p-type base region and the associated formation of parasitic energy barriers to electron transport from the emitter to collector layers. This REED has been quantitatively modeled and explained, to the first order of approximation, and the agreement with the measured data is good. The mean time to failure (MTTF) of these devices at room temperature under 1.35 x 10(exp 4) A/sq cm current density operation is estimated from the extrapolation of the Arrhenius plots of device lifetime versus reciprocal temperature. The results of the reliability tests offer valuable feedback for SiGe heterostructure design in order to improve the long-term reliability of the devices and circuits made with them. Hot electron induced degradation of the base-emitter junction was also observed during the accelerated lifetime testing. In order to improve the HBT reliability endangered by the hot electrons, deuterium sintered techniques have been proposed. The preliminary results from this study show that a deuterium-sintered HBT is, indeed, more resistant to hot-electron induced base-emitter junction degradation.

  10. Calculation of comparators of analog-to-digital converters with account of electric regime of transistor operation and ionizing radiation effect; Raschet komparatov analogo-tsifrovykh preobrazovatelej s uchetom ehlektricheskogo rezhima raboty tranzistorov i vozdejstviya ioniziruyushchego izlucheniya

    Energy Technology Data Exchange (ETDEWEB)

    Ragozin, A Yu

    1994-12-31

    Zero shift voltage in comparators of analog-to-digital converters under gamma irradiation with regard to electric mode effect on bipolar transistor degradation is calculated. It is shown that the input range of comparators such weak units are represented by comparators of bipolar and lower grades.

  11. The Fault Detection, Localization, and Tolerant Operation of Modular Multilevel Converters with an Insulated Gate Bipolar Transistor (IGBT Open Circuit Fault

    Directory of Open Access Journals (Sweden)

    Wei Li

    2018-04-01

    Full Text Available Reliability is one of the critical issues for a modular multilevel converter (MMC since it consists of a large number of series-connected power electronics submodules (SMs. In this paper, a complete control strategy including fault detection, localization, and tolerant operation is proposed for the MMC under an insulated gate bipolar transistor (IGBT open circuit fault. According to the output characteristics of the SM with the open-circuit fault of IGBT, a fault detection method based on the circulating current and output current observation is used. In order to further precisely locate the position of the faulty SM, a fault localization method based on the SM capacitor voltage observation is developed. After the faulty SM is isolated, the continuous operation of the converter is ensured by adopting the fault-tolerant strategy based on the use of redundant modules. To verify the proposed fault detection, fault localization, and fault-tolerant operation strategies, a 900 kVA MMC system under the conditions of an IGBT open circuit is developed in the Matlab/Simulink platform. The capabilities of rapid detection, precise positioning, and fault-tolerant operation of the investigated detection and control algorithms are also demonstrated.

  12. Optimization of Vertical Double-Diffused Metal-Oxide Semiconductor (VDMOS) Power Transistor Structure for Use in High Frequencies and Medical Devices.

    Science.gov (United States)

    Farhadi, Rozita; Farhadi, Bita

    2014-01-01

    Power transistors, such as the vertical, double-diffused, metal-oxide semiconductor (VDMOS), are used extensively in the amplifier circuits of medical devices. The aim of this research was to construct a VDMOS power transistor with an optimized structure to enhance the operation of medical devices. First, boron was implanted in silicon by implanting unclamped inductive switching (UIS) and a Faraday shield. The Faraday shield was implanted in order to replace the gate-field parasitic capacitor on the entry part of the device. Also, implanting the UIS was used in order to decrease the effect of parasitic bipolar junction transistor (BJT) of the VDMOS power transistor. The research tool used in this study was Silvaco software. By decreasing the transistor entry resistance in the optimized VDMOS structure, power losses and noise at the entry of the transistor were decreased, and, by increasing the breakdown voltage, the lifetime of the VDMOS transistor lifetime was increased, which resulted in increasing drain flow and decreasing Ron. This consequently resulted in enhancing the operation of high-frequency medical devices that use transistors, such as Radio Frequency (RF) and electrocardiograph machines.

  13. Memristive device based on a depletion-type SONOS field effect transistor

    Science.gov (United States)

    Himmel, N.; Ziegler, M.; Mähne, H.; Thiem, S.; Winterfeld, H.; Kohlstedt, H.

    2017-06-01

    State-of-the-art SONOS (silicon-oxide-nitride-oxide-polysilicon) field effect transistors were operated in a memristive switching mode. The circuit design is a variation of the MemFlash concept and the particular properties of depletion type SONOS-transistors were taken into account. The transistor was externally wired with a resistively shunted pn-diode. Experimental current-voltage curves show analog bipolar switching characteristics within a bias voltage range of ±10 V, exhibiting a pronounced asymmetric hysteresis loop. The experimental data are confirmed by SPICE simulations. The underlying memristive mechanism is purely electronic, which eliminates an initial forming step of the as-fabricated cells. This fact, together with reasonable design flexibility, in particular to adjust the maximum R ON/R OFF ratio, makes these cells attractive for neuromorphic applications. The relative large set and reset voltage around ±10 V might be decreased by using thinner gate-oxides. The all-electric operation principle, in combination with an established silicon manufacturing process of SONOS devices at the Semiconductor Foundry X-FAB, promise reliable operation, low parameter spread and high integration density.

  14. Initial Ferritic Wall Mode studies on HBT-EP

    Science.gov (United States)

    Hughes, Paul; Bialek, J.; Boozer, A.; Mauel, M. E.; Levesque, J. P.; Navratil, G. A.

    2013-10-01

    Low-activation ferritic steels are leading material candidates for use in next-generation fusion development experiments such as a prospective US component test facility and DEMO. Understanding the interaction of plasmas with a ferromagnetic wall will provide crucial physics for these experiments. Although the ferritic wall mode (FWM) was seen in a linear machine, the FWM was not observed in JFT-2M, probably due to eddy current stabilization. Using its high-resolution magnetic diagnostics and positionable walls, HBT-EP has begun exploring the dynamics and stability of plasma interacting with high-permeability ferritic materials tiled to reduce eddy currents. We summarize a simple model for plasma-wall interaction in the presence of ferromagnetic material, describe the design of a recently-installed set of ferritic shell segments, and report initial results. Supported by U.S. DOE Grant DE-FG02-86ER53222.

  15. Gigascale Silicon Photonic Transmitters Integrating HBT-based Carrier-injection Electroabsorption Modulator Structures

    Science.gov (United States)

    Fu, Enjin

    Demand for more bandwidth is rapidly increasing, which is driven by data intensive applications such as high-definition (HD) video streaming, cloud storage, and terascale computing applications. Next-generation high-performance computing systems require power efficient chip-to-chip and intra-chip interconnect yielding densities on the order of 1Tbps/cm2. The performance requirements of such system are the driving force behind the development of silicon integrated optical interconnect, providing a cost-effective solution for fully integrated optical interconnect systems on a single substrate. Compared to conventional electrical interconnect, optical interconnects have several advantages, including frequency independent insertion loss resulting in ultra wide bandwidth and link latency reduction. For high-speed optical transmitter modules, the optical modulator is a key component of the optical I/O channel. This thesis presents a silicon integrated optical transmitter module design based on a novel silicon HBT-based carrier injection electroabsorption modulator (EAM), which has the merits of wide optical bandwidth, high speed, low power, low drive voltage, small footprint, and high modulation efficiency. The structure, mechanism, and fabrication of the modulator structure will be discussed which is followed by the electrical modeling of the post-processed modulator device. The design and realization of a 10Gbps monolithic optical transmitter module integrating the driver circuit architecture and the HBT-based EAM device in a 130nm BiCMOS process is discussed. For high power efficiency, a 6Gbps ultra-low power driver IC implemented in a 130nm BiCMOS process is presented. The driver IC incorporates an integrated 27-1 pseudo-random bit sequence (PRBS) generator for reliable high-speed testing, and a driver circuit featuring digitally-tuned pre-emphasis signal strength. With outstanding drive capability, the driver module can be applied to a wide range of carrier

  16. Effect of 1MeV electron beam on transistors and circuits

    International Nuclear Information System (INIS)

    Lee, Tae Hoon

    1998-02-01

    It has been known that semiconductor devices operating in a radiation environment exhibited significant alterations of their electrical responses. Since an electron beam bombardment produces lattice damage in Si and charged defects in SiO 2 , several electrical parameters of transistors exhibit significant changes. Those parameters are the current gain of BJT (Bipolar Junction Transistor) and the threshold voltage of MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The degradation of transistors brings about that of circuits. This paper presents the results of experiments and simulations performed to study the effects of 1MeV electron beam irradiation on selected silicon transistors and circuits. For BJTs, the current gains of npn (2N3904) and pnp (2N3906) linearly decreased as the irradiation dose increased, and from this result, the damage constants, Ks were obtained as 13.65 for 2N3904 and 22.52 for 2N3906 in MGy, indicating a more stable operation in the electron radiation environment for pnp than that for npn. The decrease of current gain was due to that of minority-carrier lifetime in the base region. For MOSFETs (CD4007s), the threshold voltages of NMOS and PMOS shifted to the lower values, which was resulted from the accumulation of charge in SiO 2 . The charges could be categorized into fixed oxide charge and interfacial trap charge. From experimental results, the amounts of the induced charges could be quantitatively estimated. These degradations of transistors brought about the decrease in the voltage gain of CE (Common Emitter) amplifier and the shifts in the inverting voltage of inverter. Additionally, PSpice simulations of these circuits were carried out by modeling of irradiated transistors. The comparison of simulation with experiment showed the relatively good agreement of simulation for the degradation of circuits after irradiation

  17. Radiation effect of gate controlled lateral PNP BJTs

    International Nuclear Information System (INIS)

    Xi Shanbin; Zhou Dong; Lu Wu; Ren Diyuan; Wen Lin; Sun Jing; Wang Zhikuan

    2012-01-01

    Design and fabricate a new test structure of bipolar device: the gate controlled later PNP bipolar transistor (GCLPNP BJT), then sealed it together with the normal lateral PNP bipolar transistor which is made under the same manufacture process. Then 60 Co-γ radiation effects and annealing behaviors of these two structures are investigated. The results show that the response about base current, collector current, access base current and normalized current gain of GCLPNP bipolar transistor are almost identical to the normal one. Radiation induced defects in the GCLPNP bipolar transistor is separated quantitatively. Studying on the quantitative change of radiation induced defects in the domestic gate controlled bipolar transistor should be a useful way to research the change of radiation induced charges of normal PNP bipolar transistor. (authors)

  18. Atypical transistor-based chaotic oscillators: Design, realization, and diversity

    Science.gov (United States)

    Minati, Ludovico; Frasca, Mattia; OświÈ©cimka, Paweł; Faes, Luca; DroŻdŻ, Stanisław

    2017-07-01

    In this paper, we show that novel autonomous chaotic oscillators based on one or two bipolar junction transistors and a limited number of passive components can be obtained via random search with suitable heuristics. Chaos is a pervasive occurrence in these circuits, particularly after manual adjustment of a variable resistor placed in series with the supply voltage source. Following this approach, 49 unique circuits generating chaotic signals when physically realized were designed, representing the largest collection of circuits of this kind to date. These circuits are atypical as they do not trivially map onto known topologies or variations thereof. They feature diverse spectra and predominantly anti-persistent monofractal dynamics. Notably, we recurrently found a circuit comprising one resistor, one transistor, two inductors, and one capacitor, which generates a range of attractors depending on the parameter values. We also found a circuit yielding an irregular quantized spike-train resembling some aspects of neural discharge and another one generating a double-scroll attractor, which represent the smallest known transistor-based embodiments of these behaviors. Through three representative examples, we additionally show that diffusive coupling of heterogeneous oscillators of this kind may give rise to complex entrainment, such as lag synchronization with directed information transfer and generalized synchronization. The replicability and reproducibility of the experimental findings are good.

  19. Enhanced low dose rate sensitivity (ELDRS) in a voltage comparator which only utilizes complementary vertical NPN and PNP transistors

    International Nuclear Information System (INIS)

    Krieg, J.F.; Titus, J.L.; Emily, D.; Gehlhausen, M.; Swonger, J.; Platteter, D.

    1999-01-01

    For the first time, enhanced low dose rate sensitivity (ELDRS) is reported in a vertical bipolar process. A radiation hardness assurance (RHA) test method was successfully demonstrated on a linear circuit, the HS139RH quad comparator, and its discrete transistor elements. This circuit only uses vertical NPN and PNP transistors. Radiation tests on the HS139RH were performed at 25 C using dose rates of 50 rd(Si)/s, 100 mrd(Si)/s and 10 mrd(Si)/s, and at 100 C using a dose rate of 10 rd(Si)/s. Tests at dose rates of 50 rd(Si)/s at 25 C and 10 rd(Si)/s at 100 C were performed on discrete vertical NPN and PNP transistor elements which comprise the HS139RH. Transistor and circuit responses were evaluated. The die's passivation overcoat layers were varied to examine the effect of removing a nitride layer and thinning a deposited SiO 2 (silox) layer

  20. Transistor Effect in Improperly Connected Transistors.

    Science.gov (United States)

    Luzader, Stephen; Sanchez-Velasco, Eduardo

    1996-01-01

    Discusses the differences between the standard representation and a realistic representation of a transistor. Presents an experiment that helps clarify the explanation of the transistor effect and shows why transistors should be connected properly. (JRH)

  1. Passive stabilization of MHD instabilities at high βn in the HBT-EP Tokamak

    International Nuclear Information System (INIS)

    Gates, D.A.

    1993-01-01

    The HBT-EP Tokamak has been designed, built, and is now fully operational in the Columbia University Plasma Physics Laboratory. One of the primary purposes of this facility is to study the effects of a conducting wall on the MHD modes that lead up to plasma disruptions. Of particular interest are the types of instabilities that are driven by the kinetic pressure of the plasma, because these instabilities are believed to be responsible for the present limit to plasma β with β ∝ /B 2 , where the is the volume averaged pressure and B is the magnetic field. To this end, a movable conducting wall has been installed inside the HBT-EP vacuum chamber. The primary result of this thesis are the initial results from experiments that study the effect of this wall on plasma instabilities. The experiment shows that the conducting wall significantly reduces the growth rate of instabilities that precede a plasma disruption that occurs when the value of β is near the Troyon limit. The location of the wall required for significant stabilization is b/a ∼1.2 where a is the minor radius of the plasma and b is the minor radial location of the wall. Moving the wall closer than b/a = 1.2 slightly degrades the stabilizing effect, which is consistent with recent theories

  2. Passive stabilization of MHD instabilities at high βn in the HBT-EP Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Gates, David A. [Columbia Univ., New York, NY (United States)

    1993-01-01

    The HBT-EP Tokamak has been designed, built, and is now fully operational in the Columbia University Plasma Physics Laboratory. One of the primary purposes of this facility is to study the effects of a conducting wall on the MHD modes that lead up to plasma disruptions. Of particular interest are the types of instabilities that are driven by the kinetic pressure of the plasma, because these instabilities are believed to be responsible for the present limit to plasma β with β ∝/B2, where the is the volume averaged pressure and B is the magnetic field. To this end, a movable conducting wall has been installed inside the HBT-EP vacuum chamber. The primary result of this thesis are the initial results from experiments that study the effect of this wall on plasma instabilities. The experiment shows that the conducting wall significantly reduces the growth rate of instabilities that precede a plasma disruption that occurs when the value of β is near the Troyon limit. The location of the wall required for significant stabilization is b/a ~1.2 where a is the minor radius of the plasma and b is the minor radial location of the wall. Moving the wall closer than b/a = 1.2 slightly degrades the stabilizing effect, which is consistent with recent theories.

  3. Effect of proton and electron-irradiation intensity on radiation-induced damages in silicon bioolar transistors

    International Nuclear Information System (INIS)

    Bannikov, Yu.A.; Gorin, B.M.; Kozhevnikov, V.P.; Mikhnovich, V.V.; Gusev, L.I.

    1981-01-01

    The increase of radiation-induced damages of bipolar n-p-n transistors 8-12 times with the irradiation intensity decrease by protons from 4.07x1010 to 2.5x107 cm-2 x c-1 has been found experimentally. damages of p-n-p transistors vary in the opposite way - they are decreased 2-3 times with the irradiation intensity decrease within the same limits. the dependence of damages on intansity of proton irradiation occurs at the dose rate by three orders less than it has been observed for electron irradiation. the results obtained are explained by the dependence of radiation defectoformation reactions on charge state of defects with account for the role of formation of disordering regions upon proton irradiation [ru

  4. Study on space-time structure of Higgs jet with the HBT correlation method in e{sup +}e{sup -} collision at √(s) = 250 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Hong-ge; Chen, Gang [China University of Geosciences, School of Mathematics and Physics, Wuhan (China); Li, Di-kai [China University of Geosciences, School of Mathematics and Physics, Wuhan (China); Shanghai Jiao Tong University, School of Physics and Astronomy, Shanghai (China); Li, Liang [Shanghai Jiao Tong University, School of Physics and Astronomy, Shanghai (China)

    2017-10-15

    The space-time structure of the Higgs boson decaying into hadron-jets (Higgs jets) is carefully studied with the HBT correlation method using e{sup +}e{sup -} collision events produced by the Monte Carlo generator PYTHIA 8.219 at √(s) = 250 GeV. The measurement of the Higgs boson radius and decay lifetime are derived from the HBT correlation of the final state pions, with an upper bound of R{sub H} ≤ 1.03 ± 0.05 fm and τ{sub H} ≤ (1.29 ± 0.15) x 10{sup -7} fs. This result is consistent with CMS data. (orig.)

  5. SOI Transistor measurement techniques using body contacted transistors

    International Nuclear Information System (INIS)

    Worley, E.R.; Williams, R.

    1989-01-01

    Measurements of body contacted SOI transistors are used to isolate parameters of the back channel and island edge transistor. Properties of the edge and back channel transistor have been measured before and after X-ray irradiation (ARACOR). The unique properties of the edge transistor are shown to be a result of edge geometry as confirmed by a two dimensional transistor simulator

  6. 10 K gate I(2)L and 1 K component analog compatible bipolar VLSI technology - HIT-2

    Science.gov (United States)

    Washio, K.; Watanabe, T.; Okabe, T.; Horie, N.

    1985-02-01

    An advanced analog/digital bipolar VLSI technology that combines on the same chip 2-ns 10 K I(2)L gates with 1 K analog devices is proposed. The new technology, called high-density integration technology-2, is based on a new structure concept that consists of three major techniques: shallow grooved-isolation, I(2)L active layer etching, and I(2)L current gain increase. I(2)L circuits with 80-MHz maximum toggle frequency have developed compatibly with n-p-n transistors having a BV(CE0) of more than 10 V and an f(T) of 5 GHz, and lateral p-n-p transistors having an f(T) of 150 MHz.

  7. Various aspects of ionic machining applied to metallic systems in microwave dipolar transistors

    International Nuclear Information System (INIS)

    Pestie, J.P.; Dumontet, H.; Andrieu, J.P.

    1974-01-01

    The positive benefit of ion bombardment machining in fabricating bipolar microwave transistors is shown. Ion cleaning, especially for P type silicon with high boron concentration allows reproducible surface resistivities to be reached 10 -6 ohms/cm 2 ) and the spurious resistance of the basis to be minimized. Ionic etching of metallic layers allowed 1μm stepped geometric structures to be realized. The multilayer Ti-Pt-Au system was associated to the finest geometries through a finite number of operations [fr

  8. Transistor data book

    International Nuclear Information System (INIS)

    1988-03-01

    It introduces how to use this book. It lists transistor data and index, which are Type No, Cross index, Germanium PNP low power transistors, silicon NPN low power transistors, Germanium PNP high power transistors, Switching transistors, transistor arrays, Miscellaneous transistors, types with U.S military specifications, direct replacement transistors, suggested replacement transistors, schematic drawings, outline drawings, device number keys and manufacturer's logos.

  9. Comparative familial aggregation of bipolar disorder in patients with bipolar I and bipolar II disorders.

    Science.gov (United States)

    Parker, Gordon B; Romano, Mia; Graham, Rebecca K; Ricciardi, Tahlia

    2018-05-01

    We sought to quantify the prevalence and differential prevalence of a bipolar disorder among family members of patients with a bipolar I or II disorder. The sample comprised 1165 bipolar and 1041 unipolar patients, with the former then sub-typed as having either a bipolar I or II condition. Family history data was obtained via an online self-report tool. Prevalence of a family member having a bipolar disorder (of either sub-type) was distinctive (36.8%). Patients with a bipolar I disorder reported a slightly higher family history (41.2%) compared to patients with a bipolar II disorder (36.3%), and with both significantly higher than the rate of bipolar disorder in family members of unipolar depressed patients (18.5%). Findings support the view that bipolar disorder is heritable. The comparable rates in the two bipolar sub-types support the positioning of bipolar II disorder as a valid condition with strong genetic underpinnings.

  10. Evaluation of Anisotropic Biaxial Stress Induced Around Trench Gate of Si Power Transistor Using Water-Immersion Raman Spectroscopy

    Science.gov (United States)

    Suzuki, Takahiro; Yokogawa, Ryo; Oasa, Kohei; Nishiwaki, Tatsuya; Hamamoto, Takeshi; Ogura, Atsushi

    2018-05-01

    The trench gate structure is one of the promising techniques to reduce on-state resistance (R on) for silicon power devices, such as insulated gate bipolar transistors and power metal-oxide-semiconductor field-effect transistors. In addition, it has been reported that stress is induced around the trench gate area, modifying the carrier mobilities. We evaluated the one-dimensional distribution and anisotropic biaxial stress by quasi-line excitation and water-immersion Raman spectroscopy, respectively. The results clearly confirmed anisotropic biaxial stress in state-of-the-art silicon power devices. It is theoretically possible to estimate carrier mobility using piezoresistance coefficients and anisotropic biaxial stress. The electron mobility was increased while the hole mobility was decreased or remained almost unchanged in the silicon (Si) power device. The stress significantly modifies the R on of silicon power transistors. Therefore, their performance can be improved using the stress around the trench gate.

  11. GaAsP/InGaP HBTs grown epitaxially on Si substrates: Effect of dislocation density on DC current gain

    Science.gov (United States)

    Heidelberger, Christopher; Fitzgerald, Eugene A.

    2018-04-01

    Heterojunction bipolar transistors (HBTs) with GaAs0.825P0.175 bases and collectors and In0.40Ga0.60P emitters were integrated monolithically onto Si substrates. The HBT structures were grown epitaxially on Si via metalorganic chemical vapor deposition, using SiGe compositionally graded buffers to accommodate the lattice mismatch while maintaining threading dislocation density at an acceptable level (˜3 × 106 cm-2). GaAs0.825P0.175 is used as an active material instead of GaAs because of its higher bandgap (increased breakdown voltage) and closer lattice constant to Si. Misfit dislocation density in the active device layers, measured by electron-beam-induced current, was reduced by making iterative changes to the epitaxial structure. This optimized process culminated in a GaAs0.825P0.175/In0.40Ga0.60P HBT grown on Si with a DC current gain of 156. By considering the various GaAsP/InGaP HBTs grown on Si substrates alongside several control devices grown on GaAs substrates, a wide range of threading dislocation densities and misfit dislocation densities in the active layers could be correlated with HBT current gain. The effect of threading dislocations on current gain was moderated by the reduction in minority carrier lifetime in the base region, in agreement with existing models for GaAs light-emitting diodes and photovoltaic cells. Current gain was shown to be extremely sensitive to misfit dislocations in the active layers of the HBT—much more sensitive than to threading dislocations. We develop a model for this relationship where increased base current is mediated by Fermi level pinning near misfit dislocations.

  12. Contribution to the study of ionizing radiation effects on bipolar technologies: application to the hardening of integrated circuits

    International Nuclear Information System (INIS)

    Briand, R.

    2001-01-01

    The use of analog integrated circuits in radiation environments raises the problem of their behaviour with respect to the different effects induced by particles and radiations. The first chapter of this thesis presents the origins of radiations and the different topologies of bipolar transistors. The effects of ionizing radiations on bipolar components, like cumulative dose, dose rates, and single events, are detailed in three distinct chapters with the same scientifical approach. The simulation of the physical degradation phenomena of the components allows to establish original electrical models coming from the understanding of the induced mechanisms. These models are used to evaluate the degradations occurring in linear analogic circuits. Common and original hardening methods are presented, some of which are applied to bipolar integrated circuit technologies. Finally, experimental laser beam test techniques are presented, which are used to reproduce the dose rate and the single events. (J.S.)

  13. Electrical characterisation of SiGe heterojunction bipolar transistors and Si pseudo-HBTS

    Science.gov (United States)

    De Barros, O.; Le Tron, B.; Woods, R. C.; Giroult-Matlakowski, G.; Vincent, G.; Brémond, G.

    1996-08-01

    This paper reports an electrical characterisation of the emitter-base junction of Si pseudo-HBTs and SiGe HBTs fabricated in a CMOS compatible single polysilicon self-aligned process. From the reverse characteristics it appears that the definition of the emitter-base junction by plasma etching induces peripheral defects that increase the base current of the transistors. Deep level transient spectroscopy measurements show a deep level in the case of SiGe base, whose spatial origin is not fully determinate up to now.

  14. Physical mechanisms contributing to enhanced bipolar gain degradation at low dose rates

    International Nuclear Information System (INIS)

    Fleetwood, D.M.; Reber, R.A. Jr.; Winokur, P.S.; Kosier, S.L.; Schrimpf, R.D.; Wei, A.; DeLaus, M.; Combs, W.E.; Pease, R.L.

    1994-01-01

    The authors have performed capacitance-voltage (C-V) and thermally-stimulated-current (TSC) measurements on non-radiation-hard MOS capacitors simulating screen oxides of modern bipolar technologies. For 0-V irradiation of ∼25 C, the net trapped-positive-charge density (N ox ) inferred from midgap C-V shifts is ∼25--40% greater for low-dose-rate ( 2 )/s) than for high-dose-rate (> 100 rad(SiO 2 )/s) exposure. Device modeling shows that such a difference in screen-oxide N ox is enough to account for the enhanced low-rate gain degradation often observed in bipolar devices, due to the ∼ exp(N ox 2 ) dependence of the excess base current. At the higher rates, TSC measurements reveal a ∼10% decrease in trapped-hole density over low rates. Also, at high rates, up to ∼2.5-times as many trapped holes are compensated by electrons in border traps than at low rates for these devices and irradiation conditions. Both the reduction in trapped-hole density and increased charge compensation reduce the high-rate midgap shift. A physical model is developed which suggests that both effects are caused by time-dependent space charge in the bulk of these soft oxides associated with slowly transporting and/or metastably trapped holes (e.g., in Eδ' centers). On the basis of this model, bipolar transistors and screen-oxide capacitors were irradiated at 60 C at 200 rad(SiO 2 )/s in a successful effort to match low-rate damage. these surprising results provide insight into enhanced low-rate bipolar gain degradation and suggest potentially promising new approaches to bipolar and BiCMOS hardness assurance for space applications

  15. A novel Tunneling Graphene Nano Ribbon Field Effect Transistor with dual material gate: Numerical studies

    Science.gov (United States)

    Ghoreishi, Seyed Saleh; Saghafi, Kamyar; Yousefi, Reza; Moravvej-farshi, Mohammad Kazem

    2016-09-01

    In this work, we present Dual Material Gate Tunneling Graphene Nano-Ribbon Field Effect Transistors (DMG-T-GNRFET) mainly to suppress the am-bipolar current with assumption that sub-threshold swing which is one of the important characteristics of tunneling transistors must not be degraded. In the proposed structure, dual material gates with different work functions are used. Our investigations are based on numerical simulations which self-consistently solves the 2D Poisson based on an atomistic mode-space approach and Schrodinger equations, within the Non-Equilibrium Green's (NEGF). The proposed device shows lower off-current and on-off ratio becomes 5order of magnitude greater than the conventional device. Also two different short channel effects: Drain Induced Barrier Shortening (DIBS) and hot-electron effect are improved in the proposed device compare to the main structure.

  16. Operational Performance of the Two-Channel 10 Megawatt Feedback Amplifier System for MHD Control on the Columbia University HBT-EP Tokamak

    International Nuclear Information System (INIS)

    Reass, W.A.; Wurden, G.A.

    1997-01-01

    The operational characteristics and performance of the two channel 10 Megawatt MHD feedback control system as installed by Los Alamos National Laboratory on the Columbia University HBT-EP tokamak are described. In the present configuration, driving independent 300 microH saddle coil sets, each channel can deliver 1100 Amperes and 16 kV peak to peak. Full power bandwidth is about 12 kHz, with capabilities at reduced power to 30 kHz. The present system topology is designed to suppress magnetohydrodynamic activity with m=2, n=1 symmetry. Application of either static (single phase) or rotating (twin phased) magnetic perturbations shows the ability to spin up or slow down the plasma, and also prevent (or cause) so-called ''mode-locking''. Open loop and active feedback experiments using a digital signal processor (DSP) have been performed on the HBT-EP tokamak and initial results show the ability to manipulate the plasma MHD mode frequency

  17. Bipolar Treatment: Are Bipolar I and Bipolar II Treated Differently?

    Science.gov (United States)

    ... The diagnosis and management of bipolar I and bipolar II disorders: Clinical practice update. Mayo Clinic Proceedings. 2017;92:1532. Haynes PL, et al. Social rhythm therapies for mood disorders: An update. Current Psychiatry Reports. ...

  18. Is bipolar always bipolar? Understanding the controversy on bipolar disorder in children

    Science.gov (United States)

    Grimmer, Yvonne; Hohmann, Sarah

    2014-01-01

    Dramatically increasing prevalence rates of bipolar disorder in children and adolescents in the United States have provoked controversy regarding the boundaries of manic symptoms in child and adolescent psychiatry. The serious impact of this ongoing debate on the treatment of affected children is reflected in the concomitant increase in prescription rates for antipsychotic medication. A key question in the debate is whether this increase in bipolar disorder in children and adolescents is based on a better detection of early-onset bipolar disorder—which can present differently in children and adolescents—or whether it is caused by an incorrect assignment of symptoms which overlap with other widely known disorders. So far, most findings suggest that the suspected symptoms, in particular chronic, non-episodic irritability (a mood symptom presenting with easy annoyance, temper tantrums and anger) do not constitute a developmental presentation of childhood bipolar disorder. Additional research based on prospective, longitudinal studies is needed to further clarify the developmental trajectories of bipolar disorder and the diagnostic status of chronic, non-episodic irritability. PMID:25580265

  19. Doped Organic Transistors.

    Science.gov (United States)

    Lüssem, Björn; Keum, Chang-Min; Kasemann, Daniel; Naab, Ben; Bao, Zhenan; Leo, Karl

    2016-11-23

    Organic field-effect transistors hold the promise of enabling low-cost and flexible electronics. Following its success in organic optoelectronics, the organic doping technology is also used increasingly in organic field-effect transistors. Doping not only increases device performance, but it also provides a way to fine-control the transistor behavior, to develop new transistor concepts, and even improve the stability of organic transistors. This Review summarizes the latest progress made in the understanding of the doping technology and its application to organic transistors. It presents the most successful doping models and an overview of the wide variety of materials used as dopants. Further, the influence of doping on charge transport in the most relevant polycrystalline organic semiconductors is reviewed, and a concise overview on the influence of doping on transistor behavior and performance is given. In particular, recent progress in the understanding of contact doping and channel doping is summarized.

  20. DeepBipolar: Identifying genomic mutations for bipolar disorder via deep learning.

    Science.gov (United States)

    Laksshman, Sundaram; Bhat, Rajendra Rana; Viswanath, Vivek; Li, Xiaolin

    2017-09-01

    Bipolar disorder, also known as manic depression, is a brain disorder that affects the brain structure of a patient. It results in extreme mood swings, severe states of depression, and overexcitement simultaneously. It is estimated that roughly 3% of the population of the United States (about 5.3 million adults) suffers from bipolar disorder. Recent research efforts like the Twin studies have demonstrated a high heritability factor for the disorder, making genomics a viable alternative for detecting and treating bipolar disorder, in addition to the conventional lengthy and costly postsymptom clinical diagnosis. Motivated by this study, leveraging several emerging deep learning algorithms, we design an end-to-end deep learning architecture (called DeepBipolar) to predict bipolar disorder based on limited genomic data. DeepBipolar adopts the Deep Convolutional Neural Network (DCNN) architecture that automatically extracts features from genotype information to predict the bipolar phenotype. We participated in the Critical Assessment of Genome Interpretation (CAGI) bipolar disorder challenge and DeepBipolar was considered the most successful by the independent assessor. In this work, we thoroughly evaluate the performance of DeepBipolar and analyze the type of signals we believe could have affected the classifier in distinguishing the case samples from the control set. © 2017 Wiley Periodicals, Inc.

  1. Progression along the Bipolar Spectrum: A Longitudinal Study of Predictors of Conversion from Bipolar Spectrum Conditions to Bipolar I and II Disorders

    Science.gov (United States)

    Alloy, Lauren B.; Urošević, Snežana; Abramson, Lyn Y.; Jager-Hyman, Shari; Nusslock, Robin; Whitehouse, Wayne G.; Hogan, Michael

    2011-01-01

    Little longitudinal research has examined progression to more severe bipolar disorders in individuals with “soft” bipolar spectrum conditions. We examine rates and predictors of progression to bipolar I and II diagnoses in a non-patient sample of college-age participants (n = 201) with high General Behavior Inventory scores and childhood or adolescent onset of “soft” bipolar spectrum disorders followed longitudinally for 4.5 years from the Longitudinal Investigation of Bipolar Spectrum (LIBS) project. Of 57 individuals with initial cyclothymia or bipolar disorder not otherwise specified (BiNOS) diagnoses, 42.1% progressed to a bipolar II diagnosis and 10.5% progressed to a bipolar I diagnosis. Of 144 individuals with initial bipolar II diagnoses, 17.4% progressed to a bipolar I diagnosis. Consistent with hypotheses derived from the clinical literature and the Behavioral Approach System (BAS) model of bipolar disorder, and controlling for relevant variables (length of follow-up, initial depressive and hypomanic symptoms, treatment-seeking, and family history), high BAS sensitivity (especially BAS Fun Seeking) predicted a greater likelihood of progression to bipolar II disorder, whereas early age of onset and high impulsivity predicted a greater likelihood of progression to bipolar I (high BAS sensitivity and Fun-Seeking also predicted progression to bipolar I when family history was not controlled). The interaction of high BAS and high Behavioral Inhibition System (BIS) sensitivities also predicted greater likelihood of progression to bipolar I. We discuss implications of the findings for the bipolar spectrum concept, the BAS model of bipolar disorder, and early intervention efforts. PMID:21668080

  2. An accurate two-dimensional LBIC solution for bipolar transistors

    Science.gov (United States)

    Benarab, A.; Baudrand, H.; Lescure, M.; Boucher, J.

    1988-05-01

    A complete solution of the diffusion problem of carriers generated by a located light beam in the emitter and base region of a bipolar structure is presented. Green's function method and moment method are used to solve the 2-D diffusion equation in these regions. From the Green's functions solution of these equations, the light beam induced currents (LBIC) in the different junctions of the structure due to an extended generation represented by a rectangular light spot; are thus decided. The equations of these currents depend both on the parameters which characterise the structure, surface states, dimensions of the emitter and the base region, and the characteristics of the light spot, that is to say, the width and the wavelength. Curves illustrating the variation of the various LBIC in the base region junctions as a function of the impact point of the light beam ( x0) for different values of these parameters are discussed. In particular, the study of the base-emitter currents when the light beam is swept right across the sample illustrates clearly a good geometrical definition of the emitter region up to base end of the emitter-base space-charge areas and a "whirl" lateral diffusion beneath this region, (i.e. the diffusion of the generated carriers near the surface towards the horizontal base-emitter junction and those created beneath this junction towards the lateral (B-E) junctions).

  3. The fitting parameters extraction of conversion model of the low dose rate effect in bipolar devices

    International Nuclear Information System (INIS)

    Bakerenkov, Alexander

    2011-01-01

    The Enhanced Low Dose Rate Sensitivity (ELDRS) in bipolar devices consists of in base current degradation of NPN and PNP transistors increase as the dose rate is decreased. As a result of almost 20-year studying, the some physical models of effect are developed, being described in detail. Accelerated test methods, based on these models use in standards. The conversion model of the effect, that allows to describe the inverse S-shaped excess base current dependence versus dose rate, was proposed. This paper presents the problem of conversion model fitting parameters extraction.

  4. A YinYang bipolar fuzzy cognitive TOPSIS method to bipolar disorder diagnosis.

    Science.gov (United States)

    Han, Ying; Lu, Zhenyu; Du, Zhenguang; Luo, Qi; Chen, Sheng

    2018-05-01

    Bipolar disorder is often mis-diagnosed as unipolar depression in the clinical diagnosis. The main reason is that, different from other diseases, bipolarity is the norm rather than exception in bipolar disorder diagnosis. YinYang bipolar fuzzy set captures bipolarity and has been successfully used to construct a unified inference mathematical modeling method to bipolar disorder clinical diagnosis. Nevertheless, symptoms and their interrelationships are not considered in the existing method, circumventing its ability to describe complexity of bipolar disorder. Thus, in this paper, a YinYang bipolar fuzzy multi-criteria group decision making method to bipolar disorder clinical diagnosis is developed. Comparing with the existing method, the new one is more comprehensive. The merits of the new method are listed as follows: First of all, multi-criteria group decision making method is introduced into bipolar disorder diagnosis for considering different symptoms and multiple doctors' opinions. Secondly, the discreet diagnosis principle is adopted by the revised TOPSIS method. Last but not the least, YinYang bipolar fuzzy cognitive map is provided for the understanding of interrelations among symptoms. The illustrated case demonstrates the feasibility, validity, and necessity of the theoretical results obtained. Moreover, the comparison analysis demonstrates that the diagnosis result is more accurate, when interrelations about symptoms are considered in the proposed method. In a conclusion, the main contribution of this paper is to provide a comprehensive mathematical approach to improve the accuracy of bipolar disorder clinical diagnosis, in which both bipolarity and complexity are considered. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. EDITORIAL: Reigniting innovation in the transistor Reigniting innovation in the transistor

    Science.gov (United States)

    Demming, Anna

    2012-09-01

    Today the transistor is integral to the electronic circuitry that wires our lives. When Bardeen and Brattain first observed an amplified signal by connecting electrodes to a germanium crystal they saw that their 'semiconductor triode' could prove a useful alternative to the more cumbersome vacuum tubes used at the time [1]. But it was perhaps William Schottky who recognized the extent of the transistor's potential. A basic transistor has three or more terminals and current across one pair of terminals can switch or amplify current through another pair. Bardeen, Brattain and Schottky were jointly awarded a Nobel Prize in 1956 'for their researches on semiconductors and their discovery of the transistor effect' [2]. Since then many new forms of the transistor have been developed and understanding of the underlying properties is constantly advancing. In this issue Chen and Shih and colleagues at Taiwan National University and Drexel University report a pyroelectrics transistor. They show how a novel optothermal gating mechanism can modulate the current, allowing a range of developments in nanoscale optoelectronics and wireless devices [3]. The explosion of interest in nanoscale devices in the 1990s inspired electronics researchers to look for new systems that can act as transistors, such as carbon nanotube [4] and silicon nanowire [5] transistors. Generally these transistors function by raising and lowering an energy barrier of kBT -1, but researchers in the US and Canada have demonstrated that the quantum interference between two electronic pathways through aromatic molecules can also modulate the current flow [6]. The device has advantages for further miniaturization where energy dissipation in conventional systems may eventually cause complications. Interest in transistor technology has also led to advances in fabrication techniques for achieving high production quantities, such as printing [7]. Researchers in Florida in the US demonstrated field effect transistor

  6. OPEN-LOOP CONTROL OF A BIPOLAR STEPPER MOTORS USING THE SPECIALIZED INTEGRATED CIRCUITS

    Directory of Open Access Journals (Sweden)

    Gheorghe BALUTA

    2004-12-01

    Full Text Available This paper describes the open-loop control of a stepper motors. Bipolar stepper motors can be driven with an L297, an L298N bridge driver and very few external components. With an L298N this configuration drives motors with winding currents up to 2.5A. If very high powers are required an equivalent circuit made with discrete transistors replaces the bridge driver. Together these two chips form a complete microprocessor-to-stepper motor interface. The command signals for the controller L297 are generated through an IBM-PC486 interface. It was developed an open-loop command program written in BorlandC programming language.

  7. Unijunction transistors

    International Nuclear Information System (INIS)

    1981-01-01

    The electrical characteristics of unijunction transistors can be modified by irradiation with electron beams in excess of 400 KeV and at a dose rate of 10 13 to 10 16 e/cm 2 . Examples are given of the effect of exposing the emitter-base junctions of transistors to such lattice defect causing radiation for a time sufficient to change the valley current of the transistor. (U.K.)

  8. Hetero-gate-dielectric double gate junctionless transistor (HGJLT) with reduced band-to-band tunnelling effects in subthreshold regime

    International Nuclear Information System (INIS)

    Ghosh, Bahniman; Mondal, Partha; Akram, M. W.; Bal, Punyasloka; Salimath, Akshay Kumar

    2014-01-01

    We propose a hetero-gate-dielectric double gate junctionless transistor (HGJLT), taking high-k gate insulator at source side and low-k gate insulator at drain side, which reduces the effects of band-to-band tunnelling (BTBT) in the sub-threshold region. A junctionless transistor (JLT) is turned off by the depletion of carriers in the highly doped thin channel (device layer) which results in a significant band overlap between the valence band of the channel region and the conduction band of the drain region, due to off-state drain bias, that triggers electrons to tunnel from the valence band of the channel region to the conduction band of the drain region leaving behind holes in the channel. These effects of band-to-band tunnelling increase the sub-threshold leakage current, and the accumulation of holes in the channel forms a parasitic bipolar junction transistor (n–p–n BJT for channel JLT) in the lateral direction by the source (emitter), channel (base) and drain (collector) regions in JLT structure in off-state. The proposed HGJLT reduces the subthreshold leakage current and suppresses the parasitic BJT action in off-state by reducing the band-to-band tunnelling probability. (semiconductor devices)

  9. Three-terminal heterojunction bipolar transistor solar cell for high-efficiency photovoltaic conversion.

    Science.gov (United States)

    Martí, A; Luque, A

    2015-04-22

    Here we propose, for the first time, a solar cell characterized by a semiconductor transistor structure (n/p/n or p/n/p) where the base-emitter junction is made of a high-bandgap semiconductor and the collector is made of a low-bandgap semiconductor. We calculate its detailed-balance efficiency limit and prove that it is the same one than that of a double-junction solar cell. The practical importance of this result relies on the simplicity of the structure that reduces the number of layers that are required to match the limiting efficiency of dual-junction solar cells without using tunnel junctions. The device naturally emerges as a three-terminal solar cell and can also be used as building block of multijunction solar cells with an increased number of junctions.

  10. Bipolar disorders

    DEFF Research Database (Denmark)

    Vieta, Eduard; Berk, Michael; Schulze, Thomas G

    2018-01-01

    Bipolar disorders are chronic and recurrent disorders that affect >1% of the global population. Bipolar disorders are leading causes of disability in young people as they can lead to cognitive and functional impairment and increased mortality, particularly from suicide and cardiovascular disease...... and accurate diagnosis is difficult in clinical practice as the onset of bipolar disorder is commonly characterized by nonspecific symptoms, mood lability or a depressive episode, which can be similar in presentation to unipolar depression. Moreover, patients and their families do not always understand...... a bipolar disorder from other conditions. Optimal early treatment of patients with evidence-based medication (typically mood stabilizers and antipsychotics) and psychosocial strategies is necessary....

  11. Neutrality in bipolar structures

    DEFF Research Database (Denmark)

    Montero, Javier; Rodríguez, J. Tinguaro; Franco, Camilo

    2014-01-01

    In this paper, we want to stress that bipolar knowledge representation naturally allows a family of middle states which define as a consequence different kinds of bipolar structures. These bipolar structures are deeply related to the three types of bipolarity introduced by Dubois and Prade, but our...... approach offers a systematic explanation of how such bipolar structures appear and can be identified....

  12. Test simulation of neutron damage to electronic components using accelerator facilities

    Energy Technology Data Exchange (ETDEWEB)

    King, D.B., E-mail: dbking@sandia.gov; Fleming, R.M.; Bielejec, E.S.; McDonald, J.K.; Vizkelethy, G.

    2015-12-15

    The purpose of this work is to demonstrate equivalent bipolar transistor damage response to neutrons and silicon ions. We report on irradiation tests performed at the White Sands Missile Range Fast Burst Reactor, the Sandia National Laboratories (SNL) Annular Core Research Reactor, the SNL SPHINX accelerator, and the SNL Ion Beam Laboratory using commercial silicon npn bipolar junction transistors (BJTs) and III–V Npn heterojunction bipolar transistors (HBTs). Late time and early time gain metrics as well as defect spectra measurements are reported.

  13. The thermodynamics of bipolarity: a bifurcation model of bipolar illness and bipolar character and its psychotherapeutic applications.

    Science.gov (United States)

    Sabelli, H C; Carlson-Sabelli, L; Javaid, J I

    1990-11-01

    Two models dominate current formulations of bipolar illness: the homeostatic model implicit in Freud's psychodynamics and most neuroamine deficit/excess theories; and the oscillatory model of exaggerated biological rhythms. The homeostatic model is based on the closed systems approach of classic thermodynamics, while the oscillatory model requires the open systems approach of modern thermodynamics. Here we present a thermodynamic model of bipolarity that includes both homeostatic and oscillatory features and adds the most important feature of open systems thermodynamics: the creation of novel structures in bifurcation processes. According to the proposed model, bipolarity is the result of exaggerated biological energy that augments homeostatic, oscillatory and creative psychological processes. Only low-energy closed systems tend to rest ("point attractor") and entropic disorder. Open processes containing and exchanging energy fluctuate between opposite states ("periodic attractors"); they are characteristic of most physiological rhythms and are exaggerated in bipolar subjects. At higher energies, their strong fluctuations destroy pre-existing patterns and structures, produce turbulence ("chaotic attractors"), which sudden switches between opposite states, and create new and more complex structures. Likewise, high-energy bipolars develop high spontaneity, great fluctuations between opposite moods, internal and interpersonal chaos, and enhanced creativity (personal, artistic, professional) as well as psychopathology (personality deviations, psychotic delusions). Offered here is a theoretical explanation of the dual--creative and destructive--nature of bipolarity in terms of the new enantiodromic concept of entropy generalized by process theory. Clinically, this article offers an integrative model of bipolarity that accounts for many clinical features and contributes to a definition of the bipolar personality.

  14. Design, construction, and first operational results of a 5 megawatt feedback controlled amplifier system for disruption control on the Columbia University HBT-EP tokamak

    International Nuclear Information System (INIS)

    Reass, W.A.; Alvestad, H.A.; Bartsch, R.R.; Wurden, G.A.; Ivers, T.H.; Nadle, D.L.

    1995-01-01

    This paper presents the electrical design and first operational results of a 5 Megawatt feedback controlled amplifier system designed to drive a 300 uH saddle coil set on the ''HBT-EP'' tokamak. It will be used to develop various plasma feedback techniques to control and inhibit the onset of plasma disruptions that are observed in high ''B'' plasmas. To provide a well characterized system, a high fidelity, high power closed loop amplifier system has been refurbished from the Los Alamos ''ZT-P'' equilibrium feedback system. In it's configuration developed for the Columbia HBT-EP tokamak, any desired waveform may be generated within a I 100 ampere and 16 kV peak to peak dynamic range. An energy storage capacitor bank presently limits the effective full power pulse width to 10 mS. The full power bandwidth driving the saddle coil set is ∼12 kHz, with bandwidth at reduced powers exceeding 30 kHz. The system is designed similar to a grounded cathode, push-pull, transformer coupled, tube type amplifier system. 'Me push pull amplifier consists of 6 each Machlett ML8618 magnetically beamed triodes, 3 on each end of the (center tapped) coupling transformer. The transformer has .I volt-seconds of core and a 1:1 turns ratio. The transformer is specially designed for high power, low leakage inductance, and high bandwidth. Each array of ML8618's is (grid) driven with a fiber optic controlled hotdeck with a 3CXI0,000A7 (triode) output. To linearize the ML8618 grid drive, a minor feedback loop in the hotdeck is utilized. Overall system response is controlled by active feedback of the saddle coil current, derived from a coaxial current viewing resistor. The detailed electrical design of the power amplifier, transformer, and feedback system will be provided in addition to recent HBT-EP operational results

  15. Bipolar disorder in adolescence.

    Science.gov (United States)

    DeFilippis, Melissa; Wagner, Karen Dineen

    2013-08-01

    Bipolar disorder is a serious psychiatric condition that may have onset in childhood. It is important for physicians to recognize the symptoms of bipolar disorder in children and adolescents in order to accurately diagnose this illness early in its course. Evidence regarding the efficacy of various treatments is necessary to guide the management of bipolar disorder in youth. For example, several medications commonly used for adults with bipolar disorder have not shown efficacy for children and adolescents with bipolar disorder. This article reviews the prevalence, diagnosis, course, and treatment of bipolar disorder in children and adolescents and provides physicians with information that will aid in diagnosis and treatment.

  16. Giant electron-hole transport asymmetry in ultra-short quantum transistors

    Science.gov (United States)

    McRae, A. C.; Tayari, V.; Porter, J. M.; Champagne, A. R.

    2017-01-01

    Making use of bipolar transport in single-wall carbon nanotube quantum transistors would permit a single device to operate as both a quantum dot and a ballistic conductor or as two quantum dots with different charging energies. Here we report ultra-clean 10 to 100 nm scale suspended nanotube transistors with a large electron-hole transport asymmetry. The devices consist of naked nanotube channels contacted with sections of tube under annealed gold. The annealed gold acts as an n-doping top gate, allowing coherent quantum transport, and can create nanometre-sharp barriers. These tunnel barriers define a single quantum dot whose charging energies to add an electron or a hole are vastly different (e−h charging energy asymmetry). We parameterize the e−h transport asymmetry by the ratio of the hole and electron charging energies ηe−h. This asymmetry is maximized for short channels and small band gap tubes. In a small band gap device, we demonstrate the fabrication of a dual functionality quantum device acting as a quantum dot for holes and a much longer quantum bus for electrons. In a 14 nm-long channel, ηe−h reaches up to 2.6 for a device with a band gap of 270 meV. The charging energies in this device exceed 100 meV. PMID:28561024

  17. Bipolar Disorder

    Science.gov (United States)

    Bipolar disorder is a serious mental illness. People who have it go through unusual mood changes. They go ... The down feeling is depression. The causes of bipolar disorder aren't always clear. It runs in families. ...

  18. Effect of 50 MeV Li3+ ion irradiation on electrical characteristics of high speed NPN power transistor

    International Nuclear Information System (INIS)

    Dinesh, C.M.; Ramani; Radhakrishna, M.C.; Dutt, R.N.; Khan, S.A.; Kanjilal, D.

    2008-01-01

    Silicon NPN overlay RF power high speed commercial bipolar junction transistors (BJTs) find applications in military, space and communication equipments. Here we report the effect of 50 MeV Li 3+ ion irradiation in the fluence range 1 x 10 11 -1.8 x 10 12 ions cm -2 on NPN power transistor. The range (R), electronic energy loss (S e ), nuclear energy loss (S n ), total ionizing dose (TID) and total displacement damage (D d ) in the silicon target are calculated from TRIM Monte Carlo Code. Output resistance is 3.568 x 10 4 Ω for unirradiated device and it increases to 6 x 10 7 Ω as the fluence is increased from 1 x 10 11 to 1.8 x 10 12 ions cm -2 . The capacitance of the emitter-base junction of the transistor decreases and dielectric loss of the emitter-base junction increases with increase in ion fluence. The built in voltage of the unirradiated sample is 0.5 V and it shifts to 0.4 V after irradiation at fluence of 1.8 x 10 12 ions cm -2 and the corresponding doping density reduced to 5.758 x 10 16 cm -3 . The charge carrier removal rate varies linearly with the increase in ion fluence

  19. Copper atomic-scale transistors.

    Science.gov (United States)

    Xie, Fangqing; Kavalenka, Maryna N; Röger, Moritz; Albrecht, Daniel; Hölscher, Hendrik; Leuthold, Jürgen; Schimmel, Thomas

    2017-01-01

    We investigated copper as a working material for metallic atomic-scale transistors and confirmed that copper atomic-scale transistors can be fabricated and operated electrochemically in a copper electrolyte (CuSO 4 + H 2 SO 4 ) in bi-distilled water under ambient conditions with three microelectrodes (source, drain and gate). The electrochemical switching-on potential of the atomic-scale transistor is below 350 mV, and the switching-off potential is between 0 and -170 mV. The switching-on current is above 1 μA, which is compatible with semiconductor transistor devices. Both sign and amplitude of the voltage applied across the source and drain electrodes ( U bias ) influence the switching rate of the transistor and the copper deposition on the electrodes, and correspondingly shift the electrochemical operation potential. The copper atomic-scale transistors can be switched using a function generator without a computer-controlled feedback switching mechanism. The copper atomic-scale transistors, with only one or two atoms at the narrowest constriction, were realized to switch between 0 and 1 G 0 ( G 0 = 2e 2 /h; with e being the electron charge, and h being Planck's constant) or 2 G 0 by the function generator. The switching rate can reach up to 10 Hz. The copper atomic-scale transistor demonstrates volatile/non-volatile dual functionalities. Such an optimal merging of the logic with memory may open a perspective for processor-in-memory and logic-in-memory architectures, using copper as an alternative working material besides silver for fully metallic atomic-scale transistors.

  20. Novel multiple criteria decision making methods based on bipolar neutrosophic sets and bipolar neutrosophic graphs

    OpenAIRE

    Muhammad, Akram; Musavarah, Sarwar

    2016-01-01

    In this research study, we introduce the concept of bipolar neutrosophic graphs. We present the dominating and independent sets of bipolar neutrosophic graphs. We describe novel multiple criteria decision making methods based on bipolar neutrosophic sets and bipolar neutrosophic graphs. We also develop an algorithm for computing domination in bipolar neutrosophic graphs.

  1. Enchanced total dose damage in junction field effect transistors and related linear integrated circuits

    International Nuclear Information System (INIS)

    Flament, O.; Autran, J.L.; Roche, P.; Leray, J.L.; Musseau, O.

    1996-01-01

    Enhanced total dose damage of Junction Field-effect Transistors (JFETs) due to low dose rate and/or elevated temperature has been investigated for elementary p-channel structures fabricated on bulk and SOI substrates as well as for related linear integrated circuits. All these devices were fabricated with conventional junction isolation (field oxide). Large increases in damage have been revealed by performing high temperature and/or low dose rate irradiations. These results are consistent with previous studies concerning bipolar field oxides under low-field conditions. They suggest that the transport of radiation-induced holes through the oxide is the underlying mechanism. Such an enhanced degradation must be taken into account for low dose rate effects on linear integrated circuits

  2. Dual-Gate p-GaN Gate High Electron Mobility Transistors for Steep Subthreshold Slope.

    Science.gov (United States)

    Bae, Jong-Ho; Lee, Jong-Ho

    2016-05-01

    A steep subthreshold slope characteristic is achieved through p-GaN gate HEMT with dual-gate structure. Obtained subthreshold slope is less than 120 μV/dec. Based on the measured and simulated data obtained from single-gate device, breakdown of parasitic floating-base bipolar transistor and floating gate charged with holes are responsible to increase abruptly in drain current. In the dual-gate device, on-current degrades with high temperature but subthreshold slope is not changed. To observe the switching speed of dual-gate device and transient response of drain current are measured. According to the transient responses of drain current, switching speed of the dual-gate device is about 10(-5) sec.

  3. Modelling, development and optimization of integrated power LDMOS transistor. Performance limits in terms of energy; Modelisation, conception et optimisation de composant de puissance lateral DMOS integre. Etude des limites de performance en energie

    Energy Technology Data Exchange (ETDEWEB)

    Farenc, D.

    1997-12-16

    Technologies for Smart Power Integrated Circuits combine into a single chip Bipolar and CMOS transistors, plus power with lateral or vertical DMOS transistors. Complexity which has been increasing dramatically since the mid-80`s has allowed to integrate, into a single monolithic solution, entire systems. This thesis deals with the modelling, conception and test of the power integrated LDMOS transistor. The power LDMOS transistor is used as a switching device. It is characterized by two parameters which are the Specific On-resistance R{sub sp} and the breakdown voltage BV{sub DSS}. The LDMOS transistor developed for the new Smart Power technology exhibits a Specific On-resistance of 200 m{Omega}{sup *}mm{sup 2} and a breakdown voltage of 60 V. This device is dedicated to automotive applications. A reduction of the power device which is achieved with a low Specific On-resistance puts forward new issues such as the maximum Energy capability. When the power device is switched-off on an inductive load, a certain amount of energy is dissipated; if it is beyond a certain limit, the device is destroyed. Our goal is to determine the energy limits which are associated with our new Power integrated LDMOS transistor. (author) 28 refs.

  4. Imunologia do transtorno bipolar Immunology of bipolar disorder

    Directory of Open Access Journals (Sweden)

    Izabela Guimarães Barbosa

    2009-01-01

    Full Text Available OBJETIVO: Pesquisas recentes têm implicado fatores imunes na patogênese de diversos transtornos neuropsiquiátricos. O objetivo do presente trabalho é revisar os trabalhos que investigaram a associação entre transtorno bipolar e alterações em parâmetros imunes. MÉTODOS: Artigos que incluíam as palavras-chave: "bipolar disorder", "mania", "immunology", "cytokines", "chemokines", "interleukins", "interferon" e "tumor necrosis factor" foram selecionados em uma revisão sistemática da literatura. As bases de dados avaliadas foram MedLine e Scopus, entre os anos de 1980 e 2008. RESULTADOS: Foram identificados 28 trabalhos que estudaram alterações imunes em pacientes com transtorno bipolar. Seis artigos investigaram genes relacionados à resposta imune; cinco, autoanticorpos; quatro, populações leucocitárias; 13, citocinas e/ou moléculas relacionadas à resposta imune e seis, leucócitos de pacientes in vitro. CONCLUSÕES: Embora haja evidências na literatura correlacionando o transtorno bipolar a alterações imunes, os dados não são conclusivos. O transtorno bipolar parece estar associado a níveis mais elevados de autoanticorpos circulantes, assim como à tendência à ativação imune com produção de citocinas pró-inflamatórias e redução de parâmetros anti-inflamatórios.OBJECTIVE: Emerging research has implicated immune factors in the pathogenesis of a variety of neuropsychiatric disorders. The objective of the present paper is to review the studies that investigated the association between bipolar disorder and immune parameters. METHODS: Papers that included the keywords "bipolar to disorder", "mania", "immunology", "cytokines", "chemokines", "interleukins", "interferon" and "tumor necrosis factor" were selected in a systematic review of the literature. The evaluated databases were MedLine and Scopus in the period between 1980 and 2008. RESULTS: Twenty eight works were found. Six studies investigated immune response

  5. Akkumulation von L-Malat und D-Lactat in Arabidopsis thaliana und Laccase/HBT-vermittelte Delignifizierung von Spartina alterniflora und Phragmites australis

    OpenAIRE

    Heil, Alexander

    2016-01-01

    The current work contains two projects "Accumulation of L-malate and D-lactate in Arabidopsis thaliana" (A) "Laccase/HBT mediated delignification of Spartina alterniflora and Phragmites australis" (B). In project A, L-malate and D-lactate accumulated in A. thaliana plants. The accumulation of L-malate is carried out by modification of the plant metabolism with the enzymes PEPC, MDH and the tonoplast dicarboxylate transporter (TDT). Gene pepci2 (Hydrilla verticillata), mdh5 (Zea mays) and tdt ...

  6. Genetic structure of personality factors and bipolar disorder in families segregating bipolar disorder.

    Science.gov (United States)

    Hare, Elizabeth; Contreras, Javier; Raventos, Henriette; Flores, Deborah; Jerez, Alvaro; Nicolini, Humberto; Ontiveros, Alfonso; Almasy, Laura; Escamilla, Michael

    2012-02-01

    Bipolar disorder (BPD) has been associated with variations in personality dimensions, but the nature of this relationship has been unclear. In this study, the heritabilities of BPD and the Big Five personality factors and the genetic correlations between BPD and personality factors are reported. The participants in this study were 1073 individuals from 172 families of Mexican or Central American ancestry. Heritabilities and genetic correlations were calculated under a polygenic model using the maximum-likelihood method of obtaining variance components implemented in the SOLAR software package. Heritabilities of 0.49, 0.43, and 0.43 were found for the narrowest phenotype (schizoaffective bipolar and bipolar I), the intermediate phenotype (schizoaffective bipolar, bipolar I, and bipolar II), and the broadest phenotype (schizoaffective bipolar, bipolar I, bipolar II, and recurrent depression), respectively. For the Big Five personality factors, heritabilities were 0.25 for agreeableness, 0.24 for conscientiousness, 0.24 for extraversion, 0.23 for neuroticism, and 0.32 for openness to experience. For the narrowest phenotype, a significant negative correlation (-0.32) with extraversion was found. For the broadest phenotype, negative correlations were found for agreeableness (-0.35), conscientiousness (-0.39), and extraversion (-0.44). A positive correlation (0.37) was found with neuroticism. It is not possible to determine whether aspects of personality are factors in the development of bipolar disorder or vice versa. The short form of the NEO does not provide the ability to examine in detail which facets of extraversion are most closely related to bipolar disorder or to compare our results with studies that have used the long version of the scale. This study establishes a partial genetic basis for the Big Five personality factors in this set of families, while the environmental variances demonstrate that non-genetic factors are also important in their influence on

  7. Solid-state circuits

    CERN Document Server

    Pridham, G J

    2013-01-01

    Solid-State Circuits provides an introduction to the theory and practice underlying solid-state circuits, laying particular emphasis on field effect transistors and integrated circuits. Topics range from construction and characteristics of semiconductor devices to rectification and power supplies, low-frequency amplifiers, sine- and square-wave oscillators, and high-frequency effects and circuits. Black-box equivalent circuits of bipolar transistors, physical equivalent circuits of bipolar transistors, and equivalent circuits of field effect transistors are also covered. This volume is divided

  8. Nutrition and Bipolar Depression.

    Science.gov (United States)

    Beyer, John L; Payne, Martha E

    2016-03-01

    As with physical conditions, bipolar disorder is likely to be impacted by diet and nutrition. Patients with bipolar disorder have been noted to have relatively unhealthy diets, which may in part be the reason they also have an elevated risk of metabolic syndrome and obesity. An improvement in the quality of the diet should improve a bipolar patient's overall health risk profile, but it may also improve their psychiatric outcomes. New insights into biological dysfunctions that may be present in bipolar disorder have presented new theoretic frameworks for understanding the relationship between diet and bipolar disorder. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Superconducting transistor

    International Nuclear Information System (INIS)

    Gray, K.E.

    1978-01-01

    A three film superconducting tunneling device, analogous to a semiconductor transistor, is presented, including a theoretical description and experimental results showing a current gain of four. Much larger current gains are shown to be feasible. Such a development is particularly interesting because of its novelty and the striking analogies with the semiconductor junction transistor

  10. Silicon heterojunction transistor

    International Nuclear Information System (INIS)

    Matsushita, T.; Oh-uchi, N.; Hayashi, H.; Yamoto, H.

    1979-01-01

    SIPOS (Semi-insulating polycrystalline silicon) which is used as a surface passivation layer for highly reliable silicon devices constitutes a good heterojunction for silicon. P- or B-doped SIPOS has been used as the emitter material of a heterojunction transistor with the base and collector of silicon. An npn SIPOS-Si heterojunction transistor showing 50 times the current gain of an npn silicon homojunction transistor has been realized by high-temperature treatments in nitrogen and low-temperature annealing in hydrogen or forming gas

  11. Properties of Bipolar Fuzzy Hypergraphs

    OpenAIRE

    Akram, M.; Dudek, W. A.; Sarwar, S.

    2013-01-01

    In this article, we apply the concept of bipolar fuzzy sets to hypergraphs and investigate some properties of bipolar fuzzy hypergraphs. We introduce the notion of $A-$ tempered bipolar fuzzy hypergraphs and present some of their properties. We also present application examples of bipolar fuzzy hypergraphs.

  12. Bipolar Affective Disorder and Migraine

    Directory of Open Access Journals (Sweden)

    Birk Engmann

    2012-01-01

    Full Text Available This paper consists of a case history and an overview of the relationship, aetiology, and treatment of comorbid bipolar disorder migraine patients. A MEDLINE literature search was used. Terms for the search were bipolar disorder bipolar depression, mania, migraine, mood stabilizer. Bipolar disorder and migraine cooccur at a relatively high rate. Bipolar II patients seem to have a higher risk of comorbid migraine than bipolar I patients have. The literature on the common roots of migraine and bipolar disorder, including both genetic and neuropathological approaches, is broadly discussed. Moreover, bipolar disorder and migraine are often combined with a variety of other affective disorders, and, furthermore, behavioural factors also play a role in the origin and course of the diseases. Approach to treatment options is also difficult. Several papers point out possible remedies, for example, valproate, topiramate, which acts on both diseases, but no first-choice treatments have been agreed upon yet.

  13. Accelerating the life of transistors

    International Nuclear Information System (INIS)

    Qi Haochun; Lü Changzhi; Zhang Xiaoling; Xie Xuesong

    2013-01-01

    Choosing small and medium power switching transistors of the NPN type in a 3DK set as the study object, the test of accelerating life is conducted in constant temperature and humidity, and then the data are statistically analyzed with software developed by ourselves. According to degradations of such sensitive parameters as the reverse leakage current of transistors, the lifetime order of transistors is about more than 10 4 at 100 °C and 100% relative humidity (RH) conditions. By corrosion fracture of transistor outer leads and other failure modes, with the failure truncated testing, the average lifetime rank of transistors in different distributions is extrapolated about 10 3 . Failure mechanism analyses of degradation of electrical parameters, outer lead fracture and other reasons that affect transistor lifetime are conducted. The findings show that the impact of external stress of outer leads on transistor reliability is more serious than that of parameter degradation. (semiconductor devices)

  14. Gallium nitride at the millennial transition

    International Nuclear Information System (INIS)

    Pankovo, J.I.

    2000-01-01

    The properties of gallium nitride were uncovered in the early years of exploratory research and endowed with negative electron affinity that could be used to make efficient cold cathodes and even dynodes for electron multipliers. GaN has another property i.e. polar nature of the crystal which makes this material piezo-electric and has non-linear optical properties. The piezo-electric properties led to new piezo electric effect may cause interfacial charge. The non-uniform distribution of acceptors, there is also presence of threading and other dislocation in GaN. Defects reappear where two adjacent overgrowth merge, but the good lateral overgrow region is large enough to make lasers. Injection lasers benefit from strong electrical and optical environment. This was achieved by using quantum wells of InGaN in GaN and this can be doped with rare earth elements to exploit the atomic transition between core levels in these elements. The emission efficiency of electrically excited Er in GaN is nearly temperature incentive from 80K to room temperature. An other application of GaN is as a heterojunction emitter for a bi-polar transistor (HBT) that can operate at high temperatures. (A.B.)

  15. Bipolar Disorder in Children

    Science.gov (United States)

    2014-01-01

    Although bipolar disorder historically was thought to only occur rarely in children and adolescents, there has been a significant increase in children and adolescents who are receiving this diagnosis more recently (Carlson, 2005). Nonetheless, the applicability of the current bipolar disorder diagnostic criteria for children, particularly preschool children, remains unclear, even though much work has been focused on this area. As a result, more work needs to be done to further the understanding of bipolar symptoms in children. It is hoped that this paper can assist psychologists and other health service providers in gleaning a snapshot of the literature in this area so that they can gain an understanding of the diagnostic criteria and other behaviors that may be relevant and be informed about potential approaches for assessment and treatment with children who meet bipolar disorder criteria. First, the history of bipolar symptoms and current diagnostic criteria will be discussed. Next, assessment strategies that may prove helpful for identifying bipolar disorder will be discussed. Then, treatments that may have relevance to children and their families will be discussed. Finally, conclusions regarding work with children who may have a bipolar disorder diagnosis will be offered. PMID:24800202

  16. Cytokines in bipolar disorder

    DEFF Research Database (Denmark)

    Munkholm, Klaus; Vinberg, Maj; Vedel Kessing, Lars

    2012-01-01

    BACKGROUND: Current research and hypothesis regarding the pathophysiology of bipolar disorder suggests the involvement of immune system dysfunction that is possibly related to disease activity. Our objective was to systematically review evidence of cytokine alterations in bipolar disorder according...... to affective state. METHODS: We conducted a systemtic review of studies measuring endogenous cytokine concentrations in patients with bipolar disorder and a meta-analysis, reporting results according to the PRISMA statement. RESULTS: Thirteen studies were included, comprising 556 bipolar disorder patients...

  17. Abordagens psicoterápicas no transtorno bipolar Psychoterapeutic approach in bipolar disorder

    Directory of Open Access Journals (Sweden)

    Paulo Knapp

    2005-01-01

    Full Text Available Embora o tratamento farmacológico seja essencial para o tratamento do transtorno bipolar, apenas 40% de todos os pacientes que aderem às medicações permanecem assintomáticos durante o período de seguimento, o que tem levado ao desenvolvimento de intervenções psicoterápicas associadas. O objetivo deste artigo é examinar as evidências atuais da eficácia de intervenções psicoterápicas no tratamento do transtorno bipolar. Foi realizada uma pesquisa bibliográfica por meio do MedLine, PsychoINFO, Lilacs e Cochrane Data Bank, até o ano de 2004, em que foram procurados artigos originais e revisões sobre as abordagens psicoterápicas utilizadas no tratamento do transtorno bipolar. Há várias abordagens que podem se mostrar úteis no tratamento do transtorno bipolar. A psicoeducação e a terapia cognitivo-comportamental apresentam as evidências mais consistentes e são as técnicas mais amplamente estudadas. As intervenções envolvendo familiares e a terapia interpessoal e de ritmo social se mostram tratamentos eficazes em determinadas situações. Há alguns estudos empregando a terapia psicodinâmica no transtorno bipolar, mas são estudos com limitações metodológicas. Apesar de haver evidências demonstrando a eficácia de determinadas abordagens psicoterápicas no transtorno bipolar, ainda é necessária a realização de estudos posteriores que comprovem tais dados e que desenvolvam tratamentos baseados em modelos etiológicos e que identifiquem tratamentos específicos para as diferentes fases e tipos de transtorno bipolar.Although pharmacological treatment is essential for treating bipolar disorder, less than half of all medication compliant patients are non-symptomatic during follow-up, which has led to developments of adjunctive psychosocial interventions. This paper examines the current evidence for effectiveness of psychotherapeutic interventions in the treatment of bipolar disorder. Searches were undertaken through Med

  18. Temperature characteristics research of SOI pressure sensor based on asymmetric base region transistor

    Science.gov (United States)

    Zhao, Xiaofeng; Li, Dandan; Yu, Yang; Wen, Dianzhong

    2017-07-01

    Based on the asymmetric base region transistor, a pressure sensor with temperature compensation circuit is proposed in this paper. The pressure sensitive structure of the proposed sensor is constructed by a C-type silicon cup and a Wheatstone bridge with four piezoresistors ({R}1, {R}2, {R}3 and {R}4) locating on the edge of a square silicon membrane. The chip was designed and fabricated on a silicon on insulator (SOI) wafer by micro electromechanical system (MEMS) technology and bipolar transistor process. When the supply voltage is 5.0 V, the corresponding temperature coefficient of the sensitivity (TCS) for the sensor before and after temperature compensation are -1862 and -1067 ppm/°C, respectively. Through varying the ratio of the base region resistances {r}1 and {r}2, the TCS for the sensor with the compensation circuit is -127 ppm/°C. It is possible to use this compensation circuit to improve the temperature characteristics of the pressure sensor. Project supported by the National Natural Science Foundation of China (No. 61471159), the Natural Science Foundation of Heilongjiang Province (No. F201433), the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province (No. 2015018), and the Special Funds for Science and Technology Innovation Talents of Harbin in China (No. 2016RAXXJ016).

  19. ON BIPOLAR SINGLE VALUED NEUTROSOPHIC GRAPHS

    OpenAIRE

    Said Broumi; Mohamed Talea; Assia Bakali; Florentin Smarandache

    2016-01-01

    In this article, we combine the concept of bipolar neutrosophic set and graph theory. We introduce the notions of bipolar single valued neutrosophic graphs, strong bipolar single valued neutrosophic graphs, complete bipolar single valued neutrosophic graphs, regular bipolar single valued neutrosophic graphs and investigate some of their related properties.

  20. Systematic review of the prevalence of bipolar disorder and bipolar spectrum disorders in population-based studies

    Directory of Open Access Journals (Sweden)

    José Caetano Dell'Aglio Jr.

    2013-01-01

    Full Text Available This paper describes the findings of a systematic literature review aimed at providing an overview of the lifetime prevalence of bipolar disorder and bipolar spectrum disorders in population-based studies. Databases MEDLINE, ProQuest, Psychnet, and Web of Science were browsed for papers published in English between 1999 and May 2012 using the following search string: bipolar disorders OR bipolar spectrum disorders AND prevalence OR cross-sectional OR epidemiology AND population-based OR non-clinical OR community based. The search yielded a total of 434 papers, but only those published in peer-reviewed journals and with samples aged ≥ 18 years were included, resulting in a final sample of 18 papers. Results revealed rather heterogeneous findings concerning the prevalence of bipolar disorders and bipolar spectrum disorders. Lifetime prevalence of bipolar disorder ranged from 0.1 to 7.5%, whereas lifetime prevalence of bipolar spectrum disorders ranged from 2.4 to 15.1%. Differences in the rates of bipolar disorder and bipolar spectrum disorders may be related to the consideration of subthreshold criteria upon diagnosis. Differences in the prevalence of different subtypes of the disorder are discussed in light of diagnostic criteria and instruments applied.

  1. Scientific attitudes towards bipolar disorders

    Directory of Open Access Journals (Sweden)

    Mohammad-Hossein Biglu

    2014-02-01

    Full Text Available Introduction: Bipolar disorder is a psychiatric condition that is also called manic-depressive disease. It causes unusual changes in mood, energy, activity levels, and the ability to carry out day-to-day tasks. In the present study, 3 sets of data were considered and analyzed: first, all papers categorized under Bipolar Disorders in Science Citation Index Expanded (SCI-E database through 2001-2011; second, papers published by the international journal of Bipolar Disorders indexed in SCI-E during a period of 11 years; and third, all papers distributed by the international journal of Bipolar Disorders indexed in MEDLINE during the period of study. Methods: The SCI-E database was used to extract all papers indexed with the topic of Bipolar Disorders as well as all papers published by The International Journal of Bipolar Disorders. Extraction of data from MEDLINE was restricted to the journals name from setting menu. The Science of Science Tool was used to map the co-authorship network of papers published by The International Journal of Bipolar Disorders through 2009-2011. Results: Analysis of data showed that the majority of publications in the subject area of bipolar disorders indexed in SCI-E were published by The International Journal of Bipolar Disorders. Although journal articles consisted of 59% of the total publication type in SCI-E, 65% of publications distributed by The Journal of Bipolar Disorders were in the form of meetingabstracts. Journal articles consisted of only 23% of the total publications. USA was the leading country regarding sharing data in the field of bipolar disorders followed by England, Canada, and Germany. Conclusion: The editorial policy of The International Journal of Bipolar Disorders has been focused on new themes and new ways of researching in the subject area of bipolar disorder. Regarding the selection of papers for indexing, the SCI-E database selects data more comprehensively than MEDLINE. The number of papers

  2. High-performance vertical organic transistors.

    Science.gov (United States)

    Kleemann, Hans; Günther, Alrun A; Leo, Karl; Lüssem, Björn

    2013-11-11

    Vertical organic thin-film transistors (VOTFTs) are promising devices to overcome the transconductance and cut-off frequency restrictions of horizontal organic thin-film transistors. The basic physical mechanisms of VOTFT operation, however, are not well understood and VOTFTs often require complex patterning techniques using self-assembly processes which impedes a future large-area production. In this contribution, high-performance vertical organic transistors comprising pentacene for p-type operation and C60 for n-type operation are presented. The static current-voltage behavior as well as the fundamental scaling laws of such transistors are studied, disclosing a remarkable transistor operation with a behavior limited by injection of charge carriers. The transistors are manufactured by photolithography, in contrast to other VOTFT concepts using self-assembled source electrodes. Fluorinated photoresist and solvent compounds allow for photolithographical patterning directly and strongly onto the organic materials, simplifying the fabrication protocol and making VOTFTs a prospective candidate for future high-performance applications of organic transistors. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. stability analysis of a three-phase solid-state var compensator

    African Journals Online (AJOL)

    2012-11-03

    Nov 3, 2012 ... solid-state devices (bipolar junction transistor (BJT), insulated-gate bipolar transistor (IGBT), gate-turn- off thyristor (GTO) and power MOSFET has elim- inated these problems. The voltage source inverter. (VSI) employing any one of these devices is an efficient equipment for reactive power compensation or ...

  4. Bipolar Disorder.

    Science.gov (United States)

    Spearing, Melissa

    Bipolar disorder, a brain disorder that causes unusual shifts in a person's mood, affects approximately one percent of the population. It commonly occurs in late adolescence and is often unrecognized. The diagnosis of bipolar disorder is made on the basis of symptoms, course of illness, and when possible, family history. Thoughts of suicide are…

  5. Silicon nanowire transistors

    CERN Document Server

    Bindal, Ahmet

    2016-01-01

    This book describes the n and p-channel Silicon Nanowire Transistor (SNT) designs with single and dual-work functions, emphasizing low static and dynamic power consumption. The authors describe a process flow for fabrication and generate SPICE models for building various digital and analog circuits. These include an SRAM, a baseband spread spectrum transmitter, a neuron cell and a Field Programmable Gate Array (FPGA) platform in the digital domain, as well as high bandwidth single-stage and operational amplifiers, RF communication circuits in the analog domain, in order to show this technology’s true potential for the next generation VLSI. Describes Silicon Nanowire (SNW) Transistors, as vertically constructed MOS n and p-channel transistors, with low static and dynamic power consumption and small layout footprint; Targets System-on-Chip (SoC) design, supporting very high transistor count (ULSI), minimal power consumption requiring inexpensive substrates for packaging; Enables fabrication of different types...

  6. Logarithmic current-measuring transistor circuits

    DEFF Research Database (Denmark)

    Højberg, Kristian Søe

    1967-01-01

    Describes two transistorized circuits for the logarithmic measurement of small currents suitable for nuclear reactor instrumentation. The logarithmic element is applied in the feedback path of an amplifier, and only one dual transistor is used as logarithmic diode and temperature compensating...... transistor. A simple one-amplifier circuit is compared with a two-amplifier system. The circuits presented have been developed in connexion with an amplifier using a dual m.o.s. transistor input stage with diode-protected gates....

  7. Thwarted interpersonal needs and suicide ideation: Comparing psychiatric inpatients with bipolar and non-bipolar mood disorders.

    Science.gov (United States)

    Taylor, Nathanael J; Mitchell, Sean M; Roush, Jared F; Brown, Sarah L; Jahn, Danielle R; Cukrowicz, Kelly C

    2016-12-30

    Psychiatric inpatients are at heightened risk for suicide, and evidence suggests that psychiatric inpatients with bipolar mood disorders may be at greater risk for suicide ideation compared to those with non-bipolar mood disorders. There is a paucity of research directly comparing risk factors for suicide ideation in bipolar versus non-bipolar mood disorders in an inpatient sample. The current study sought to clarify the association between two constructs from the interpersonal theory of suicide (i.e., perceived burdensomeness and thwarted belongingness) in leading to suicide ideation among psychiatric inpatients with bipolar and non-bipolar mood disorders. Participants were (N=90) psychiatric inpatients with a bipolar (n = 20) or non-bipolar mood disorder (n=70; per their medical charts). Perceived burdensomeness, but not thwarted belongingness, was significantly associated with suicide ideation after adjusting for other covariates. This suggests perceived burdensomeness may play a key role in suicide ideation among psychiatric inpatients with any mood disorder and highlights the importance of assessment and intervention of perceived burdensomeness in this population. Contrary to our hypothesis, mood disorder group (i.e., bipolar versus non-bipolar) did not moderate the relations between perceived burdensomeness/thwarted belongingness and suicide ideation. Published by Elsevier Ireland Ltd.

  8. Bipolar polygenic loading and bipolar spectrum features in major depressive disorder

    Science.gov (United States)

    Wiste, Anna; Robinson, Elise B; Milaneschi, Yuri; Meier, Sandra; Ripke, Stephan; Clements, Caitlin C; Fitzmaurice, Garrett M; Rietschel, Marcella; Penninx, Brenda W; Smoller, Jordan W; Perlis, Roy H

    2014-01-01

    Objectives Family and genetic studies indicate overlapping liability for major depressive disorder and bipolar disorder. The purpose of this study was to determine whether this shared genetic liability influences clinical presentation. Methods A polygenic risk score for bipolar disorder, derived from a large genome-wide association meta-analysis, was generated for each subject of European–American ancestry (n = 1,274) in the Sequential Treatment Alternatives to Relieve Depression study (STAR*D) outpatient major depressive disorder cohort. A hypothesis-driven approach was used to test for association between bipolar disorder risk score and features of depression associated with bipolar disorder in the literature. Follow-up analyses were performed in two additional cohorts. Results A generalized linear mixed model including seven features hypothesized to be associated with bipolar spectrum illness was significantly associated with bipolar polygenic risk score [F = 2.07, degrees of freedom (df) = 7, p = 0.04). Features included early onset, suicide attempt, recurrent depression, atypical depression, subclinical mania, subclinical psychosis, and severity. Post-hoc univariate analyses demonstrated that the major contributors to this omnibus association were onset of illness at age ≤ 18 years [odds ratio (OR) = 1.2, p = 0.003], history of suicide attempt (OR = 1.21, p = 0.03), and presence of at least one manic symptom (OR = 1.16, p = 0.02). The maximal variance in these traits explained by polygenic score ranged from 0.8–1.1%. However, analyses in two replication cohorts testing a five feature model did not support this association. Conclusions Bipolar genetic loading appeared to be associated with bipolar-like presentation in major depressive disorder in the primary analysis. However, results are at most inconclusive because of lack of replication. Replication efforts are challenged by different ascertainment and assessment strategies in the different cohorts

  9. A High-Voltage Level Tolerant Transistor Circuit

    NARCIS (Netherlands)

    Annema, Anne J.; Geelen, Godefridus Johannes Gertrudis Maria

    2001-01-01

    A high-voltage level tolerant transistor circuit, comprising a plurality of cascoded transistors, including a first transistor (T1) operatively connected to a high-voltage level node (3) and a second transistor (T2) operatively connected to a low-voltage level node (2). The first transistor (T1)

  10. Genetics Home Reference: bipolar disorder

    Science.gov (United States)

    ... Email Facebook Twitter Home Health Conditions Bipolar disorder Bipolar disorder Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Bipolar disorder is a mental health condition that causes extreme ...

  11. Vertical organic transistors

    International Nuclear Information System (INIS)

    Lüssem, Björn; Günther, Alrun; Fischer, Axel; Kasemann, Daniel; Leo, Karl

    2015-01-01

    Organic switching devices such as field effect transistors (OFETs) are a key element of future flexible electronic devices. So far, however, a commercial breakthrough has not been achieved because these devices usually lack in switching speed (e.g. for logic applications) and current density (e.g. for display pixel driving). The limited performance is caused by a combination of comparatively low charge carrier mobilities and the large channel length caused by the need for low-cost structuring. Vertical Organic Transistors are a novel technology that has the potential to overcome these limitations of OFETs. Vertical Organic Transistors allow to scale the channel length of organic transistors into the 100 nm regime without cost intensive structuring techniques. Several different approaches have been proposed in literature, which show high output currents, low operation voltages, and comparatively high speed even without sub-μm structuring technologies. In this review, these different approaches are compared and recent progress is highlighted. (topical review)

  12. Vertical organic transistors.

    Science.gov (United States)

    Lüssem, Björn; Günther, Alrun; Fischer, Axel; Kasemann, Daniel; Leo, Karl

    2015-11-11

    Organic switching devices such as field effect transistors (OFETs) are a key element of future flexible electronic devices. So far, however, a commercial breakthrough has not been achieved because these devices usually lack in switching speed (e.g. for logic applications) and current density (e.g. for display pixel driving). The limited performance is caused by a combination of comparatively low charge carrier mobilities and the large channel length caused by the need for low-cost structuring. Vertical Organic Transistors are a novel technology that has the potential to overcome these limitations of OFETs. Vertical Organic Transistors allow to scale the channel length of organic transistors into the 100 nm regime without cost intensive structuring techniques. Several different approaches have been proposed in literature, which show high output currents, low operation voltages, and comparatively high speed even without sub-μm structuring technologies. In this review, these different approaches are compared and recent progress is highlighted.

  13. On theory of single-molecule transistor

    International Nuclear Information System (INIS)

    Tran Tien Phuc

    2009-01-01

    The results of the study on single-molecule transistor are mainly investigated in this paper. The structure of constructed single-molecule transistor is similar to a conventional MOSFET. The conductive channel of the transistors is a single-molecule of halogenated benzene derivatives. The chemical simulation software CAChe was used to design and implement for the essential parameter of the molecules utilized as the conductive channel. The GUI of Matlab has been built to design its graphical interface, calculate and plot the output I-V characteristic curves for the transistor. The influence of temperature, length and width of the conductive channel, and gate voltage is considered. As a result, the simulated curves are similar to the traditional MOSFET's. The operating temperature range of the transistors is wider compared with silicon semiconductors. The supply voltage for transistors is only about 1 V. The size of transistors in this research is several nanometers.

  14. Life expectancy in bipolar disorder

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Vradi, Eleni; Andersen, Per Kragh

    2015-01-01

    OBJECTIVE: Life expectancy in patients with bipolar disorder has been reported to be decreased by 11 to 20 years. These calculations are based on data for individuals at the age of 15 years. However, this may be misleading for patients with bipolar disorder in general as most patients have a later...... onset of illness. The aim of the present study was to calculate the remaining life expectancy for patients of different ages with a diagnosis of bipolar disorder. METHODS: Using nationwide registers of all inpatient and outpatient contacts to all psychiatric hospitals in Denmark from 1970 to 2012 we...... remaining life expectancy in bipolar disorder and that of the general population decreased with age, indicating that patients with bipolar disorder start losing life-years during early and mid-adulthood. CONCLUSIONS: Life expectancy in bipolar disorder is decreased substantially, but less so than previously...

  15. Experimental synchronization of chaos in a large ring of mutually coupled single-transistor oscillators: Phase, amplitude, and clustering effects

    Energy Technology Data Exchange (ETDEWEB)

    Minati, Ludovico, E-mail: lminati@ieee.org, E-mail: ludovico.minati@unitn.it [MR-Lab, Center for Mind/Brain Science, University of Trento, Italy and Scientific Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan (Italy)

    2014-12-01

    In this paper, experimental evidence of multiple synchronization phenomena in a large (n = 30) ring of chaotic oscillators is presented. Each node consists of an elementary circuit, generating spikes of irregular amplitude and comprising one bipolar junction transistor, one capacitor, two inductors, and one biasing resistor. The nodes are mutually coupled to their neighbours via additional variable resistors. As coupling resistance is decreased, phase synchronization followed by complete synchronization is observed, and onset of synchronization is associated with partial synchronization, i.e., emergence of communities (clusters). While component tolerances affect community structure, the general synchronization properties are maintained across three prototypes and in numerical simulations. The clusters are destroyed by adding long distance connections with distant notes, but are otherwise relatively stable with respect to structural connectivity changes. The study provides evidence that several fundamental synchronization phenomena can be reliably observed in a network of elementary single-transistor oscillators, demonstrating their generative potential and opening way to potential applications of this undemanding setup in experimental modelling of the relationship between network structure, synchronization, and dynamical properties.

  16. Experimental synchronization of chaos in a large ring of mutually coupled single-transistor oscillators: Phase, amplitude, and clustering effects

    International Nuclear Information System (INIS)

    Minati, Ludovico

    2014-01-01

    In this paper, experimental evidence of multiple synchronization phenomena in a large (n = 30) ring of chaotic oscillators is presented. Each node consists of an elementary circuit, generating spikes of irregular amplitude and comprising one bipolar junction transistor, one capacitor, two inductors, and one biasing resistor. The nodes are mutually coupled to their neighbours via additional variable resistors. As coupling resistance is decreased, phase synchronization followed by complete synchronization is observed, and onset of synchronization is associated with partial synchronization, i.e., emergence of communities (clusters). While component tolerances affect community structure, the general synchronization properties are maintained across three prototypes and in numerical simulations. The clusters are destroyed by adding long distance connections with distant notes, but are otherwise relatively stable with respect to structural connectivity changes. The study provides evidence that several fundamental synchronization phenomena can be reliably observed in a network of elementary single-transistor oscillators, demonstrating their generative potential and opening way to potential applications of this undemanding setup in experimental modelling of the relationship between network structure, synchronization, and dynamical properties

  17. Bipolar Disorder in Women

    Directory of Open Access Journals (Sweden)

    Sermin Kesebir

    2013-06-01

    Full Text Available The research on gender's role in bipolar disorders has drawn significant interest recently. The presentation and course of bipolar disorder differs between women and men. Women experience depressive episodes, dysphoric mood, mixed states, rapid cycling and seasonal patterns more often than men. Comorbidity, particularly thyroid disease, migraine, obesity, and anxiety disorders laso occur more frequently in women than men. On the other hand men with bipolar disorder are also more likely than women to have problems with drug or alcohol abuse. The pregnancy and postpartum period is a time of high risk for onset and recurrence of bipolar disorder in women.

  18. Dosimetric properties of MOS transistors

    International Nuclear Information System (INIS)

    Frank, H.; Petr, I.

    1977-01-01

    The structure of MOS transistors is described and their characteristics given. The experiments performed and data in the literature show the following dosimetric properties of MOS transistors: while for low gamma doses the transistor response to exposure is linear, it shows saturation for higher doses (exceeding 10 3 Gy in tissue). The response is independent of the energy of radiation and of the dose rate (within 10 -2 to 10 5 Gy/s). The spontaneous reduction with time of the spatial charge captured by the oxide layer (fading) is small and acceptable from the point of view of dosimetry. Curves are given of isochronous annealing of the transistors following irradiation with 137 Cs and 18 MeV electrons for different voltages during irradiation. The curves show that in MOS transistors irradiated with high-energy electrons the effect of annealing is less than in transistors irradiated with 137 Cs. In view of the requirement of using higher temperatures (approx. 400 degC) for the complete ''erasing'' of the captured charge, unsealed systems must be used for dosimetric purposes. The effect was also studied of neutron radiation, proton radiation and electron radiation on the MOS transistor structure. For MOS transistor irradiation with 14 MeV neutrons from a neutron generator the response was 4% of that for gamma radiation at the same dose equivalent. The effect of proton radiation was studied as related to the changes in MOS transistor structure during space flights. The response curve shapes are similar to those of gamma radiation curves. The effect of electron radiation on the MOS structure was studied by many authors. The experiments show that for each thickness of the SiO 2 layer an electron energy exists at which the size of the charge captured in SiO 2 is the greatest. All data show that MOS transistors are promising for radiation dosimetry. The main advantage of MOS transistors as gamma dosemeters is the ease and speed of evaluation, low sensitivity to neutron

  19. Colour tuneable light-emitting transistor

    Energy Technology Data Exchange (ETDEWEB)

    Feldmeier, Eva J.; Melzer, Christian; Seggern, Heinz von [Electronic Materials Department, Institute of Materials Science, Technische Universitaet Darmstadt (Germany)

    2010-07-01

    In recent years the interest in ambipolar organic light-emitting field-effect transistors has increased steadily as the devices combine switching behaviour of transistors with light emission. Usually, small molecules and polymers with a band gap in the visible spectral range serve as semiconducting materials. Mandatory remain balanced injection and transport properties for both charge carrier types to provide full control of the spatial position of the recombination zone of electrons and holes in the transistor channel via the applied voltages. As will be presented here, the spatial control of the recombination zone opens new possibilities towards light-emitting devices with colour tuneable emission. In our contribution an organic light-emitting field-effect transistors is presented whose emission colour can be changed by the applied voltages. The organic top-contact field-effect transistor is based on a parallel layer stack of acenes serving as organic transport and emission layers. The transistor displays ambipolar characteristics with a narrow recombination zone within the transistor channel. During operation the recombination zone can be moved by a proper change in the drain and gate bias from one organic semiconductor layer to another one inducing a change in the emission colour. In the presented example the emission maxima can be switched from 530 nm to 580 nm.

  20. Bipolar polygenic loading and bipolar spectrum features in major depressive disorder

    NARCIS (Netherlands)

    Wiste, Anna; Robinson, Elise B.; Milaneschi, Yuri; Meier, Sandra; Ripke, Stephan; Clements, Caitlin C.; Fitzmaurice, Garrett M.; Rietschel, Marcella; Penninx, Brenda W.; Smoller, Jordan W.; Perlis, Roy H.

    Objectives Family and genetic studies indicate overlapping liability for major depressive disorder and bipolar disorder. The purpose of the present study was to determine whether this shared genetic liability influences clinical presentation. Methods A polygenic risk score for bipolar disorder,

  1. Dosimetric properties of MOS transistors

    International Nuclear Information System (INIS)

    Peter, I.; Frank, G.

    1977-01-01

    The performance of MOS transistors as gamma detectors has been tested. The dosimeter sensitivity has proved to be independent on the doses ranging from 10 3 to 10 6 R, and gamma energy of 137 Cs, 60 Co - sources and 5 - 18 MeV electrons. Fading of the space charge trapped by the SiO 2 layer of the transistor has appeared to be neglegible at room temperature after 400 hrs. The isochronous annealing in the temperature range of 40-260 deg C had a more substantial effect on the space charge of the transistor irradiated with 18 MeV electrons than on the 137 Cs gamma-irradiated transistors. This proved a repeated use of γ-dosemeters. MOS transistors are concluded to be promising for gamma dosimetry [ru

  2. Early Intervention in Bipolar Disorder.

    Science.gov (United States)

    Vieta, Eduard; Salagre, Estela; Grande, Iria; Carvalho, André F; Fernandes, Brisa S; Berk, Michael; Birmaher, Boris; Tohen, Mauricio; Suppes, Trisha

    2018-05-01

    Bipolar disorder is a recurrent disorder that affects more than 1% of the world population and usually has its onset during youth. Its chronic course is associated with high rates of morbidity and mortality, making bipolar disorder one of the main causes of disability among young and working-age people. The implementation of early intervention strategies may help to change the outcome of the illness and avert potentially irreversible harm to patients with bipolar disorder, as early phases may be more responsive to treatment and may need less aggressive therapies. Early intervention in bipolar disorder is gaining momentum. Current evidence emerging from longitudinal studies indicates that parental early-onset bipolar disorder is the most consistent risk factor for bipolar disorder. Longitudinal studies also indicate that a full-blown manic episode is often preceded by a variety of prodromal symptoms, particularly subsyndromal manic symptoms, therefore supporting the existence of an at-risk state in bipolar disorder that could be targeted through early intervention. There are also identifiable risk factors that influence the course of bipolar disorder, some of them potentially modifiable. Valid biomarkers or diagnosis tools to help clinicians identify individuals at high risk of conversion to bipolar disorder are still lacking, although there are some promising early results. Pending more solid evidence on the best treatment strategy in early phases of bipolar disorder, physicians should carefully weigh the risks and benefits of each intervention. Further studies will provide the evidence needed to finish shaping the concept of early intervention. AJP AT 175 Remembering Our Past As We Envision Our Future April 1925: Interpretations of Manic-Depressive Phases Earl Bond and G.E. Partridge reviewed a number of patients with manic-depressive illness in search of a unifying endo-psychic conflict. They concluded that understanding either phase of illness was "elusive" and

  3. Virginia Woolf, neuroprogression, and bipolar disorder

    Directory of Open Access Journals (Sweden)

    Manuela V. Boeira

    2016-01-01

    Full Text Available Family history and traumatic experiences are factors linked to bipolar disorder. It is known that the lifetime risk of bipolar disorder in relatives of a bipolar proband are 5-10% for first degree relatives and 40-70% for monozygotic co-twins. It is also known that patients with early childhood trauma present earlier onset of bipolar disorder, increased number of manic episodes, and more suicide attempts. We have recently reported that childhood trauma partly mediates the effect of family history on bipolar disorder diagnosis. In light of these findings from the scientific literature, we reviewed the work of British writer Virginia Woolf, who allegedly suffered from bipolar disorder. Her disorder was strongly related to her family background. Moreover, Virginia Woolf was sexually molested by her half siblings for nine years. Her bipolar disorder symptoms presented a pernicious course, associated with hospitalizations, suicidal behavioral, and functional impairment. The concept of neuroprogression has been used to explain the clinical deterioration that takes places in a subgroup of bipolar disorder patients. The examination of Virgina Woolf’s biography and art can provide clinicians with important insights about the course of bipolar disorder.

  4. Epidemiology in Pediatric Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Caner Mutlu

    2015-12-01

    Full Text Available Childhood and adolescent bipolar disorder diagnosis has been increasing recently. Since studies evaluating attempted suicide rates in children and adolescents have shown bipolarity to be a significant risk factor, diagnosis and treatment of bipolarity has become a very important issue. Since there is a lack of specific diagnostic criteria for especially preadolescent samples and evaluations are made mostly symptomatically, suspicions about false true diagnosis and increased prevalence rates have emerged. This situation leads to controversial data about the prevalence rates of bipolar disorder in children and adolescents. The aim of this article is to review the prevalence of childhood and adolescent bipolar disorder in community, inpatient and outpatient based samples in literature.

  5. BIPOLAR DISORDER: A REVIEW

    OpenAIRE

    Pathan Dilnawaz N; Ziyaurrahaman A.R; Bhise K.S.

    2010-01-01

    Bipolar disorder (BD) is a severe psychiatric disorder that results in poor global functioning, reduced quality of life and high relapse rates. Research finds that many adults with bipolar disorder identify the onset of symptoms in childhood and adolescence, indicating the importance of early accurate diagnosis and treatment. Accurate diagnosis of mood disorders is critical for treatment to be effective. Distinguishing between major depression and bipolar disorders, especially the depressed p...

  6. Transistor-based particle detection systems and methods

    Science.gov (United States)

    Jain, Ankit; Nair, Pradeep R.; Alam, Muhammad Ashraful

    2015-06-09

    Transistor-based particle detection systems and methods may be configured to detect charged and non-charged particles. Such systems may include a supporting structure contacting a gate of a transistor and separating the gate from a dielectric of the transistor, and the transistor may have a near pull-in bias and a sub-threshold region bias to facilitate particle detection. The transistor may be configured to change current flow through the transistor in response to a change in stiffness of the gate caused by securing of a particle to the gate, and the transistor-based particle detection system may configured to detect the non-charged particle at least from the change in current flow.

  7. Electron irradiation of power transistors

    International Nuclear Information System (INIS)

    Hower, P.L.; Fiedor, R.J.

    1982-01-01

    A method for reducing storage time and gain parameters in a semiconductor transistor includes the step of subjecting the transistor to electron irradiation of a dosage determined from measurements of the parameters of a test batch of transistors. Reduction of carrier lifetime by proton bombardment and gold doping is mentioned as an alternative to electron irradiation. (author)

  8. The point of practical use for the transistor circuit

    International Nuclear Information System (INIS)

    1996-01-01

    This is comprised of eight chapters and goes as follows; what is transistor? the first step for use of transistor such as connection between power and signal source, static characteristic of transistor and equivalent circuit of transistor, design of easy small-signal amplifier circuit, design for amplification of electric power and countermeasure for prevention of trouble, transistor concerned interface, transistor circuit around micro computer, transistor in active use of FET and power circuit and transistor. It has an appendix on transistor and design of bias of FET circuits like small signal transistor circuit and FET circuit.

  9. Silicon on insulator self-aligned transistors

    Science.gov (United States)

    McCarthy, Anthony M.

    2003-11-18

    A method for fabricating thin-film single-crystal silicon-on-insulator (SOI) self-aligned transistors. Standard processing of silicon substrates is used to fabricate the transistors. Physical spaces, between the source and gate, and the drain and gate, introduced by etching the polysilicon gate material, are used to provide connecting implants (bridges) which allow the transistor to perform normally. After completion of the silicon substrate processing, the silicon wafer is bonded to an insulator (glass) substrate, and the silicon substrate is removed leaving the transistors on the insulator (glass) substrate. Transistors fabricated by this method may be utilized, for example, in flat panel displays, etc.

  10. Physical limits of silicon transistors and circuits

    International Nuclear Information System (INIS)

    Keyes, Robert W

    2005-01-01

    A discussion on transistors and electronic computing including some history introduces semiconductor devices and the motivation for miniaturization of transistors. The changing physics of field-effect transistors and ways to mitigate the deterioration in performance caused by the changes follows. The limits of transistors are tied to the requirements of the chips that carry them and the difficulties of fabricating very small structures. Some concluding remarks about transistors and limits are presented

  11. Bipolar Disorder and Cancer

    Directory of Open Access Journals (Sweden)

    Sermin Kesebir

    2012-06-01

    Full Text Available Prevalence studies and studies on causation relations have shown that the relation between psychiatric disorders and chronic physical diseases is neglected. For heterogeneous diseases an increasing number of susceptibility variants are being defined. Alzheimer disease, bipolar disorder, breast and prostate cancer, coronary artery disease, Chron's disease, systemic lupus eritematosus, type 1 and type 2 diabetes mellitus are mentioned together with epigenetic concept. In acrocentric zone of chromosome 13, breast cancer, retinoblastoma, chronic Iymphocytic leukemia genes with B cells, dopamin loci of bipolar disorder are found together. Among bipolar and healthy individuals, an increase risk of breast cancer in female cases has been resported. On the other hand, psychosocial factors that affect stress and response to stress itself may be important variables in prognosis and progression of different cancer types. During the course of many cancer types –especially brain tumors- and during treatment of chemotherapeutic agents, bipolar symptomatology may appear. In this article, it is reviewed with relevant literature that whether an etiological relation between bipolar disorder and cancer exist and how both diseases affect each other's course and treatment.

  12. Six years of evidence-based adult dissection tonsillectomy with ultrasonic scalpel, bipolar electrocautery, bipolar radiofrequency or 'cold steel' dissection.

    Science.gov (United States)

    Ragab, S M

    2012-10-01

    To conduct an adequately powered, prospective, randomised, controlled trial comparing adult dissection tonsillectomy using either ultrasonic scalpel, bipolar electrocautery, bipolar radiofrequency or 'cold steel' dissection. Three hundred patients were randomised into four tonsillectomy technique groups. The operative time, intra-operative bleeding, post-operative pain, tonsillar fossa healing, return to full diet, return to work and post-operative complications were recorded. The bipolar radiofrequency group had a shorter mean operative time. The mean intra-operative blood loss during bipolar radiofrequency tonsillectomy was significantly less compared with cold dissection and ultrasonic scalpel tonsillectomy. Pain scores were significantly higher after bipolar electrocautery tonsillectomy. Patients undergoing bipolar electrocautery tonsillectomy required significantly more days to return to full diet and work. The bipolar electrocautery group showed significantly reduced tonsillar fossa healing during the first and second post-operative weeks. In this adult series, bipolar radiofrequency tonsillectomy was superior to ultrasonic, bipolar electrocautery and cold dissection tonsillectomies. This method combines the advantages of 'hot' and 'cold' tonsillectomy.

  13. Course of Subthreshold Bipolar Disorder in Youth: Diagnostic Progression from Bipolar Disorder Not Otherwise Specified

    Science.gov (United States)

    Axelson, David A.; Birmaher, Boris; Strober, Michael A.; Goldstein, Benjamin I.; Ha, Wonho; Gill, Mary Kay; Goldstein, Tina R.; Yen, Shirley; Hower, Heather; Hunt, Jeffrey I.; Liao, Fangzi; Iyengar, Satish; Dickstein, Daniel; Kim, Eunice; Ryan, Neal D.; Frankel, Erica; Keller, Martin B.

    2011-01-01

    Objective: To determine the rate of diagnostic conversion from an operationalized diagnosis of bipolar disorder not otherwise specified (BP-NOS) to bipolar I disorder (BP-I) or bipolar II disorder (BP-II) in youth over prospective follow-up and to identify factors associated with conversion. Method: Subjects were 140 children and adolescents…

  14. The Integration and Applications of Organic Thin Film Transistors and Ferroelectric Polymers

    Science.gov (United States)

    Hsu, Yu-Jen

    Organic thin film transistors and ferroelectric polymer (polyvinylidene difluoride) sheet material are integrated to form various sensors for stress/strain, acoustic wave, and Infrared (heat) sensing applications. Different from silicon-based transistors, organic thin film transistors can be fabricated and processed in room-temperature and integrated with a variety of substrates. On the other hand, polyvinylidene difluoride (PVDF) exhibits ferroelectric properties that are highly useful for sensor applications. The wide frequency bandwidth (0.001 Hz to 10 GHz), vast dynamic range (100n to 10M psi), and high elastic compliance (up to 3 percent) make PVDF a more suitable candidate over ceramic piezoelectric materials for thin and flexible sensor applications. However, the low Curie temperature may have impeded its integration with silicon technology. Organic thin film transistors, however, do not have the limitation of processing temperature, hence can serve as transimpedance amplifiers to convert the charge signal generated by PVDF into current signal that are more measurable and less affected by any downstream parasitics. Piezoelectric sensors are useful for a range of applications, but passive arrays suffer from crosstalk and signal attenuation which have complicated the development of array-based PVDF sensors. We have used organic field effect transistors, which are compatible with the low Curie temperature of a flexible piezoelectric polymer,PVDF, to monolithically fabricate transimpedance amplifiers directly on the sensor surface and convert the piezoelectric charge signal into a current signal which can be detected even in the presence of parasitic capacitances. The device couples the voltage generated by the PVDF film under strain into the gate of the organic thin film transistors (OFET) using an arrangement that allows the full piezoelectric voltage to couple to the channel, while also increasing the charge retention time. A bipolar detector is created by

  15. Multichannel monolithic front-end system design. Part II. Microwave bipolar-JFET process for low-noise charge-sensitive preamplifiers

    International Nuclear Information System (INIS)

    Baturitsky, M.A.; Reutovich, S.I.; Solomashenko, N.F.

    1996-01-01

    For pt. I see ibid., vol.378, p.564-569, 1996. New monolithic low-noise process has been developed for simultaneous fabrication of high-speed low-noise 4-terminal and 3-terminal pJFETs and microwave low-noise npn BJTs. A new ion-implanted 4-terminal structure of JFET having 300 MHz cut-off frequency is designed. The process provides direct contact to a top gate and independent access to the top and bottom gates. Application of p-channel implant makes it possible to optimize the JFET pinch-off voltage without deterioration of bipolar transistor characteristics: f T ≥3 GHz, current gain β≥150, R bb' ≤15-40 Ω. (orig.)

  16. Contribution to the study of the behaviour of silicon planar transistors exposed to the 60Co γ rays

    International Nuclear Information System (INIS)

    Le Ber, J.

    1967-05-01

    This report gives an account of studies carried out on bipolar silicon planar transistors irradiated by 60 Co γ rays. The author describes the interactions on the matter of the different types of particles and he gives a brief bibliographical recall of foreign studies. The technological structure of the planar transistors is then described in order to help the understanding of the phenomena, general comments are made about the choice of measured parameters and on the statistical interpretation of results. An automatic instrument for the measurement of the gain is described and the reproducibility of the results is stated The complexity of the problem and the difficulty to predict the behaviour of the semiconductors components are clearly shown. It is stated that the observed dispersions depend on: - the electrical bias during irradiation - the injection level in the emitter-base junction during the measurement - the manufacturer for a given type - the instantaneous dose rate - the geometry used The problem is then examined from the reliability point of view and methods are given to evaluate the reliability for a given dose - 'Worst case' method - moment method - Monte Carlo method. (author) [fr

  17. The International Society for Bipolar Disorders (ISBD) Task Force Report on Antidepressant Use in Bipolar Disorders

    Science.gov (United States)

    Pacchiarotti, Isabella; Bond, David J.; Baldessarini, Ross J.; Nolen, Willem A.; Grunze, Heinz; Licht, Rasmus W.; Post, Robert M.; Berk, Michael; Goodwin, Guy M.; Sachs, Gary S.; Tondo, Leonardo; Findling, Robert L.; Youngstrom, Eric A.; Tohen, Mauricio; Undurraga, Juan; González-Pinto, Ana; Goldberg, Joseph F.; Yildiz, Ayşegül; Altshuler, Lori L.; Calabrese, Joseph R.; Mitchell, Philip B.; Thase, Michael E.; Koukopoulos, Athanasios; Colom, Francesc; Frye, Mark A.; Malhi, Gin S.; Fountoulakis, Konstantinos N.; Vázquez, Gustavo; Perlis, Roy H.; Ketter, Terence A.; Cassidy, Frederick; Akiskal, Hagop; Azorin, Jean-Michel; Valentí, Marc; Mazzei, Diego Hidalgo; Lafer, Beny; Kato, Tadafumi; Mazzarini, Lorenzo; Martínez-Aran, Anabel; Parker, Gordon; Souery, Daniel; Özerdem, Ayşegül; McElroy, Susan L.; Girardi, Paolo; Bauer, Michael; Yatham, Lakshmi N.; Zarate, Carlos A.; Nierenberg, Andrew A.; Birmaher, Boris; Kanba, Shigenobu; El-Mallakh, Rif S.; Serretti, Alessandro; Rihmer, Zoltan; Young, Allan H.; Kotzalidis, Georgios D.; MacQueen, Glenda M.; Bowden, Charles L.; Ghaemi, S. Nassir; Lopez-Jaramillo, Carlos; Rybakowski, Janusz; Ha, Kyooseob; Perugi, Giulio; Kasper, Siegfried; Amsterdam, Jay D.; Hirschfeld, Robert M.; Kapczinski, Flávio; Vieta, Eduard

    2014-01-01

    Objective The risk-benefit profile of antidepressant medications in bipolar disorder is controversial. When conclusive evidence is lacking, expert consensus can guide treatment decisions. The International Society for Bipolar Disorders (ISBD) convened a task force to seek consensus recommendations on the use of antidepressants in bipolar disorders. Method An expert task force iteratively developed consensus through serial consensus-based revisions using the Delphi method. Initial survey items were based on systematic review of the literature. Subsequent surveys included new or reworded items and items that needed to be rerated. This process resulted in the final ISBD Task Force clinical recommendations on antidepressant use in bipolar disorder. Results There is striking incongruity between the wide use of and the weak evidence base for the efficacy and safety of antidepressant drugs in bipolar disorder. Few well-designed, long-term trials of prophylactic benefits have been conducted, and there is insufficient evidence for treatment benefits with antidepressants combined with mood stabilizers. A major concern is the risk for mood switch to hypomania, mania, and mixed states. Integrating the evidence and the experience of the task force members, a consensus was reached on 12 statements on the use of antidepressants in bipolar disorder. Conclusions Because of limited data, the task force could not make broad statements endorsing antidepressant use but acknowledged that individual bipolar patients may benefit from antidepressants. Regarding safety, serotonin reuptake inhibitors and bupropion may have lower rates of manic switch than tricyclic and tetracyclic antidepressants and norepinephrine-serotonin reuptake inhibitors. The frequency and severity of antidepressant-associated mood elevations appear to be greater in bipolar I than bipolar II disorder. Hence, in bipolar I patients antidepressants should be prescribed only as an adjunct to mood-stabilizing medications

  18. Bipolar disorder and age-related functional impairment Prejuízo funcional associado à idade e transtorno bipolar

    Directory of Open Access Journals (Sweden)

    Alice Aita Cacilhas

    2009-12-01

    Full Text Available OBJECTIVE: Although bipolar disorder is a major contributor to functional impairment worldwide, an independent impact of bipolar disorder and ageing on functioning has yet to be demonstrated. The objective of the present study was to evaluate the effect of bipolar disorder on age-related functional status using matched controls as a standard. METHOD: One-hundred patients with bipolar disorder and matched controls were evaluated for disability. Age-related effects controlled for confounders were cross-sectionally evaluated. RESULTS: Patients were significantly more impaired than controls. Regression showed effects for aging in both groups. The effect, size, however, was significantly stronger in patients. CONCLUSION: Bipolar disorder was an important effect modifier of the age impact on functioning. While a longitudinal design is needed to effectively demonstrate this different impact, this study further depicts bipolar disorder as a chronic and progressively impairing illness.OBJETIVO: O transtorno bipolar é responsável por importante parcela do prejuízo funcional ao redor do mundo. Um efeito independente do transtorno bipolar e da idade no funcionamento ainda não foi demonstrado. O presente estudo tem o objetivo de avaliar o efeito do transtorno bipolar no prejuízo funcional relacionado à idade, com controles pareados como padrão. MÉTODO: Cem pacientes com transtorno bipolar e controles pareados foram avaliados para incapacidade. Efeitos relacionados à idade, com controle para confundidores, foram investigados. RESULTADOS: Pacientes tiveram significativamente mais prejuízo que controles. A regressão mostrou efeito para a idade em ambos os grupos, e o efeito foi significativamente mais forte nos pacientes. CONCLUSÃO: O transtorno bipolar foi um importante modificador de efeito no impacto da idade no funcionamento. Enquanto um desenho de estudo longitudinal é necessário para efetivamente demonstrar este impacto diferencial, este

  19. Cognitive vulnerability to bipolar disorder in offspring of parents with bipolar disorder.

    Science.gov (United States)

    Pavlickova, Hana; Turnbull, Oliver; Bentall, Richard P

    2014-11-01

    Bipolar disorder is a highly heritable illness, with a positive family history robustly predictive of its onset. It follows that studying biological children of parents with bipolar disorder may provide information about developmental pathways to the disorder. Moreover, such studies may serve as a useful test of theories that attribute a causal role in the development of mood disorders to psychological processes. Psychological style (including self-esteem, coping style with depression, domain-specific risk-taking, sensation-seeking, sensitivity to reward and punishment, and hypomanic personality and cognition) was assessed in 30 offspring of bipolar parents and 30 children of well parents. Parents of both child groups completed identical assessments. Although expected differences between parents with bipolar disorder and well parents were detected (such as low self-esteem, increased rumination, high sensitivity to reward and punishment), offspring of bipolar parents were, as a group, not significantly different from well offspring, apart from a modest trend towards lower adaptive coping. When divided into affected and non-affected subgroups, both groups of index children showed lower novelty-seeking. Only affected index children showed lower self-esteem, increased rumination, sensitivity to punishment, and hypomanic cognitions. Notably, these processes were associated with symptoms of depression. Psychological abnormalities in index offspring were associated with having met diagnostic criteria for psychiatric illnesses and the presence of mood symptoms, rather than preceding them. Implications of the present findings for our understanding of the development of bipolar disorder, as well as for informing early interventions, are discussed. © 2014 The British Psychological Society.

  20. [Lithium and anticonvulsants in bipolar depression].

    Science.gov (United States)

    Samalin, L; Nourry, A; Llorca, P-M

    2011-12-01

    For decades, lithium and anticonvulsants have been widely used in the treatment of bipolar disorder. Their efficacy in the treatment of mania is recognized. These drugs have been initially evaluated in old and methodologically heterogeneous studies. Their efficacy in bipolar depression has not always been confirmed in more recent and methodologically more reliable studies. Thus, lithium's efficacy as monotherapy was challenged by the study of Young (2008) that showed a lack of efficacy compared with placebo in the treatment of bipolar depression. In two recent meta-analyses, valproate has shown a modest efficacy in the treatment of bipolar depression. As for lithium, valproate appeared to have a larger antimanic effect for acute phase and prophylaxis of bipolar disorder. In contrast, lamotrigine is more effective on the depressive pole of bipolar disorder with better evidence for the prevention of depressive recurrences. The guidelines include these recent studies and recommend lamotrigine as a first-line treatment of bipolar depression and for maintenance treatment. Because of more discordant data concerning lithium and valproate, these two drugs are placed either as first or as second line treatment of bipolar depression. The different safety/efficacy ratios of mood stabilizers underlie the complementarity and the importance of combination between them, or with some second-generation antipsychotics, in the treatment of patients with bipolar disorder. Copyright © 2011 L’Encéphale. Published by Elsevier Masson SAS.. All rights reserved.

  1. Application of Bipolar Fuzzy Sets in Graph Structures

    Directory of Open Access Journals (Sweden)

    Muhammad Akram

    2016-01-01

    Full Text Available A graph structure is a useful tool in solving the combinatorial problems in different areas of computer science and computational intelligence systems. In this paper, we apply the concept of bipolar fuzzy sets to graph structures. We introduce certain notions, including bipolar fuzzy graph structure (BFGS, strong bipolar fuzzy graph structure, bipolar fuzzy Ni-cycle, bipolar fuzzy Ni-tree, bipolar fuzzy Ni-cut vertex, and bipolar fuzzy Ni-bridge, and illustrate these notions by several examples. We study ϕ-complement, self-complement, strong self-complement, and totally strong self-complement in bipolar fuzzy graph structures, and we investigate some of their interesting properties.

  2. 2017 Bipolar Plate Workshop Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Kopasz, John P. [Argonne National Lab. (ANL), Argonne, IL (United States); Benjamin, Thomas G. [Argonne National Lab. (ANL), Argonne, IL (United States); Schenck, Deanna [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-08-17

    The Bipolar Plate (BP) Workshop was held at USCAR1 in Southfield, Michigan on February 14, 2017 and included 63 participants from industry, government agencies, universities, and national laboratories with expertise in the relevant fields. The objective of the workshop was to identify research and development (R&D) needs, in particular early-stage R&D, for bipolar plates for polymer electrolyte membrane (PEM) fuel cells for transportation applications. The focus of the workshop was on materials, manufacturing, and design aspects of bipolar plates with the goal of meeting DOE’s 2020 bipolar plate targets. Of special interest was the cost target of ≤$3/kW for the bipolar plate.

  3. Power transistor module for high current applications

    International Nuclear Information System (INIS)

    Cilyo, F.F.

    1975-01-01

    One of the parts needed for the control system of the 400-GeV accelerator at Fermilab was a power transistor with a safe operating area of 1800A at 50V, dc current gain of 100,000 and 20 kHz bandwidth. Since the commercially available discrete devices and power hybrid packages did not meet these requirements, a power transistor module was developed which performed satisfactorily. By connecting 13 power transistors in parallel, with due consideration for network and heat dissipation problems, and by driving these 13 with another power transistor, a super power transistor is made, having an equivalent current, power, and safe operating area capability of 13 transistors. For higher capabilities, additional modules can be conveniently added. (auth)

  4. Risk factors for suicide among children and youths with bipolar spectrum and early bipolar disorder.

    Science.gov (United States)

    Rajewska-Rager, Aleksandra; Sibilski, Piotr; Lepczyńska, Natalia

    2015-01-01

    In recent years much attention has been given to determine risk factors for suicide among adults with bipolar disorder. Such studies concerning children and youths, which would also take into account the specificity of the developmental age, are still too few. The ability to identify risk factors for children and youths with mood disorders, as well as the possibility to monitor them, is an essential element in preventing suicidal behaviours. Previous studies have clearly indicated that in the group of patients with an early onset of the bipolar disorder the occurrence of suicidal thoughts and intentions were significantly increased. Identifying the risk of suicide is hindered further by the complexity of the phenomenon, which is a compound interaction of various factors: biological, environmental, sociological, psychological and clinical. This is especially true with young adults suffering from mental illness and presenting a number of other psychopathological symptoms. The following paper introduces and reviews the results of current studies, which analysed the risk factors for suicide among children and youths with bipolar spectrum or already diagnosed with bipolar disorder. For this purpose we conducted the overview of recent years literature available in PubMed/MEDLINE database, including the following search criteria: early onset bipolar disorder, bipolar disorder in children and young people, the spectrum of bipolar disorder, and suicidal ideation, suicidal intent, suicide.

  5. Lower switch rate in depressed patients with bipolar II than bipolar I disorder treated adjunctively with second-generation antidepressants

    NARCIS (Netherlands)

    Altshuler, LL; Suppes, T; Nolen, WA; Leverich, G; Keck, PE; Frye, MA; Kupka, R; McElroy, SL; Grunze, H; Kitchen, CMR; Post, R; Black, D.O.

    Objectives: The authors compared the switch rate into hypomania/mania in depressed patients treated with second-generation antidepressants who had either bipolar I or bipolar II disorder. Method: In a 10-week trial, 184 outpatients with bipolar depression (134 with bipolar I disorder, 48 with

  6. Analysing organic transistors based on interface approximation

    International Nuclear Information System (INIS)

    Akiyama, Yuto; Mori, Takehiko

    2014-01-01

    Temperature-dependent characteristics of organic transistors are analysed thoroughly using interface approximation. In contrast to amorphous silicon transistors, it is characteristic of organic transistors that the accumulation layer is concentrated on the first monolayer, and it is appropriate to consider interface charge rather than band bending. On the basis of this model, observed characteristics of hexamethylenetetrathiafulvalene (HMTTF) and dibenzotetrathiafulvalene (DBTTF) transistors with various surface treatments are analysed, and the trap distribution is extracted. In turn, starting from a simple exponential distribution, we can reproduce the temperature-dependent transistor characteristics as well as the gate voltage dependence of the activation energy, so we can investigate various aspects of organic transistors self-consistently under the interface approximation. Small deviation from such an ideal transistor operation is discussed assuming the presence of an energetically discrete trap level, which leads to a hump in the transfer characteristics. The contact resistance is estimated by measuring the transfer characteristics up to the linear region

  7. Reviewing metallic PEMFC bipolar plates

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H.; Turner, J.A. [National Renewable Energy Laboratory, Golden, CO (United States)

    2010-08-15

    A bipolar plate is one of the most important components in a polymer exchange membrane fuel cell (PEMFC) stack and has multiple functions. Metallic bipolar plate candidates have advantages over composite rivals in excellent electrical and thermal conductivity, good mechanical strength, high chemical stability, very wide alloy choices, low cost and, most importantly, existing pathways for high-volume, high-speed mass production. The challenges with metallic bipolar plates are the higher contact resistance and possible corrosion products, which may contaminate the membrane electrode assembly. This review evaluates the candidate metallic and coating materials for bipolar plates and gives the perspective of the research trends. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  8. Solid-state devices and applications

    CERN Document Server

    Lewis, Rhys

    1971-01-01

    Solid-State Devices and Applications is an introduction to the solid-state theory and its devices and applications. The book also presents a summary of all major solid-state devices available, their theory, manufacture, and main applications. The text is divided into three sections. The first part deals with the semiconductor theory and discusses the fundamentals of semiconductors; the kinds of diodes and techniques in their manufacture; the types and modes of operation of bipolar transistors; and the basic principles of unipolar transistors and their difference with bipolar transistors. The s

  9. Bipolar Disorder and Early Affective Trauma.

    Science.gov (United States)

    de Codt, Aloise; Monhonval, Pauline; Bongaerts, Xavier; Belkacemi, Ikram; Tecco, Juan Martin

    2016-09-01

    Bipolar disorder is a chronic psychiatric disease with a high prevalence and is a major psychosocial and medical burden. The exact etiological pathways of bipolar disorder are not fully understood. Genetic factors are known to play an important role in the etiology of bipolar disorder. However, high rates of discordance among identical twins and a growing body of evidence that environmental factors such as early stress can influence the onset and course of psychiatric diseases underline the importance of additional etiological mechanisms of bipolar disorders. There has been little investigation about early trauma in bipolar disorder. The aim of this study was to review the literature on the association between early traumatic interactions like child neglect, mistreatment, abuse or early parental separation and the occurrence of bipolar disorder in adulthood or impact on the course of the disease. Studies investigating associations between child neglect, mistreatment, abuse or early parental separation and occurrence of bipolar disorder in adulthood or impact on the course of the disease were searched in the Pubmed database. More than 700 articles were sorted independently by two of the authors using predefined criteria. Only research articles, reviews and meta-analyses were selected for this review. 53 articles met the inclusion criteria. To date, four systematic reviews partially addressed our research question. Early trauma is more frequently found in the past of bipolar patients than in the general population. Studies support a harmful effect of childhood trauma on the course of bipolar disease, with more anxious, depressive or psychotic symptoms, an early age of onset and a worse prognosis. Early trauma is more often found in the past of bipolar adult patients than the general population and studies support a harmful effect of childhood trauma on the course of bipolar disease, with more anxious, depressive or psychotic symptoms, an early age of onset and a

  10. Late Onset Bipolar Disorder: Case Report

    OpenAIRE

    Filipa Araújo; Adriana Horta

    2016-01-01

    Background: Bipolar disorder affects approximately 1% of the population, with diagnosis often being made during late adolescence and early adulthood, and only rarely (0.1%) in the elderly. Late onset bipolar disorder in the elderly has a impact on the nature and course of bipolar disorder. Aims: The authors report a case of bipolar disorder emerging in late life  (76years old) with no cleary identified organic cause. Conclusion: This case highlights the importance of a broad different...

  11. Distributed amplifier using Josephson vortex flow transistors

    International Nuclear Information System (INIS)

    McGinnis, D.P.; Beyer, J.B.; Nordman, J.E.

    1986-01-01

    A wide-band traveling wave amplifier using vortex flow transistors is proposed. A vortex flow transistor is a long Josephson junction used as a current controlled voltage source. The dual nature of this device to the field effect transistor is exploited. A circuit model of this device is proposed and a distributed amplifier utilizing 50 vortex flow transistors is predicted to have useful gain to 100 GHz

  12. Photosensitive graphene transistors.

    Science.gov (United States)

    Li, Jinhua; Niu, Liyong; Zheng, Zijian; Yan, Feng

    2014-08-20

    High performance photodetectors play important roles in the development of innovative technologies in many fields, including medicine, display and imaging, military, optical communication, environment monitoring, security check, scientific research and industrial processing control. Graphene, the most fascinating two-dimensional material, has demonstrated promising applications in various types of photodetectors from terahertz to ultraviolet, due to its ultrahigh carrier mobility and light absorption in broad wavelength range. Graphene field effect transistors are recognized as a type of excellent transducers for photodetection thanks to the inherent amplification function of the transistors, the feasibility of miniaturization and the unique properties of graphene. In this review, we will introduce the applications of graphene transistors as photodetectors in different wavelength ranges including terahertz, infrared, visible, and ultraviolet, focusing on the device design, physics and photosensitive performance. Since the device properties are closely related to the quality of graphene, the devices based on graphene prepared with different methods will be addressed separately with a view to demonstrating more clearly their advantages and shortcomings in practical applications. It is expected that highly sensitive photodetectors based on graphene transistors will find important applications in many emerging areas especially flexible, wearable, printable or transparent electronics and high frequency communications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Effects of carbon on phosphorus diffusion in SiGe:C and the implications on phosphorus diffusion mechanisms

    International Nuclear Information System (INIS)

    Lin, Yiheng; Xia, Guangrui; Yasuda, Hiroshi; Wise, Rick; Schiekofer, Manfred; Benna, Bernhard

    2014-01-01

    The use of carbon (C) in SiGe base layers is an important approach to control the base layer dopant phosphorus (P) diffusion and thus enhance PNP heterojunction bipolar transistor (HBT) performance. This work quantitatively investigated the carbon impacts on P diffusion in Si 0.82 Ge 0.18 :C and Si:C under rapid thermal anneal conditions. The carbon molar fraction is up to 0.32%. The results showed that the carbon retardation effect on P diffusion is less effective for Si 0.82 Ge 0.18 :C than for Si:C. In Si 0.82 Ge 0.18 :C, there is an optimum carbon content at around 0.05% to 0.1%, beyond which more carbon incorporation does not retard P diffusion any more. This behavior is different from the P diffusion behavior in Si:C and the B in Si:C and low Ge SiGe:C, which can be explained by the decreased interstitial-mediated diffusion fraction f I P, SiGe to 95% as Ge content increases to 18%. Empirical models were established to calculate the time-averaged point defect concentrations and effective diffusivities as a function of carbon and was shown to agree with previous studies on boron, phosphorus, arsenic and antimony diffusion with carbon.

  14. Bipolar outflow in B335

    International Nuclear Information System (INIS)

    Hirano, N.; Kameya, O.; Nakayama, M.; Takakubo, K.

    1988-01-01

    The high-velocity (C-12)O (J = 1-0) emission in B335 with a high angular resolution of 16 arcsec has been mapped. The high-velocity emission shows distinct bipolar pattern centered at IRAS 19345+0727, toward which a strong high-velocity (C-12)O emission has been detected. The bipolar lobes delineate remarkable collimation toward the IRAS source, indicating that the flow is focused within 0.02 pc of the driving source. Each lobe is accompanied by significant wing emission with the opposite velocity shift, which clearly shows the association with IRAS 19345+0727. This feature is well explained as a bipolar flow the axis of which is nearly perpendicular to the line of sight. There is no evidence of another evolved bipolar flow which does not associate with any dense core as previously suggested. This suggests that B335 is a site of very recent star formation, containing a single bipolar flow with an age of about 30,000 yr. 15 references

  15. Gold nanoparticle-pentacene memory-transistors

    OpenAIRE

    Novembre , Christophe; Guerin , David; Lmimouni , Kamal; Gamrat , Christian; Vuillaume , Dominique

    2008-01-01

    We demonstrate an organic memory-transistor device based on a pentacene-gold nanoparticles active layer. Gold (Au) nanoparticles are immobilized on the gate dielectric (silicon dioxide) of a pentacene transistor by an amino-terminated self-assembled monolayer. Under the application of writing and erasing pulses on the gate, large threshold voltage shift (22 V) and on/off drain current ratio of ~3E4 are obtained. The hole field-effect mobility of the transistor is similar in the on and off sta...

  16. A neuron-astrocyte transistor-like model for neuromorphic dressed neurons.

    Science.gov (United States)

    Valenza, G; Pioggia, G; Armato, A; Ferro, M; Scilingo, E P; De Rossi, D

    2011-09-01

    Experimental evidences on the role of the synaptic glia as an active partner together with the bold synapse in neuronal signaling and dynamics of neural tissue strongly suggest to investigate on a more realistic neuron-glia model for better understanding human brain processing. Among the glial cells, the astrocytes play a crucial role in the tripartite synapsis, i.e. the dressed neuron. A well-known two-way astrocyte-neuron interaction can be found in the literature, completely revising the purely supportive role for the glia. The aim of this study is to provide a computationally efficient model for neuron-glia interaction. The neuron-glia interactions were simulated by implementing the Li-Rinzel model for an astrocyte and the Izhikevich model for a neuron. Assuming the dressed neuron dynamics similar to the nonlinear input-output characteristics of a bipolar junction transistor, we derived our computationally efficient model. This model may represent the fundamental computational unit for the development of real-time artificial neuron-glia networks opening new perspectives in pattern recognition systems and in brain neurophysiology. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Bipolar mixed features - Results from the comparative effectiveness for bipolar disorder (Bipolar CHOICE) study.

    Science.gov (United States)

    Tohen, Mauricio; Gold, Alexandra K; Sylvia, Louisa G; Montana, Rebecca E; McElroy, Susan L; Thase, Michael E; Rabideau, Dustin J; Nierenberg, Andrew A; Reilly-Harrington, Noreen A; Friedman, Edward S; Shelton, Richard C; Bowden, Charles L; Singh, Vivek; Deckersbach, Thilo; Ketter, Terence A; Calabrese, Joseph R; Bobo, William V; McInnis, Melvin G

    2017-08-01

    DSM-5 changed the criteria from DSM-IV for mixed features in mood disorder episodes to include non-overlapping symptoms of depression and hypomania/mania. It is unknown if, by changing these criteria, the same group would qualify for mixed features. We assessed how those meeting DSM-5 criteria for mixed features compare to those meeting DSM-IV criteria. We analyzed data from 482 adult bipolar patients in Bipolar CHOICE, a randomized comparative effectiveness trial. Bipolar diagnoses were confirmed through the MINI International Neuropsychiatric Interview (MINI). Presence and severity of mood symptoms were collected with the Bipolar Inventory of Symptoms Scale (BISS) and linked to DSM-5 and DSM-IV mixed features criteria. Baseline demographics and clinical variables were compared between mood episode groups using ANOVA for continuous variables and chi-square tests for categorical variables. At baseline, the frequency of DSM-IV mixed episodes diagnoses obtained with the MINI was 17% and with the BISS was 20%. Using DSM-5 criteria, 9% of participants met criteria for hypomania/mania with mixed features and 12% met criteria for a depressive episode with mixed features. Symptom severity was also associated with increased mixed features with a high rate of mixed features in patients with mania/hypomania (63.8%) relative to those with depression (8.0%). Data on mixed features were collected at baseline only and thus do not reflect potential patterns in mixed features within this sample across the study duration. The DSM-5 narrower, non-overlapping definition of mixed episodes resulted in fewer patients who met mixed criteria compared to DSM-IV. Copyright © 2017. Published by Elsevier B.V.

  18. Brief Report: A Family Risk Study Exploring Bipolar Spectrum Problems and Cognitive Biases in Adolescent Children of Bipolar Parents

    Science.gov (United States)

    Espie, Jonathan; Jones, Steven H.; Vance, Yvonne H.; Tai, Sara J.

    2012-01-01

    Children of parents with bipolar disorder are at increased risk of bipolar spectrum diagnoses. This cross-sectional study explores cognitive factors in the prediction of vulnerability to bipolar disorder. Adolescents at high-risk (with a parent with bipolar disorder; n = 23) and age and gender matched adolescents (n = 24) were recruited. Parent…

  19. Transport of carbon ion test particles and hydrogen recycling in the plasma of the Columbia tokamak ''HBT'' [High Beta Tokamak

    International Nuclear Information System (INIS)

    Wang, Jian-Hua.

    1990-01-01

    Carbon impurity ion transport is studied in the Columbia High Beta Tokamak (HBT), using a carbon tipped probe which is inserted into the plasma (n e ∼ 1 - 5 x 10 14 (cm -3 ), T e ∼ 4 - 10 (eV), B t ∼ 0.2 - 0.4(T)). Carbon impurity light, mainly the strong lines of C II (4267A, emitted by the C + ions) and C III (4647A, emitted by the C ++ ions), is formed by the ablation or sputtering of plasma ions and by the discharge of the carbon probe itself. The diffusion transport of the carbon ions is modeled by measuring the space-and-time dependent spectral light emission of the carbon ions with a collimated optical beam and photomultiplier. The point of emission can be observed in such a way as to sample regions along and transverse to the toroidal magnetic field. The carbon ion diffusion coefficients are obtained by fitting the data to a diffusion transport model. It is found that the diffusion of the carbon ions is ''classical'' and is controlled by the high collisionality of the HBT plasma; the diffusion is a two-dimensional problem and the expected dependence on the charge of the impurity ion is observed. The measurement of the spatial distribution of the H α emissivity was obtained by inverting the light signals from a 4-channel polychromator, the data were used to calculate the minor-radial influx, the density, and the recycling time of neutral hydrogen atoms or molecules. The calculation shows that the particle recycling time τ p is comparable with the plasma energy confinement time τ E ; therefore, the recycling of the hot plasma ions with the cold neutrals from the walls is one of the main mechanisms for loss of plasma energy

  20. Three times more days depressed than manic or hypomanic in both bipolar I and bipolar II disorder

    NARCIS (Netherlands)

    Kupka, Ralph W.; Altshuler, Lori L.; Nolen, Willem A.; Suppes, Trisha; Luckenbaugh, David A.; Leverich, Gabriele S.; Frye, Mark A.; Keck, Paul E.; McElroy, Susan L.; Grunze, Heinz; Post, Robert M.

    Objectives: To assess the proportion of time spent in mania, depression and euthymia in a large cohort of bipolar subjects studied longitudinally, and to investigate depression/mania ratios in patients with bipolar I versus bipolar II disorder. Methods: Clinician-adjusted self-ratings of mood were

  1. Quetiapine monotherapy for bipolar depression

    Directory of Open Access Journals (Sweden)

    Michael E Thase

    2008-03-01

    Full Text Available Michael E ThaseDepartments of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA, USA; the Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA; and the University of Pittsburgh Medical Center, Pittsburgh, PA, USAAbstract: Bipolar depression is more common, disabling, and difficult-to-treat than the manic and hypomanic phases that define bipolar disorder. Unlike the treatment of so-called “unipolar” depressions, antidepressants generally are not indicated as monotherapies for bipolar depressions and recent studies suggest that - even when used in combination with traditional mood stabilizers – antidepressants may have questionable value for bipolar depression. The current practice is that mood stabilizers are initiated first as monotherapies; however, the antidepressant efficacy of lithium and valproate is modest at best. Within this context the role of atypical antipsychotics is being evaluated. The combination of olanzapine and the antidepressant fluoxetine was the first treatment to receive regulatory approval in the US specifically for bipolar I depression. Quetiapine was the second medication to be approved for this indication, largely as the result of two pivotal trials known by the acronyms of BOLDER (BipOLar DEpRession I and II. Both studies demonstrated that two doses of quetiapine (300 mg and 600 mg given once daily at bedtime were significantly more effective than placebo, with no increased risk of patients switching into mania. Pooling the two studies, quetiapine was effective for both bipolar I and bipolar II depressions and for patients with (and without a history of rapid cycling. The two doses were comparably effective in both studies. Although the efficacy of quetiapine monotherapy has been established, much additional research is necessary. Further studies are needed to more fully investigate dose-response relationships and comparing quetiapine monotherapy to other mood stabilizers

  2. InAlGaAs/InP light-emitting transistors operating near 1.55 μm

    International Nuclear Information System (INIS)

    Huang Yong; Zhang Xuebing; Ryou, Jae-Hyun; Dupuis, Russell D.; Dixon, Forest; Holonyak, Nick Jr.; Feng, Milton

    2008-01-01

    Light-emitting transistors (LETs) operating at around 1.55 μm were investigated using InP/InAlGaAs heterostructures grown by metal organic chemical vapor deposition. By incorporating InGaAs quantum wells (QWs) in the base region of the N-InP/p-InAlGaAs/N-InAlAs heterojunction bipolar transistors, LET structures were achieved with a current gain of 45 and light emission at a wavelength of 1.65 μm. The light output was found to be dependent on the base current. The larger the number of QWs incorporated in the base of the LETs, the larger the light output, with correspondingly reduced current gain. Secondary ion mass spectroscopy shows that the p-type dopant, zinc (Zn), which is commonly used in the growth of InAlGaAs, diffuses into the emitter and the base active QW region, leading to compromised electrical performance and light output intensity. Increasing the Zn doping level in the barrier layers of the QW structure causes the photoluminescence efficiency to decrease rapidly. Consequently, an alternative low-diffusivity dopant, carbon (C), was studied and a LET with a C-doped base was grown and fabricated. The highest light output was demonstrated for the C-doped LETs owing to the improved quality of the active layer

  3. Cross Entropy Measures of Bipolar and Interval Bipolar Neutrosophic Sets and Their Application for Multi-Attribute Decision-Making

    Directory of Open Access Journals (Sweden)

    Surapati Pramanik

    2018-03-01

    Full Text Available The bipolar neutrosophic set is an important extension of the bipolar fuzzy set. The bipolar neutrosophic set is a hybridization of the bipolar fuzzy set and neutrosophic set. Every element of a bipolar neutrosophic set consists of three independent positive membership functions and three independent negative membership functions. In this paper, we develop cross entropy measures of bipolar neutrosophic sets and prove their basic properties. We also define cross entropy measures of interval bipolar neutrosophic sets and prove their basic properties. Thereafter, we develop two novel multi-attribute decision-making strategies based on the proposed cross entropy measures. In the decision-making framework, we calculate the weighted cross entropy measures between each alternative and the ideal alternative to rank the alternatives and choose the best one. We solve two illustrative examples of multi-attribute decision-making problems and compare the obtained result with the results of other existing strategies to show the applicability and effectiveness of the developed strategies. At the end, the main conclusion and future scope of research are summarized.

  4. Bipolar plates for PEM fuel cells

    Science.gov (United States)

    Middelman, E.; Kout, W.; Vogelaar, B.; Lenssen, J.; de Waal, E.

    The bipolar plates are in weight and volume the major part of the PEM fuel cell stack, and are also a significant contributor to the stack costs. The bipolar plate is therefore a key component if power density has to increase and costs must come down. Three cell plate technologies are expected to reach targeted cost price levels, all having specific advantages and drawbacks. NedStack has developed a conductive composite materials and a production process for fuel cell plates (bipolar and mono-polar). The material has a high electric and thermal conductivity, and can be processed into bipolar plates by a proprietary molding process. Process cycle time has been reduced to less than 10 s, making the material and process suitable for economical mass production. Other development work to increase material efficiency resulted in thin bipolar plates with integrated cooling channels, and integrated seals, and in two-component bipolar plates. Total thickness of the bipolar plates is now less than 3 mm, and will be reduced to 2 mm in the near future. With these thin integrated plates it is possible to increase power density up to 2 kW/l and 2 kW/kg, while at the same time reducing cost by integrating other functions and less material use.

  5. Direct coupled amplifiers using field effect transistors

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, E P [Control and Instrumentation Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

    1964-03-15

    The concept of the uni-polar field effect transistor (P.E.T.) was known before the invention of the bi-polar transistor but it is only recently that they have been made commercially. Being produced as yet only in small quantities, their price imposes a restriction on use to circuits where their peculiar properties can be exploited to the full. One such application is described here where the combination of low voltage drift and relatively low input leakage current are necessarily used together. One of the instruments used to control nuclear reactors has a logarithmic response to the mean output current from a polarised ionisation chamber. The logarithmic signal is then differentiated electrically, the result being displayed on a meter calibrated to show the reactor divergence or doubling time. If displayed in doubling time the scale is calibrated reciprocally. Because of the wide range obtained in the logarithmic section and the limited supply voltage, an output of 1 volt per decade change in ionisation current is used. Differentiating this gives a current of 1.5 x 10{sup -8} A for p.s.D. (20 sec. doubling time) in the differentiating amplifier. To overcome some of the problems of noise due to statistical variations in input current, the circuit design necessitates a resistive path to ground at the amplifier input of 20 M.ohms. A schematic diagram is shown. 1. It is evident that a zero drift of 1% can be caused by a leakage current of 1.5 x 10{sup -10} A or an offset voltage of 3 mV at the amplifier input. Although the presently used electrometer valve is satisfactory from the point of view of grid current, there have been sudden changes in grid to grid voltage (the valve is a double triode) of up to 10 m.V. It has been found that a pair of F.E.T's. can be used to replace the electrometer valve so long as care is taken in correct balance of the two devices. An investigation has been made into the characteristics of some fourteen devices to see whether those with

  6. Electronic monitoring in bipolar disorder.

    Science.gov (United States)

    Faurholt-Jepsen, Maria

    2018-03-01

    Major reasons for the insufficient effects of current treatment options in bipolar disorder include delayed intervention for prodromal depressive and manic symptoms and decreased adherence to psychopharmacological treatment. The reliance on subjective information and clinical evaluations when diagnosing and assessing the severity of depressive and manic symptoms calls for less biased and more objective markers. By using electronic devices, fine-grained data on complex psychopathological aspects of bipolar disorder can be evaluated unobtrusively over the long term. Moreover, electronic data could possibly represent candidate markers of diagnosis and illness activity in bipolar disorder and allow for early and individualized intervention for prodromal symptoms outside clinical settings. 
The present dissertation concerns the use of electronic monitoring as a marker and treatment intervention in bipolar disorder and investigated the scientific literature and body of evidence within the area, which includes ten original study reports and two systematic reviews, one of which included a meta-analysis, conducted by the author of the dissertation. 
Taken together, the literature presented in this dissertation illustrates that 1) smartphone-based electronic self-monitoring of mood seems to reflect clinically assessed depressive and manic symptoms and enables the long-term characterization of mood

instability in bipolar disorder; 2) preliminary results suggest that smartphone-based automatically generated data (e.g. the number of text messages sent/day; the number of incoming and outgoing calls/day; the number of changes in cell tower IDs/day; and voice features) seem to reflect clinically assessed depressive and manic symptoms in bipolar disorder; 3) smartphone-based electronic self-monitoring had no effects on the severity of depressive and manic symptoms in bipolar disorder, according to a randomized controlled trial; and 4) electronic monitoring of psychomotor

  7. Prediction of transition from common adolescent bipolar experiences to bipolar disorder: 10-year study.

    Science.gov (United States)

    Tijssen, Marijn J A; van Os, Jim; Wittchen, Hans-Ulrich; Lieb, Roselind; Beesdo, Katja; Mengelers, Ron; Wichers, Marieke

    2010-02-01

    Although (hypo)manic symptoms are common in adolescence, transition to adult bipolar disorder is infrequent. To examine whether the risk of transition to bipolar disorder is conditional on the extent of persistence of subthreshold affective phenotypes. In a 10-year prospective community cohort study of 3021 adolescents and young adults, the association between persistence of affective symptoms over 3 years and the 10-year clinical outcomes of incident DSM-IV (hypo)manic episodes and incident use of mental healthcare was assessed. Transition to clinical outcome was associated with persistence of symptoms in a dose-dependent manner. Around 30-40% of clinical outcomes could be traced to prior persistence of affective symptoms. In a substantial proportion of individuals, onset of clinical bipolar disorder may be seen as the poor outcome of a developmentally common and usually transitory non-clinical bipolar phenotype.

  8. Alcoholism and anxiety in bipolar illness : Differential lifetime anxiety comorbidity in bipolar I women with and without alcoholism

    NARCIS (Netherlands)

    Levander, Eric; Frye, Mark A.; McElroy, Susan; Suppes, Trisha; Grunze, Heinz; Nolen, Willem A.; Kupka, Ralph; Keck, Paul E.; Leverich, Gabriele S.; Altshuler, Lori L.; Hwang, Sun; Mintz, Jim; Post, Robert M.

    Introduction: This study was undertaken to evaluate the prevalence rate of anxiety comorbidity in bipolar subjects with and without alcohol use disorders (AUD). Methods: Bipolar men and women who entered the Stanley Foundation Bipolar Network (SFBN) underwent a Structured Clinical Interview for

  9. "Is it menopause or bipolar?": a qualitative study of the experience of menopause for women with bipolar disorder.

    Science.gov (United States)

    Perich, Tania; Ussher, Jane; Parton, Chloe

    2017-11-16

    Menopause can be a time of change for women and may be marked by disturbances in mood. For women living with a mental illness, such as bipolar disorder, little is known about how they experience mood changes during menopause. This study aimed to explore how women with bipolar disorder constructed mood changes during menopause and how this impacted on treatment decisions. Semi-structured interviews were undertaken with fifteen women who reported they had been diagnosed with bipolar disorder. Data was analysed using thematic analysis guided by a social constructionist framework. Themes identified included 'Constructions of mood change: menopause or bipolar disorder?',' Life events, bipolar disorder and menopause coming together'; 'Treatment choices for mood change during menopause'. The accounts suggested that women related to the experience of mood changes during menopause through the lens of their existing framework of bipolar disorder, with implications for understanding of self and treatment choices.

  10. Reconfigurable Complementary Logic Circuits with Ambipolar Organic Transistors.

    Science.gov (United States)

    Yoo, Hocheon; Ghittorelli, Matteo; Smits, Edsger C P; Gelinck, Gerwin H; Lee, Han-Koo; Torricelli, Fabrizio; Kim, Jae-Joon

    2016-10-20

    Ambipolar organic electronics offer great potential for simple and low-cost fabrication of complementary logic circuits on large-area and mechanically flexible substrates. Ambipolar transistors are ideal candidates for the simple and low-cost development of complementary logic circuits since they can operate as n-type and p-type transistors. Nevertheless, the experimental demonstration of ambipolar organic complementary circuits is limited to inverters. The control of the transistor polarity is crucial for proper circuit operation. Novel gating techniques enable to control the transistor polarity but result in dramatically reduced performances. Here we show high-performance non-planar ambipolar organic transistors with electrical control of the polarity and orders of magnitude higher performances with respect to state-of-art split-gate ambipolar transistors. Electrically reconfigurable complementary logic gates based on ambipolar organic transistors are experimentally demonstrated, thus opening up new opportunities for ambipolar organic complementary electronics.

  11. Ultra-high gain diffusion-driven organic transistor

    Science.gov (United States)

    Torricelli, Fabrizio; Colalongo, Luigi; Raiteri, Daniele; Kovács-Vajna, Zsolt Miklós; Cantatore, Eugenio

    2016-01-01

    Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field-effect transistors show limited gain, usually of the order of tens, because of the large contact resistance and channel-length modulation. Here we show a new organic field-effect transistor architecture with a gain larger than 700. This is the highest gain ever reported for organic field-effect transistors. In the proposed organic field-effect transistor, the charge injection and extraction at the metal–semiconductor contacts are driven by the charge diffusion. The ideal conditions of ohmic contacts with negligible contact resistance and flat current saturation are demonstrated. The approach is general and can be extended to any thin-film technology opening unprecedented opportunities for the development of high-performance flexible electronics. PMID:26829567

  12. High-Performance Vertical Organic Electrochemical Transistors.

    Science.gov (United States)

    Donahue, Mary J; Williamson, Adam; Strakosas, Xenofon; Friedlein, Jacob T; McLeod, Robert R; Gleskova, Helena; Malliaras, George G

    2018-02-01

    Organic electrochemical transistors (OECTs) are promising transducers for biointerfacing due to their high transconductance, biocompatibility, and availability in a variety of form factors. Most OECTs reported to date, however, utilize rather large channels, limiting the transistor performance and resulting in a low transistor density. This is typically a consequence of limitations associated with traditional fabrication methods and with 2D substrates. Here, the fabrication and characterization of OECTs with vertically stacked contacts, which overcome these limitations, is reported. The resulting vertical transistors exhibit a reduced footprint, increased intrinsic transconductance of up to 57 mS, and a geometry-normalized transconductance of 814 S m -1 . The fabrication process is straightforward and compatible with sensitive organic materials, and allows exceptional control over the transistor channel length. This novel 3D fabrication method is particularly suited for applications where high density is needed, such as in implantable devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Bipolar Plates for PEM Systems

    OpenAIRE

    Lædre, Sigrid

    2016-01-01

    Summary of thesis: The Bipolar Plate (BPP) is an important component in both Proton Exchange Membrane Fuel Cells (PEMFCs) and Proton Exchange Membrane Water Electrolyzers (PEMWEs). Bipolar plate material and processing constitutes for a large fraction of the cost and weight of a PEM cell stack. The main tasks for the bipolar plates in both systems are to separate single cell in a stack, conduct current between single cells and remove heat from active areas. In addition, the BPPs distribu...

  14. Modeling suicide in bipolar disorders.

    Science.gov (United States)

    Malhi, Gin S; Outhred, Tim; Das, Pritha; Morris, Grace; Hamilton, Amber; Mannie, Zola

    2018-02-19

    Suicide is a multicausal human behavior, with devastating and immensely distressing consequences. Its prevalence is estimated to be 20-30 times greater in patients with bipolar disorders than in the general population. The burden of suicide and its high prevalence in bipolar disorders make it imperative that our current understanding be improved to facilitate prediction of suicide and its prevention. In this review, we provide a new perspective on the process of suicide in bipolar disorder, in the form of a novel integrated model that is derived from extant knowledge and recent evidence. A literature search of articles on suicide in bipolar disorder was conducted in recognized databases such as Scopus, PubMed, and PsycINFO using the keywords "suicide", "suicide in bipolar disorders", "suicide process", "suicide risk", "neurobiology of suicide" and "suicide models". Bibliographies of identified articles were further scrutinized for papers and book chapters of relevance. Risk factors for suicide in bipolar disorders are well described, and provide a basis for a framework of epigenetic mechanisms, moderated by neurobiological substrates, neurocognitive functioning, and social inferences within the environment. Relevant models and theories include the diathesis-stress model, the bipolar model of suicide and the ideation-to-action models, the interpersonal theory of suicide, the integrated motivational-volitional model, and the three-step theory. Together, these models provide a basis for the generation of an integrated model that illuminates the suicidal process, from ideation to action. Suicide is complex, and it is evident that a multidimensional and integrated approach is required to reduce its prevalence. The proposed model exposes and provides access to components of the suicide process that are potentially measurable and may serve as novel and specific therapeutic targets for interventions in the context of bipolar disorder. Thus, this model is useful not only

  15. Depression and Bipolar Support Alliance

    Science.gov (United States)

    Depression and Bipolar Support Alliance Crisis Hotline Information Coping with a Crisis Suicide Prevention Information Psychiatric Hospitalization ... sign-up Education info, training, events Mood Disorders Depression Bipolar Disorder Anxiety Screening Center Co-occurring Illnesses/ ...

  16. Late Onset Bipolar Disorder: Case Report

    Directory of Open Access Journals (Sweden)

    Filipa Araújo

    2016-07-01

    Full Text Available Background: Bipolar disorder affects approximately 1% of the population, with diagnosis often being made during late adolescence and early adulthood, and only rarely (0.1% in the elderly. Late onset bipolar disorder in the elderly has a impact on the nature and course of bipolar disorder. Aims: The authors report a case of bipolar disorder emerging in late life  (76years old with no cleary identified organic cause. Conclusion: This case highlights the importance of a broad differential diagnosis and pharmacologic management when approaching new-onset manic/depressive symptoms among geriatric patients.

  17. Preamplifier design with wide bandwidth using InGaP/GaAs HBT for 10-Gbps photoreceiver module

    International Nuclear Information System (INIS)

    Hong, S. E.; Lim, J. M.; Kim, S. I.; Nam, E. S.

    2004-01-01

    We report a preamplifier with wide bandwidth using high-speed and reliable InGaP/GaAs HBT applicable for 10-Gbps photoreceiver modules. The three-stage preamplifier with a negative feedback resistor demonstrates an effective transimpedance gain of 43 dBΩ, a -3-dB bandwidth of 14 GHz corresponding to a very high transimpedance-bandwidth product of 2.52 THzΩ, and an output return loss of -18 dB up to -3-dB bandwidth. This compact circuit is fabricated with an area of 800 X 700 μm 2 . A photoreceiver module of surface-mountable package type, that is composed of preamplifier and photodiode of surface-illumination type, demonstrates an optical bandwidth of 7.5 GHz at λ = 1.55 μ m and a 45-psec rise/fall time for 10-Gbps. The module shows higher sensitivity for a 10-Gbps optical transmission system.

  18. High transconductance organic electrochemical transistors

    Science.gov (United States)

    Khodagholy, Dion; Rivnay, Jonathan; Sessolo, Michele; Gurfinkel, Moshe; Leleux, Pierre; Jimison, Leslie H.; Stavrinidou, Eleni; Herve, Thierry; Sanaur, Sébastien; Owens, Róisín M.; Malliaras, George G.

    2013-07-01

    The development of transistors with high gain is essential for applications ranging from switching elements and drivers to transducers for chemical and biological sensing. Organic transistors have become well-established based on their distinct advantages, including ease of fabrication, synthetic freedom for chemical functionalization, and the ability to take on unique form factors. These devices, however, are largely viewed as belonging to the low-end of the performance spectrum. Here we present organic electrochemical transistors with a transconductance in the mS range, outperforming transistors from both traditional and emerging semiconductors. The transconductance of these devices remains fairly constant from DC up to a frequency of the order of 1 kHz, a value determined by the process of ion transport between the electrolyte and the channel. These devices, which continue to work even after being crumpled, are predicted to be highly relevant as transducers in biosensing applications.

  19. High transconductance organic electrochemical transistors

    Science.gov (United States)

    Khodagholy, Dion; Rivnay, Jonathan; Sessolo, Michele; Gurfinkel, Moshe; Leleux, Pierre; Jimison, Leslie H.; Stavrinidou, Eleni; Herve, Thierry; Sanaur, Sébastien; Owens, Róisín M.; Malliaras, George G.

    2013-01-01

    The development of transistors with high gain is essential for applications ranging from switching elements and drivers to transducers for chemical and biological sensing. Organic transistors have become well-established based on their distinct advantages, including ease of fabrication, synthetic freedom for chemical functionalization, and the ability to take on unique form factors. These devices, however, are largely viewed as belonging to the low-end of the performance spectrum. Here we present organic electrochemical transistors with a transconductance in the mS range, outperforming transistors from both traditional and emerging semiconductors. The transconductance of these devices remains fairly constant from DC up to a frequency of the order of 1 kHz, a value determined by the process of ion transport between the electrolyte and the channel. These devices, which continue to work even after being crumpled, are predicted to be highly relevant as transducers in biosensing applications. PMID:23851620

  20. Recent progress in photoactive organic field-effect transistors.

    Science.gov (United States)

    Wakayama, Yutaka; Hayakawa, Ryoma; Seo, Hoon-Seok

    2014-04-01

    Recent progress in photoactive organic field-effect transistors (OFETs) is reviewed. Photoactive OFETs are divided into light-emitting (LE) and light-receiving (LR) OFETs. In the first part, LE-OFETs are reviewed from the viewpoint of the evolution of device structures. Device performances have improved in the last decade with the evolution of device structures from single-layer unipolar to multi-layer ambipolar transistors. In the second part, various kinds of LR-OFETs are featured. These are categorized according to their functionalities: phototransistors, non-volatile optical memories, and photochromism-based transistors. For both, various device configurations are introduced: thin-film based transistors for practical applications, single-crystalline transistors to investigate fundamental physics, nanowires, multi-layers, and vertical transistors based on new concepts.

  1. Recent progress in photoactive organic field-effect transistors

    International Nuclear Information System (INIS)

    Wakayama, Yutaka; Hayakawa, Ryoma; Seo, Hoon-Seok

    2014-01-01

    Recent progress in photoactive organic field-effect transistors (OFETs) is reviewed. Photoactive OFETs are divided into light-emitting (LE) and light-receiving (LR) OFETs. In the first part, LE-OFETs are reviewed from the viewpoint of the evolution of device structures. Device performances have improved in the last decade with the evolution of device structures from single-layer unipolar to multi-layer ambipolar transistors. In the second part, various kinds of LR-OFETs are featured. These are categorized according to their functionalities: phototransistors, non-volatile optical memories, and photochromism-based transistors. For both, various device configurations are introduced: thin-film based transistors for practical applications, single-crystalline transistors to investigate fundamental physics, nanowires, multi-layers, and vertical transistors based on new concepts. (review)

  2. Suprasensory phenomena in those with a bipolar disorder.

    Science.gov (United States)

    Parker, Gordon; Paterson, Amelia; Romano, Mia; Granville Smith, Isabelle

    2018-03-01

    To increase awareness of the sensory changes experienced during hypo/manic and depressive states by those with a bipolar disorder and determine if the prevalence of such features is similar across differing bipolar sub-types. We interviewed 66 patients who acknowledged sensory changes during hypo/manic states. They were allocated to bipolar I, bipolar II and soft bipolar diagnostic categories and the prevalence of 10 differing sensory changes was quantified during hypo/manic and depressive phases. Bipolar I patients were just as likely, if not more likely, to report suprasensory changes which typically involved enhancement of senses during hypo/manic phases and muting or blunting during depressive phases. The high prevalence of changes in intuition, empathy, appreciation of danger and predictive capacities suggests that these are more part of the intrinsic bipolar mood domain states and not necessarily suprasensory, while changes in primary senses of smell, taste, vision, touch and hearing appear to more commonly define the suprasensory domain. It is important for clinicians and patients with a bipolar disorder to be aware of non-psychotic, suprasensory phenomena. Identification of such features may aid diagnosis and also explain the recognised increased creativity in those with a bipolar condition.

  3. The bipolarity of light and dark: A review on Bipolar Disorder and circadian cycles.

    Science.gov (United States)

    Abreu, T; Bragança, M

    2015-10-01

    Bipolar Disorder is characterized by episodes running the full mood spectrum, from mania to depression. Between mood episodes, residual symptoms remain, as sleep alterations, circadian cycle disturbances, emotional deregulation, cognitive impairment and increased risk for comorbidities. The present review intends to reflect about the most recent and relevant information concerning the biunivocal relation between bipolar disorder and circadian cycles. It was conducted a literature search on PubMed database using the search terms "bipolar", "circadian", "melatonin", "cortisol", "body temperature", "Clock gene", "Bmal1 gene", "Per gene", "Cry gene", "GSK3β", "chronotype", "light therapy", "dark therapy", "sleep deprivation", "lithum" and "agomelatine". Search results were manually reviewed, and pertinent studies were selected for inclusion as appropriate. Several studies support the relationship between bipolar disorder and circadian cycles, discussing alterations in melatonin, body temperature and cortisol rhythms; disruption of sleep/wake cycle; variations of clock genes; and chronotype. Some therapeutics for bipolar disorder directed to the circadian cycles disturbances are also discussed, including lithium carbonate, agomelatine, light therapy, dark therapy, sleep deprivation and interpersonal and social rhythm therapy. This review provides a summary of an extensive research for the relevant literature on this theme, not a patient-wise meta-analysis. In the future, it is essential to achieve a better understanding of the relation between bipolar disorder and the circadian system. It is required to establish new treatment protocols, combining psychotherapy, therapies targeting the circadian rhythms and the latest drugs, in order to reduce the risk of relapse and improve affective behaviour. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Transtorno bipolar

    Directory of Open Access Journals (Sweden)

    Alda Martin

    1999-01-01

    Full Text Available Os resultados de estudos de famílias sugerem que o transtorno bipolar tenha uma base genética. Essa hipótese foi reforçada em estudos de adoção e de gêmeos. A herança do transtorno bipolar é complexa, envolve vários genes, além de apresentar heterogeneidade e interação entre fatores genéticos e não-genéticos. Achados, que já foram replicados, já implicaram os cromossomos 4, 12, 18 e 21, entre outros, na busca por genes de suscetibilidade. Os resultados mais promissores foram obtidos através de estudos de ligação. Por outro lado, os estudos de associação geraram dados interessantes, mas ainda vagos. Os estudos de populações de pacientes homogêneos e a melhor definição do fenótipo deverão contribuir para avanços futuros. A identificação dos genes relacionados ao transtorno bipolar irá permitir o melhor entendimento e tratamento dessa doença.

  5. Integrated neurobiology of bipolar disorder

    Directory of Open Access Journals (Sweden)

    Vladimir eMaletic

    2014-08-01

    Full Text Available From a neurobiological perspective there is no such thing as bipolar disorder. Rather, it is almost certainly the case that many somewhat similar, but subtly different, pathological conditions produce a disease state that we currently diagnose as bipolarity. This heterogeneity—reflected in the lack of synergy between our current diagnostic schema and our rapidly advancing scientific understanding of the condition—limits attempts to articulate an integrated perspective on bipolar disorder. However, despite these challenges, scientific findings in recent years are beginning to offer a provisional unified field theory of the disease. This theory sees bipolar disorder as a suite of related neurodevelopmental conditions with interconnected functional abnormalities that often appear early in life and worsen over time. In addition to accelerated loss of volume in brain areas known to be essential for mood regulation and cognitive function, consistent findings have emerged at a cellular level, providing evidence that bipolar disorder is reliably associated with dysregulation of glial-neuronal interactions. Among these glial elements are microglia—the brain’s primary immune elements, which appear to be overactive in the context of bipolarity. Multiple studies now indicate that inflammation is also increased in the periphery of the body in both the depressive and manic phases of the illness, with at least some return to normality in the euthymic state. These findings are consistent with changes in the HPA axis, which are known to drive inflammatory activation. In summary, the very fact that no single gene, pathway or brain abnormality is likely to ever account for the condition is itself an extremely important first step in better articulating an integrated perspective on both its ontological status and pathogenesis. Whether this perspective will translate into the discovery of innumerable more homogeneous forms of bipolarity is one of the great

  6. Universal power transistor base drive control unit

    Science.gov (United States)

    Gale, Allan R.; Gritter, David J.

    1988-01-01

    A saturation condition regulator system for a power transistor which achieves the regulation objectives of a Baker clamp but without dumping excess base drive current into the transistor output circuit. The base drive current of the transistor is sensed and used through an active feedback circuit to produce an error signal which modulates the base drive current through a linearly operating FET. The collector base voltage of the power transistor is independently monitored to develop a second error signal which is also used to regulate base drive current. The current-sensitive circuit operates as a limiter. In addition, a fail-safe timing circuit is disclosed which automatically resets to a turn OFF condition in the event the transistor does not turn ON within a predetermined time after the input signal transition.

  7. The Effects of Low Dose-Rate Ionizing Radiation on the Shapes of Transients in the LM124 Operational Amplifier

    Science.gov (United States)

    Buchner, Stephen; McMorrow, Dale; Roche, Nicholas; Dusseau, Laurent; Pease, Ron L.

    2008-01-01

    Shapes of single event transients (SETs) in a linear bipolar circuit (LM124) change with exposure to total ionizing dose (TID) radiation. SETs shape changes are a direct consequence of TID-induced degradation of bipolar transistor gain. A reduction in transistor gain causes a reduction in the drive current of the current sources in the circuit, and it is the lower drive current that most affects the shapes of large amplitude SETs.

  8. Nickel hydrogen bipolar battery electrode design

    Science.gov (United States)

    Puglisi, V. J.; Russell, P.; Verrier, D.; Hall, A.

    1985-01-01

    The preferred approach of the NASA development effort in nickel hydrogen battery design utilizes a bipolar plate stacking arrangement to obtain the required voltage-capacity configuration. In a bipolar stack, component designs must take into account not only the typical design considerations such as voltage, capacity and gas management, but also conductivity to the bipolar (i.e., intercell) plate. The nickel and hydrogen electrode development specifically relevant to bipolar cell operation is discussed. Nickel oxide electrodes, having variable type grids and in thicknesses up to .085 inch are being fabricated and characterized to provide a data base. A selection will be made based upon a system level tradeoff. Negative (hydrpogen) electrodes are being screened to select a high performance electrode which can function as a bipolar electrode. Present nickel hydrogen negative electrodes are not capable of conducting current through their cross-section. An electrode was tested which exhibits low charge and discharge polarization voltages and at the same time is conductive. Test data is presented.

  9. Suicide in bipolar disorder: a review.

    Science.gov (United States)

    Latalova, Klara; Kamaradova, Dana; Prasko, Jan

    2014-06-01

    Suicide is a leading cause of death in patients with bipolar disorder. Risk factors and prevention of suicide in this illness are the focus of considerable current research. MEDLINE data base was searched for the key words "bipolar disorder" with "suicide", "lithium" with "suicide", "anticonvulsants" with "bipolar disorder", and "anticonvulsants" with "bipolar disorder" and with "suicide". No language or time constraints were applied. The lists of references were searched manually to find additional articles. It is estimated that 25% to 50% of patients with bipolar disorder will attempt suicide at least once over their lifetime, and that 8% to 19% will complete suicide. Mortality rates from cardiovascular diseases are elevated in bipolar disorder. Risk factors for suicide include younger age of onset of the illness, history of past suicidal behavior, family history of suicide acts, comorbid borderline personality disorder and substance use disorders, and hopelessness. The warning signs calling for immediate action include the patients threatening to harm themselves, or looking for ways to kill themselves (seeking access to pills or weapons), or the patient talking or writing about death. Robust evidence supports the effects of lithium treatment in reducing suicidal attempts and completions in bipolar disorder. The evidence for antisuicidal effects of anticonvulsants is weaker. Nevertheless, valproate and other anticonvulsants are frequently prescribed as mood stabilizers. There have been controversial suggestions that this treatment may elevate the risk of suicide, but the data supporting this are not convincing. Psychoeducation can reduce the number of suicide attempts and completions. Suicide in bipolar disorder is a major public health problem. Recent research has expanded our knowledge of risk factors and warning signs. Nevertheless, it appears that the introduction of lithium treatment in the 1970s was the most recent important breakthrough in the prevention

  10. Charge-collection efficiency of GaAs field effect transistors fabricated with a low temperature grown buffer layer: dependence on charge deposition profile

    International Nuclear Information System (INIS)

    McMorrow, D.; Knudson, A.R.; Melinger, J.S.; Buchner, S.

    1999-01-01

    The results presented here reveal a surprising dependence of the charge-collection efficiency of LT GaAs FETs (field effect transistors) on the depth profile of the deposited charge. Investigation of the temporal dependence of the signal amplitude, carrier density contours, and potential contours reveals different mechanisms for charge collection arising from carriers deposited above and below the LT GaAs buffer layer, respectively. In particular, carriers deposited below the LT GaAs buffer layer dissipate slowly and give rise to a persistent charge collection that is associated with a bipolar-like gain process. These results may be of significance in understanding the occurrence of single-event upsets from protons, neutrons, and large-angle, glancing heavy-ion strikes. (authors)

  11. Impairment in emotion perception from body movements in individuals with bipolar I and bipolar II disorder is associated with functional capacity.

    Science.gov (United States)

    Vaskinn, Anja; Lagerberg, Trine Vik; Bjella, Thomas D; Simonsen, Carmen; Andreassen, Ole A; Ueland, Torill; Sundet, Kjetil

    2017-12-01

    Individuals with bipolar disorder present with moderate impairments in social cognition during the euthymic state. The impairment extends to theory of mind and to the perception of emotion in faces and voices, but it is unclear if emotion perception from body movements is affected. The main aim of this study was to examine if participants with bipolar disorder perform worse than healthy control participants on a task using point-light displays of human full figures moving in a manner indicative of a basic emotion (angry, happy, sad, fearful, neutral/no emotion). A secondary research question was whether diagnostic subtypes (bipolar I, bipolar II) and history of psychosis impacted on this type of emotion perception. Finally, symptomatic, neurocognitive, and functional correlates of emotion perception from body movements were investigated. Fifty-three individuals with bipolar I (n = 29) or bipolar II (n = 24) disorder, and 84 healthy control participants were assessed for emotion perception from body movements. The bipolar group also underwent clinical, cognitive, and functional assessment. Research questions were analyzed using analyses of variance and bivariate correlations. The bipolar disorder group differed significantly from healthy control participants for emotion perception from body movements (Cohen's d = 0.40). Analyses of variance yielded no effects of sex, diagnostic subtype (bipolar I, bipolar II), or history of psychosis. There was an effect of emotion, indicating that some emotions are easier to recognize. The lack of a significant group × emotion interaction effect points, however, to this being so regardless of the presence of bipolar disorder. Performance was unrelated to manic and depressive symptom load but showed significant associations with neurocognition and functional capacity. Individuals with bipolar disorder had a small but significant impairment in the ability to perceive emotions from body movement. The impairment was global, i

  12. The relationship between borderline personality disorder and bipolar disorder

    Science.gov (United States)

    Zimmerman, Mark; Morgan, Theresa A.

    2013-01-01

    It is clinically important to recognize both bipolar disorder and borderline personality disorder (BPD) in patients seeking treatment for depression, and it is important to distinguish between the two. Research considering whether BPD should be considered part of a bipolar spectrum reaches differing conclusions. We reviewed the most studied question on the relationship between BPD and bipolar disorder: their diagnostic concordance. Across studies, approximately 10% of patients with BPD had bipolar I disorder and another 10% had bipolar II disorder. Likewise, approximately 20% of bipolar II patients were diagnosed with BPD, though only 10% of bipolar I patients were diagnosed with BPD. While the comorbidity rates are substantial, each disorder is nontheless diagnosed in the absence of the other in the vast majority of cases (80% to 90%). In studies examining personality disorders broadly, other personality disorders were more commonly diagnosed in bipolar patients than was BPD. Likewise, the converse is also true: other axis I disorders such as major depression, substance abuse, and post-traumatic stress disorder are also more commonly diagnosed in patients with BPD than is bipolar disorder. These findings challenge the notion that BPD is part of the bipolar spectrum. PMID:24174890

  13. Understanding and control of bipolar self-doping in copper nitride

    Science.gov (United States)

    Fioretti, Angela N.; Schwartz, Craig P.; Vinson, John; Nordlund, Dennis; Prendergast, David; Tamboli, Adele C.; Caskey, Christopher M.; Tuomisto, Filip; Linez, Florence; Christensen, Steven T.; Toberer, Eric S.; Lany, Stephan; Zakutayev, Andriy

    2016-05-01

    Semiconductor materials that can be doped both n-type and p-type are desirable for diode-based applications and transistor technology. Copper nitride (Cu3N) is a metastable semiconductor with a solar-relevant bandgap that has been reported to exhibit bipolar doping behavior. However, deeper understanding and better control of the mechanism behind this behavior in Cu3N is currently lacking in the literature. In this work, we use combinatorial growth with a temperature gradient to demonstrate both conduction types of phase-pure, sputter-deposited Cu3N thin films. Room temperature Hall effect and Seebeck effect measurements show n-type Cu3N with 1017 electrons/cm3 for low growth temperature (≈35 °C) and p-type with 1015 holes/cm3-1016 holes/cm3 for elevated growth temperatures (50 °C-120 °C). Mobility for both types of Cu3N was ≈0.1 cm2/Vs-1 cm2/Vs. Additionally, temperature-dependent Hall effect measurements indicate that ionized defects are an important scattering mechanism in p-type films. By combining X-ray absorption spectroscopy and first-principles defect theory, we determined that VCu defects form preferentially in p-type Cu3N, while Cui defects form preferentially in n-type Cu3N, suggesting that Cu3N is a compensated semiconductor with conductivity type resulting from a balance between donor and acceptor defects. Based on these theoretical and experimental results, we propose a kinetic defect formation mechanism for bipolar doping in Cu3N that is also supported by positron annihilation experiments. Overall, the results of this work highlight the importance of kinetic processes in the defect physics of metastable materials and provide a framework that can be applied when considering the properties of such materials in general.

  14. The clinical trajectory of emerging bipolar disorder among the high-risk offspring of bipolar parents: current understanding and future considerations.

    Science.gov (United States)

    Duffy, A; Vandeleur, C; Heffer, N; Preisig, M

    2017-11-22

    Relatively little is known about the onset of bipolar disorder, yet the early illness course is already associated with significant morbidity and mortality. Therefore, characterizing the bipolar illness trajectory is key to risk prediction and early intervention advancement. In this narrative review, we discuss key findings from prospective longitudinal studies of the high-risk offspring of bipolar parents and related meta-analyses that inform us about the clinical trajectory of emerging bipolar disorder. Challenges such as phenotypic and etiologic heterogeneity and the non-specificity of early symptoms and syndromes are highlighted. Implications of the findings for both research and clinical practice are discussed. Bipolar disorder in young people at familial risk does not typically onset with a hypomanic or manic episode. Rather the first activated episode is often preceded by years of impairing psychopathological states that vary over development and across emerging bipolar subtype. Taking heterogeneity into account and adopting a more comprehensive approach to diagnosis seems necessary to advance earlier identification and our understanding of the onset of bipolar disorder.

  15. Planar-Processed Polymer Transistors.

    Science.gov (United States)

    Xu, Yong; Sun, Huabin; Shin, Eul-Yong; Lin, Yen-Fu; Li, Wenwu; Noh, Yong-Young

    2016-10-01

    Planar-processed polymer transistors are proposed where the effective charge injection and the split unipolar charge transport are all on the top surface of the polymer film, showing ideal device characteristics with unparalleled performance. This technique provides a great solution to the problem of fabrication limitations, the ambiguous operating principle, and the performance improvements in practical applications of conjugated-polymer transistors. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Methodological recommendations for cognition trials in bipolar disorder by the International Society for Bipolar Disorders Targeting Cognition Task Force

    DEFF Research Database (Denmark)

    Miskowiak, K W; Burdick, K E; Martinez-Aran, A

    2017-01-01

    OBJECTIVES: To aid the development of treatment for cognitive impairment in bipolar disorder, the International Society for Bipolar Disorders (ISBD) convened a task force to create a consensus-based guidance paper for the methodology and design of cognition trials in bipolar disorder. METHODS...... of treatments to illness stage and using a multimodal approach. CONCLUSIONS: This ISBD task force guidance paper provides the first consensus-based recommendations for cognition trials in bipolar disorder. Adherence to these recommendations will likely improve the sensitivity in detecting treatment efficacy...

  17. Basic matrix algebra and transistor circuits

    CERN Document Server

    Zelinger, G

    1963-01-01

    Basic Matrix Algebra and Transistor Circuits deals with mastering the techniques of matrix algebra for application in transistors. This book attempts to unify fundamental subjects, such as matrix algebra, four-terminal network theory, transistor equivalent circuits, and pertinent design matters. Part I of this book focuses on basic matrix algebra of four-terminal networks, with descriptions of the different systems of matrices. This part also discusses both simple and complex network configurations and their associated transmission. This discussion is followed by the alternative methods of de

  18. Graphene-based flexible and stretchable thin film transistors.

    Science.gov (United States)

    Yan, Chao; Cho, Jeong Ho; Ahn, Jong-Hyun

    2012-08-21

    Graphene has been attracting wide attention owing to its superb electronic, thermal and mechanical properties. These properties allow great applications in the next generation of optoelectronics, where flexibility and stretchability are essential. In this context, the recent development of graphene growth/transfer and its applications in field-effect transistors are involved. In particular, we provide a detailed review on the state-of-the-art of graphene-based flexible and stretchable thin film transistors. We address the principles of fabricating high-speed graphene analog transistors and the key issues of producing an array of graphene-based transistors on flexible and stretchable substrates. It provides a platform for future work to focus on understanding and realizing high-performance graphene-based transistors.

  19. VALPROATE, BIPOLAR DISORDER AND POLYCYSTIC OVARIAN SYNDROME.

    Science.gov (United States)

    Okanović, Milana; Zivanović, Olga

    2016-01-01

    Polycystic ovarian syndrome is a syndrome of ovarian dysfunction with the principal features of hyperandrogenism and polycystic ovary morphology. A large number of studies conducted on this topic have suggested a possible role of anticonvulsants, particularly valproate, in the pathogenesis or risk factors associated with polycystic ovarian syndrome. Bipolar treatment guidelines from Canada and the United States of America recommend valproate as the first line strategy in the acute treatment of bipolar disorder. Most persons with bipolar disorder require maintenance treatment. Long-term administration of valproate in women with bipolar disorder or epilepsy is believed to result in the increased risk of hyperandrogenism, menstrual abnormalities and polycystic ovaries. Valproate may also increase the risk of infertility and other associated symptoms of polycystic ovarian syndrome. Therefore, particular caution is indicated in the use of valproate in women of reproductive age. The treatment of the female patients with bipolar disorder presents various challenges for the clinician. Every woman of reproductive age needs to know the risk and benefits of her pharmacologic treatment options. Bipolar disorder should be considered chronic disorder, whose development is largely affected by hormonal changes and reproductive cycle in women. These issues should be researched more thoroughly in order to opt for the most appropriate treatment in women with bipolar disorder.

  20. Distinctions of bipolar disorder symptoms in adolescence.

    Science.gov (United States)

    Gudiene, Devika; Leskauskas, Darius; Markeviciūte, Aurelija; Klimavicius, Dalius; Adomaitiene, Virginija

    2008-01-01

    Bipolar disorder in adolescents is a serious mental illness with problematic diagnosis that adversely affects social, academic, emotional, and family functioning. The objective of this study was to analyze features of premorbid and clinical symptoms, comorbidity, and course of bipolar disorder in adolescence. Data for analysis were collected from all case histories (N=6) of 14-18-year-old patients, hospitalized with diagnosis of bipolar disorder in the Unit of Children's and Adolescents' Psychiatry, Department of Psychiatry, Hospital of Kaunas University of Medicine, during the period from 2000 to 2005. Analysis of bipolar disorder course showed that five patients previously had been diagnosed with an episode of depression. The most frequent symptoms typical to bipolar disorder were disobedience and impulsive behavior, rapid changes of mood. The most common premorbid features were frequent changes of mood, being active in communication, hyperactive behavior. Adolescence-onset bipolar disorder was frequently comorbid with emotionally instable personality disorder, borderline type. Findings of the study confirm the notion that oppositional or impulsive behavior, rapid changes of mood without any reason, dysphoric mood and euphoric mood episodes with increased energy were cardinal symptoms of bipolar disorder with mania in adolescents. Most frequent premorbid features of these patients were quite similar to attention-deficit/hyperactivity disorder making differential diagnosis problematic.

  1. Highly Crumpled All-Carbon Transistors for Brain Activity Recording.

    Science.gov (United States)

    Yang, Long; Zhao, Yan; Xu, Wenjing; Shi, Enzheng; Wei, Wenjing; Li, Xinming; Cao, Anyuan; Cao, Yanping; Fang, Ying

    2017-01-11

    Neural probes based on graphene field-effect transistors have been demonstrated. Yet, the minimum detectable signal of graphene transistor-based probes is inversely proportional to the square root of the active graphene area. This fundamentally limits the scaling of graphene transistor-based neural probes for improved spatial resolution in brain activity recording. Here, we address this challenge using highly crumpled all-carbon transistors formed by compressing down to 16% of its initial area. All-carbon transistors, chemically synthesized by seamless integration of graphene channels and hybrid graphene/carbon nanotube electrodes, maintained structural integrity and stable electronic properties under large mechanical deformation, whereas stress-induced cracking and junction failure occurred in conventional graphene/metal transistors. Flexible, highly crumpled all-carbon transistors were further verified for in vivo recording of brain activity in rats. These results highlight the importance of advanced material and device design concepts to make improvements in neuroelectronics.

  2. Integrated Neurobiology of Bipolar Disorder

    Science.gov (United States)

    Maletic, Vladimir; Raison, Charles

    2014-01-01

    From a neurobiological perspective there is no such thing as bipolar disorder. Rather, it is almost certainly the case that many somewhat similar, but subtly different, pathological conditions produce a disease state that we currently diagnose as bipolarity. This heterogeneity – reflected in the lack of synergy between our current diagnostic schema and our rapidly advancing scientific understanding of the condition – limits attempts to articulate an integrated perspective on bipolar disorder. However, despite these challenges, scientific findings in recent years are beginning to offer a provisional “unified field theory” of the disease. This theory sees bipolar disorder as a suite of related neurodevelopmental conditions with interconnected functional abnormalities that often appear early in life and worsen over time. In addition to accelerated loss of volume in brain areas known to be essential for mood regulation and cognitive function, consistent findings have emerged at a cellular level, providing evidence that bipolar disorder is reliably associated with dysregulation of glial–neuronal interactions. Among these glial elements are microglia – the brain’s primary immune elements, which appear to be overactive in the context of bipolarity. Multiple studies now indicate that inflammation is also increased in the periphery of the body in both the depressive and manic phases of the illness, with at least some return to normality in the euthymic state. These findings are consistent with changes in the hypothalamic–pituitary–adrenal axis, which are known to drive inflammatory activation. In summary, the very fact that no single gene, pathway, or brain abnormality is likely to ever account for the condition is itself an extremely important first step in better articulating an integrated perspective on both its ontological status and pathogenesis. Whether this perspective will translate into the discovery of innumerable more homogeneous forms of

  3. Ultrasmall transistor-based light sources

    DEFF Research Database (Denmark)

    With Jensen, Per Baunegaard; Tavares, Luciana; Kjelstrup-Hansen, Jakob

    Dette projekt fokuserer på at udvikle transistor baserede nanofiber lyskilder med det overordnede mål at udvikle effektive og nano skalerede flerfarvede lyskilder integreret on-chip.......Dette projekt fokuserer på at udvikle transistor baserede nanofiber lyskilder med det overordnede mål at udvikle effektive og nano skalerede flerfarvede lyskilder integreret on-chip....

  4. Comorbid medical illness in bipolar disorder.

    Science.gov (United States)

    Forty, Liz; Ulanova, Anna; Jones, Lisa; Jones, Ian; Gordon-Smith, Katherine; Fraser, Christine; Farmer, Anne; McGuffin, Peter; Lewis, Cathryn M; Hosang, Georgina M; Rivera, Margarita; Craddock, Nick

    2014-12-01

    Individuals with a mental health disorder appear to be at increased risk of medical illness. To examine rates of medical illnesses in patients with bipolar disorder (n = 1720) and to examine the clinical course of the bipolar illness according to lifetime medical illness burden. Participants recruited within the UK were asked about the lifetime occurrence of 20 medical illnesses, interviewed using the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) and diagnosed according to DSM-IV criteria. We found significantly increased rates of several medical illnesses in our bipolar sample. A high medical illness burden was associated with a history of anxiety disorder, rapid cycling mood episodes, suicide attempts and mood episodes with a typically acute onset. Bipolar disorder is associated with high rates of medical illness. This comorbidity needs to be taken into account by services in order to improve outcomes for patients with bipolar disorder and also in research investigating the aetiology of affective disorder where shared biological pathways may play a role. Royal College of Psychiatrists.

  5. Epidemiology, neurobiology and pharmacological interventions related to suicide deaths and suicide attempts in bipolar disorder: Part I of a report of the International Society for Bipolar Disorders Task Force on Suicide in Bipolar Disorder

    Science.gov (United States)

    Schaffer, Ayal; Isometsä, Erkki T; Tondo, Leonardo; Moreno, Doris H; Sinyor, Mark; Kessing, Lars Vedel; Turecki, Gustavo; Weizman, Abraham; Azorin, Jean-Michel; Ha, Kyooseob; Reis, Catherine; Cassidy, Frederick; Goldstein, Tina; Rihmer, Zoltán; Beautrais, Annette; Chou, Yuan-Hwa; Diazgranados, Nancy; Levitt, Anthony J; Zarate, Carlos A; Yatham, Lakshmi

    2016-01-01

    Objectives Bipolar disorder is associated with elevated risk of suicide attempts and deaths. Key aims of the International Society for Bipolar Disorders Task Force on Suicide included examining the extant literature on epidemiology, neurobiology and pharmacotherapy related to suicide attempts and deaths in bipolar disorder. Methods Systematic review of studies from 1 January 1980 to 30 May 2014 examining suicide attempts or deaths in bipolar disorder, with a specific focus on the incidence and characterization of suicide attempts and deaths, genetic and non-genetic biological studies and pharmacotherapy studies specific to bipolar disorder. We conducted pooled, weighted analyses of suicide rates. Results The pooled suicide rate in bipolar disorder is 164 per 100,000 person-years (95% confidence interval = [5, 324]). Sex-specific data on suicide rates identified a 1.7:1 ratio in men compared to women. People with bipolar disorder account for 3.4–14% of all suicide deaths, with self-poisoning and hanging being the most common methods. Epidemiological studies report that 23–26% of people with bipolar disorder attempt suicide, with higher rates in clinical samples. There are numerous genetic associations with suicide attempts and deaths in bipolar disorder, but few replication studies. Data on treatment with lithium or anticonvulsants are strongly suggestive for prevention of suicide attempts and deaths, but additional data are required before relative anti-suicide effects can be confirmed. There were limited data on potential anti-suicide effects of treatment with antipsychotics or antidepressants. Conclusion This analysis identified a lower estimated suicide rate in bipolar disorder than what was previously published. Understanding the overall risk of suicide deaths and attempts, and the most common methods, are important building blocks to greater awareness and improved interventions for suicide prevention in bipolar disorder. Replication of genetic findings and

  6. Bipolar pulse generator for intense pulsed ion beam accelerator

    International Nuclear Information System (INIS)

    Ito, H.; Igawa, K.; Kitamura, I.; Masugata, K.

    2007-01-01

    A new type of pulsed ion beam accelerator named ''bipolar pulse accelerator'' (BPA) has been proposed in order to improve the purity of intense pulsed ion beams. To confirm the principle of the BPA, we developed a bipolar pulse generator for the bipolar pulse experiment, which consists of a Marx generator and a pulse forming line (PFL) with a rail gap switch on its end. In this article, we report the first experimental result of the bipolar pulse and evaluate the electrical characteristics of the bipolar pulse generator. When the bipolar pulse generator was operated at 70% of the full charge condition of the PFL, the bipolar pulse with the first (-138 kV, 72 ns) and the second pulse (+130 kV, 70 ns) was successfully obtained. The evaluation of the electrical characteristics indicates that the developed generator can produce the bipolar pulse with fast rise time and sharp reversing time

  7. Bipolar disorder diagnosis: challenges and future directions

    Science.gov (United States)

    Phillips, Mary L; Kupfer, David J

    2018-01-01

    Bipolar disorder refers to a group of affective disorders, which together are characterised by depressive and manic or hypomanic episodes. These disorders include: bipolar disorder type I (depressive and manic episodes: this disorder can be diagnosed on the basis of one manic episode); bipolar disorder type II (depressive and hypomanic episodes); cyclothymic disorder (hypomanic and depressive symptoms that do not meet criteria for depressive episodes); and bipolar disorder not otherwise specified (depressive and hypomanic-like symptoms that do not meet the diagnostic criteria for any of the aforementioned disorders). Bipolar disorder type II is especially difficult to diagnose accurately because of the difficulty in differentiation of this disorder from recurrent unipolar depression (recurrent depressive episodes) in depressed patients. The identification of objective biomarkers that represent pathophysiologic processes that differ between bipolar disorder and unipolar depression can both inform bipolar disorder diagnosis and provide biological targets for the development of new and personalised treatments. Neuroimaging studies could help the identification of biomarkers that differentiate bipolar disorder from unipolar depression, but the problem in detection of a clear boundary between these disorders suggests that they might be better represented as a continuum of affective disorders. Innovative combinations of neuroimaging and pattern recognition approaches can identify individual patterns of neural structure and function that accurately ascertain where a patient might lie on a behavioural scale. Ultimately, an integrative approach, with several biological measurements using different scales, could yield patterns of biomarkers (biosignatures) to help identify biological targets for personalised and new treatments for all affective disorders. PMID:23663952

  8. Preparation of bipolar membranes by electrospinning

    International Nuclear Information System (INIS)

    Pan, Jiefeng; Hou, Linxiao; Wang, Qiuyue; He, Yubin; Wu, Liang; Mondal, Abhishek N.; Xu, Tongwen

    2017-01-01

    A new preparative pathway for the bipolar membranes was initiated via the electrospinning and hot-press process. The prepared bipolar membrane was consisting of sulfonated poly (phenylene oxide), polyethylene glycol, and quaternized poly (phenylene oxide). The above mentioned membrane was fabricated by the continuous electrospinning of the respective layer, followed by the solvent atmosphere treatment and hot-pressing, to obtain a transparent and dense structure. The thickness of each layer can be easily tuned by controlling the electrospinning parameters. The clear interfacial structure was observed and confirmed by the scanning electron microscope. The bipolar performance is evaluated by the current–voltage curves and production yield of acid and base. The final optimized bipolar membrane had similar yield of acid and base as the casting membrane. However, extremely lower potential drop value was observed when they are applied for the production of acid and base. The experimental results showed that, electrospinning is an effective and well controlled way to fabricate bipolar membranes, in which anion or cation exchange layer as well as interfacial layer can be easily changed or added as requested. - Highlights: • Bipolar membranes were prepared through electrospinning followed by post-treatment. • As-prepared membranes were successfully applied in electrodialysis for production of acid and base. • Electrospun membranes exhibit better performance than the casting ones.

  9. Preparation of bipolar membranes by electrospinning

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Jiefeng; Hou, Linxiao; Wang, Qiuyue; He, Yubin; Wu, Liang; Mondal, Abhishek N.; Xu, Tongwen, E-mail: twxu@ustc.edu.cn

    2017-01-15

    A new preparative pathway for the bipolar membranes was initiated via the electrospinning and hot-press process. The prepared bipolar membrane was consisting of sulfonated poly (phenylene oxide), polyethylene glycol, and quaternized poly (phenylene oxide). The above mentioned membrane was fabricated by the continuous electrospinning of the respective layer, followed by the solvent atmosphere treatment and hot-pressing, to obtain a transparent and dense structure. The thickness of each layer can be easily tuned by controlling the electrospinning parameters. The clear interfacial structure was observed and confirmed by the scanning electron microscope. The bipolar performance is evaluated by the current–voltage curves and production yield of acid and base. The final optimized bipolar membrane had similar yield of acid and base as the casting membrane. However, extremely lower potential drop value was observed when they are applied for the production of acid and base. The experimental results showed that, electrospinning is an effective and well controlled way to fabricate bipolar membranes, in which anion or cation exchange layer as well as interfacial layer can be easily changed or added as requested. - Highlights: • Bipolar membranes were prepared through electrospinning followed by post-treatment. • As-prepared membranes were successfully applied in electrodialysis for production of acid and base. • Electrospun membranes exhibit better performance than the casting ones.

  10. Comorbidity bipolar disorder and personality disorders.

    Science.gov (United States)

    Latalova, Klara; Prasko, Jan; Kamaradova, Dana; Sedlackova, Jana; Ociskova, Marie

    2013-01-01

    Outcome in bipolar patients can be affected by comorbidity of other psychiatric disorders. Comorbid personality disorders are frequent and may complicate the course of bipolar illness. We have much information about treating patients with uncomplicated bipolar disorder (BD) but much less knowledge about possibilities for patients with the comorbidity of BD and personality disorder. We conducted a series of literature searches using, as key words or as items in indexed fields, bipolar disorder and personality disorder or personality traits. Articles were obtained by searching MEDLINE from 1970 to 2012. In addition, we used other papers cited in articles from these searches, or cited in articles used in our own work. Tests of personality traits indicated that euthymic bipolar patients have higher scores on harm avoidance, reward dependence, and novelty seeking than controls. Elevation of novelty seeking in bipolar patients is associated with substance abuse comorbidity. Comorbidity with personality disorders in BD patients is associated with a more difficult course of illness (such as longer episodes, shorter time euthymic, and earlier age at onset) and an increase in comorbid substance abuse, suicidality and aggression. These problems are particularly pronounced in comorbidity with borderline personality disorder. Comorbidity with antisocial personality disorder elicits a similar spectrum of difficulties; some of the antisocial behavior exhibited by patients with this comorbidity is mediated by increased impulsivity.

  11. Family environment patterns in families with bipolar children.

    Science.gov (United States)

    Belardinelli, Cecilia; Hatch, John P; Olvera, Rene L; Fonseca, Manoela; Caetano, Sheila C; Nicoletti, Mark; Pliszka, Steven; Soares, Jair C

    2008-04-01

    We studied the characteristics of family functioning in bipolar children and healthy comparison children. We hypothesized that the family environment of bipolar children would show greater levels of dysfunction as measured by the Family Environment Scale (FES). We compared the family functioning of 36 families that included a child with DSM-IV bipolar disorder versus 29 comparison families that included only healthy children. All subjects and their parents were assessed with the K-SADS-PL interview. The parents completed the FES to assess their current family functioning. Multivariate analysis of variance was used to compare the family environment of families with and without offspring with bipolar disorder. Parents of bipolar children reported lower levels of family cohesion (pfamilies where a parent had a history of mood disorders compared to families where parents had no history of mood disorders. Length of illness in the affected child was inversely associated with family cohesion (r=-0.47, p=0.004). Due to the case-control design of the study, we cannot comment on the development of these family problems or attribute their cause specifically to child bipolar disorder. Families with bipolar children show dysfunctional patterns related to interpersonal interactions and personal growth. A distressed family environment should be addressed when treating children with bipolar disorder.

  12. Bipolar Disorder and Obsessive Compulsive Disorder Comorbidity

    Directory of Open Access Journals (Sweden)

    Necla Keskin

    2014-08-01

    Full Text Available The comorbidity of bipolar disorder and anxiety disorders is a well known concept. Obsessive-compulsive disorder is the most commonly seen comorbid anxiety disorder in bipolar patients. Some genetic variants, neurotransmitters especially serotonergic systems and second-messenger systems are thought to be responsible for its etiology. Bipolar disorder alters the clinical aspects of obsessive compulsive disorder and is associated with poorer outcome. The determination of comorbidity between bipolar disorder and obsessive compulsive disorder is quite important for appropriate clinical management and treatment. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(4.000: 429-437

  13. Bipolar (spectrum) disorder and mood stabilization: standing at the crossroads?

    OpenAIRE

    De Fruyt, Jurgen; Demyttenaere, Koen

    2007-01-01

    Diagnosis and treatment of bipolar disorder has long been a neglected discipline. Recent years have shown an upsurge in bipolar research. When compared to major depressive disorder, bipolar research still remains limited and more expert based than evidence based. In bipolar diagnosis the focus is shifting from classic mania to bipolar depression and hypomania. There is a search for bipolar signatures in symptoms and course of major depressive episodes. The criteria for hypomania are softened,...

  14. The bipolar II disorder personality traits, a true syndrome?

    Science.gov (United States)

    Gudmundsson, Einar

    2015-06-01

    The author was struck by the similarities and commonality of complaints, aside from mood swings, made by Bipolar II patients and started registrating these complaints. This registrational work eventually led to the development of The Bipolar II Syndome Checklist. The aim of this work was to understand how widely the Bipolar II disorder affects the personality, and what disturbing personality traits are the most common? Deliberately, no attempt was made to diagnose psychiatric comorbidities, in the hope that one would get a clearer view of what symptoms, if any, could be considered a natural part of the Bipolar II Disorder. As far as the author knows this is a novel approach. 105 Bipolar II patients completed the Bipolar II Syndrome Checklist. The answers to the 44 questions on the list are presented in tables. Symptoms like anxiety, low self esteem, paranoia, extreme hurtfulness, migraine, Post Partum Depression, obsessive traits, alcoholism in the family are amongst the findings which will be presented in greater detail. No control group. Bipolar I patients excluded. The Bipolar II Syndrome Checklist has not been systematically validated. The results show that Bipolar II Disorder causes multiple symptoms so commonly that it may be justified to describe it as a syndrome, The Bipolar II Syndrome. Also these disturbances commonly lie in families of Bipolar II patients and are in all likelihood, greatly underdiagnosed. The clinical relevance of this study lies in increasing our knowledge and understanding of the nature of the Bipolar II Disorder, which in all probability will increase the diagnostic and treatment accuracy, since clinicians are more likely to scan for other symptoms needing treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Differential diagnosis of bipolar disorder and major depressive disorder.

    Science.gov (United States)

    Hirschfeld, R M

    2014-12-01

    Patients with bipolar disorder spend approximately half of their lives symptomatic and the majority of that time suffering from symptoms of depression, which complicates the accurate diagnosis of bipolar disorder. Challenges in the differential diagnosis of bipolar disorder and major depressive disorder are reviewed, and the clinical utility of several screening instruments is evaluated. The estimated lifetime prevalence of major depressive disorder (i.e., unipolar depression) is over 3 and one-half times that of bipolar spectrum disorders. The clinical presentation of a major depressive episode in a bipolar disorder patient does not differ substantially from that of a patient with major depressive disorder (unipolar depression). Therefore, it is not surprising that without proper screening and comprehensive evaluation many patients with bipolar disorder may be misdiagnosed with major depressive disorder (unipolar depression). In general, antidepressants have demonstrated little or no efficacy for depressive episodes associated with bipolar disorder, and treatment guidelines recommend using antidepressants only as an adjunct to mood stabilizers for patients with bipolar disorder. Thus, correct identification of bipolar disorder among patients who present with depression is critical for providing appropriate treatment and improving patient outcomes. Clinical characteristics indicative of bipolar disorder versus major depressive disorder identified in this review are based on group differences and may not apply to each individual patient. The overview of demographic and clinical characteristics provided by this review may help medical professionals distinguish between major depressive disorder and bipolar disorder. Several validated, easily administered screening instruments are available and can greatly improve the recognition of bipolar disorder in patients with depression. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. A report on older-age bipolar disorder from the International Society for Bipolar Disorders Task Force

    DEFF Research Database (Denmark)

    Sajatovic, Martha; Strejilevich, Sergio A; Gildengers, Ariel G

    2015-01-01

    , and shed light on issues of relevance to BD research across the lifespan. Although there is still a dearth of research and health efforts focused on older adults with BD, emerging data have brought some answers, innovative questions, and novel perspectives related to the notion of late onset, medical......OBJECTIVES: In the coming generation, older adults with bipolar disorder (BD) will increase in absolute numbers as well as proportion of the general population. This is the first report of the International Society for Bipolar Disorder (ISBD) Task Force on Older-Age Bipolar Disorder (OABD). METHODS...

  17. Molecular materials for organic field-effect transistors

    International Nuclear Information System (INIS)

    Mori, T

    2008-01-01

    Organic field-effect transistors are important applications of thin films of molecular materials. A variety of materials have been explored for improving the performance of organic transistors. The materials are conventionally classified as p-channel and n-channel, but not only the performance but also even the carrier polarity is greatly dependent on the combinations of organic semiconductors and electrode materials. In this review, particular emphasis is laid on multi-sulfur compounds such as tetrathiafulvalenes and metal dithiolates. These compounds are components of highly conducting materials such as organic superconductors, but are also used in organic transistors. The charge-transfer complexes are used in organic transistors as active layers as well as electrodes. (topical review)

  18. Multiple-channel detection of cellular activities by ion-sensitive transistors

    Science.gov (United States)

    Machida, Satoru; Shimada, Hideto; Motoyama, Yumi

    2018-04-01

    An ion-sensitive field-effect transistor to record cellular activities was demonstrated. This field-effect transistor (bio transistor) includes cultured cells on the gate insulator instead of gate electrode. The bio transistor converts a change in potential underneath the cells into variation of the drain current when ion channels open. The bio transistor has high detection sensitivity to even minute variations in potential utilizing a subthreshold swing region. To open ion channels, a reagent solution (acetylcholine) was added to a human-originating cell cultured on the bio transistor. The drain current was successfully decreased with the addition of acetylcholine. Moreover, we attempted to detect the opening of ion channels using a multiple-channel measurement circuit containing several bio transistors. As a consequence, the drain current distinctly decreased only after the addition of acetylcholine. We confirmed that this measurement system including bio transistors enables to observation of cellular activities sensitively and simultaneously.

  19. On Bipolar Valued Fuzzy k-Ideals in Hermirings

    International Nuclear Information System (INIS)

    Mahmood, T.; Ejaz, A.

    2015-01-01

    In this paper we discuss some results associated with bipolar valued fuzzy k -ideals of hermirings. We also define bipolar valued fuzzy k-intrinsic product and characterize k-hemiregular hermirings by using their bipolar valued fuzzy k -ideals. (author)

  20. Exercising control over bipolar disorder.

    Science.gov (United States)

    Malhi, Gin S; Byrow, Yulisha

    2016-11-01

    Following extensive research exercise has emerged as an effective treatment for major depressive disorder, and it is now a recognised therapy alongside other interventions. In contrast, there is a paucity of research examining the therapeutic effects of exercise for those with bipolar disorder. Given that dysfunctional reward processing is central to bipolar disorder, research suggests that exercise can perhaps be framed as a reward-related event that may have the potential to precipitate a manic episode. The behavioural activation system (BAS) is a neurobehavioural system that is associated with responding to reward and provides an appropriate framework to theoretically examine and better understand the effects of exercise treatment on bipolar disorder. This article discusses recent research findings and provides an overview of the extant literature related to the neurobiological underpinnings of BAS and exercise as they relate to bipolar disorder. This is important clinically because depending on mood state in bipolar disorder, we postulate that exercise could be either beneficial or deleterious with positive or negative effects on the illness. Clearly, this complicates the evaluation of exercise as a potential treatment in terms of identifying its optimal characteristics in this population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  1. Photon-gated spin transistor

    OpenAIRE

    Li, Fan; Song, Cheng; Cui, Bin; Peng, Jingjing; Gu, Youdi; Wang, Guangyue; Pan, Feng

    2017-01-01

    Spin-polarized field-effect transistor (spin-FET), where a dielectric layer is generally employed for the electrical gating as the traditional FET, stands out as a seminal spintronic device under the miniaturization trend of electronics. It would be fundamentally transformative if optical gating was used for spin-FET. We report a new type of spin-polarized field-effect transistor (spin-FET) with optical gating, which is fabricated by partial exposure of the (La,Sr)MnO3 channel to light-emitti...

  2. Organic Thin-Film Transistor (OTFT-Based Sensors

    Directory of Open Access Journals (Sweden)

    Daniel Elkington

    2014-04-01

    Full Text Available Organic thin film transistors have been a popular research topic in recent decades and have found applications from flexible displays to disposable sensors. In this review, we present an overview of some notable articles reporting sensing applications for organic transistors with a focus on the most recent publications. In particular, we concentrate on three main types of organic transistor-based sensors: biosensors, pressure sensors and “e-nose”/vapour sensors.

  3. Doped organic transistors operating in the inversion and depletion regime

    Science.gov (United States)

    Lüssem, Björn; Tietze, Max L.; Kleemann, Hans; Hoßbach, Christoph; Bartha, Johann W.; Zakhidov, Alexander; Leo, Karl

    2013-01-01

    The inversion field-effect transistor is the basic device of modern microelectronics and is nowadays used more than a billion times on every state-of-the-art computer chip. In the future, this rigid technology will be complemented by flexible electronics produced at extremely low cost. Organic field-effect transistors have the potential to be the basic device for flexible electronics, but still need much improvement. In particular, despite more than 20 years of research, organic inversion mode transistors have not been reported so far. Here we discuss the first realization of organic inversion transistors and the optimization of organic depletion transistors by our organic doping technology. We show that the transistor parameters—in particular, the threshold voltage and the ON/OFF ratio—can be controlled by the doping concentration and the thickness of the transistor channel. Injection of minority carriers into the doped transistor channel is achieved by doped contacts, which allows forming an inversion layer. PMID:24225722

  4. [Circadian markers and genes in bipolar disorder].

    Science.gov (United States)

    Yeim, S; Boudebesse, C; Etain, B; Belliviera, F

    2015-09-01

    Bipolar disorder is a severe and complex multifactorial disease, characterized by alternance of acute episodes of depression and mania/hypomania, interspaced by euthymic periods. The etiological determinants of bipolar disorder yet, are still poorly understood. For the last 30 years, chronobiology is an important field of investigation to better understand the pathophysiology of bipolar disorder. We conducted a review using Medline, ISI Database, EMBase, PsyInfo up to January 2015, using the following keywords combinations: "mood disorder", "bipolar disorder", "depression", "unipolar disorder", "major depressive disorder", "affective disorder", for psychiatric conditions; and "circadian rhythms", "circadian markers", "circadian gene", "clock gene", "melatonin" for circadian rhythms. The search critera was presence of word in any field of the article. Quantitative and qualitative circadian abnormalities are associated with bipolar disorders both during acute episodes and euthymic periods, suggesting that these altered circadian rhythms may represent biological trait markers of the disorder. These circadian dysfunctions were assessed by various validated tools including polysomnography, actigraphy, sleep diaries, chronotype assessments and blood melatonin/cortisol measures. Other altered endogenous circadian activities have also been reported in bipolar patients, such as hormones secretion, core body temperature or fibroblasts activity. Moreover, these markers were also altered in healthy relatives of bipolar patients, suggesting a degree of heritability. Several genetic association studies have also showed associations between multiple circadian genes and bipolar disorder, such as CLOCK, ARTNL1, GSK3β, PER3, NPAS2, NR1D1, TIMELESS, RORA, RORB, and CSNK1ε. Thus, these circadian gene variants may contribute to the genetic susceptibility of the disease. Furthermore, the study of the clock system may help to better understand some phenotypic aspects like the

  5. New types of bipolar fuzzy sets in -semihypergroups

    Directory of Open Access Journals (Sweden)

    Naveed Yaqoob

    2016-04-01

    Full Text Available The notion of bipolar fuzzy set was initiated by Lee (2000 as a generalization of the notion fuzzy sets and intuitionistic fuzzy sets, which have drawn attention of many mathematicians and computer scientists. In this paper, we initiate a study on bipolar ( , -fuzzy sets in -semihypergroups. By using the concept of bipolar ( , -fuzzy sets (Yaqoob and Ansari, 2013, we introduce the notion of bipolar ( , -fuzzy sub -semihypergroups (-hyperideals and bi--hyperideals and discuss some basic results on bipolar ( , -fuzzy sets in -semihypergroups. Furthermore, we define the bipolar fuzzy subset ,               and prove that if  ,       is a bipolar ( , -fuzzy sub -semihypergroup (resp., -hyperideal and bi--hyperideal of H; then ,               is also a bipolar ( , -fuzzy sub -semihypergroup (resp., -hyperideal and bi--hyperideal of H.

  6. Classification of cognitive performance in bipolar disorder.

    Science.gov (United States)

    Sparding, Timea; Silander, Katja; Pålsson, Erik; Östlind, Josefin; Ekman, Carl Johan; Sellgren, Carl M; Joas, Erik; Hansen, Stefan; Landén, Mikael

    2017-09-01

    To understand the etiology of cognitive impairment associated with bipolar disorder, we need to clarify potential heterogeneity in cognitive functioning. To this end, we used multivariate techniques to study if the correlation structure of cognitive abilities differs between persons with bipolar disorder and controls. Clinically stable patients with bipolar disorder (type I: n = 64; type II: n = 44) and healthy controls (n = 86) were assessed with a wide range of cognitive tests measuring executive function, speed, memory, and verbal skills. Data were analysed with multivariate techniques. A distinct subgroup (∼30%) could be identified that performed significantly poorer on tests concerning memory function. This cognitive phenotype subgroup did not differ from the majority of bipolar disorder patients with respect to other demographic or clinical characteristics. Whereas the majority of patients performed similar to controls, a subgroup of patients with bipolar disorder differed substantially from healthy controls in the correlation pattern of low-level cognitive abilities. This suggests that cognitive impairment is not a general trait in bipolar disorder but characteristic of a cognitive subgroup. This has important clinical implications for cognitive rehabilitation and remediation.

  7. Implementation of Self-Bias Transistor on Voting Logic

    International Nuclear Information System (INIS)

    Harzawardi Hasim; Syirrazie Che Soh

    2014-01-01

    Study in the eld of digital integrated circuit (IC) already become common to the modern industrial. Day by day we have been introduced with new gadget that was developed based on transistor. This paper will study the implementation of self-bias transistor on voting logic. The self-bias transistor will connected both on pull-up network and pull-down network. On previous research, study on comparison of total number of transistors, time propagation delay, and frequency between NAND and NOR gate of voting logic. It's show, with the same number of transistor, NAND gate achieve high frequency and low time propagation delay compare to NOR gate. We extend this analysis by comparing the total number of transistor, time propagation delay, frequency and power dissipation between common NAND gate with self-bias NAND gate. Extensive LTSpice simulations were performed using IBM 90 nm CMOS(Complementary Metal Oxide Semiconductor) process technology. The result show self-bias voting NAND gate consumes 54 % less power dissipation, 43% slow frequency and 43 % high time propagation delay compare to common voting NAND gate. (author)

  8. [Bipolar disorders and anorexia nervosa: A clinical study].

    Science.gov (United States)

    Valentin, M; Radon, L; Duclos, J; Curt, F; Godart, N

    2018-06-20

    Anorexia nervosa is often accompanied by comorbid mood disorders, in particular depression, but individual or family history of bipolar disorders has not frequently been explored in anorexia nervosa. The objectives of the present study were: (1) to assess the frequency of bipolar disorders in patients with anorexia nervosa hospitalized in adolescence and in their parents, (2) to determine whether the patients with a personal or family history of bipolar disorders present particular characteristics in the way in which anorexia nervosa manifests itself, in their medical history, in the secondary diagnoses established, and in the treatments prescribed. Overall, 97 female patients aged 13 to 20 hospitalized for anorexia nervosa and their parents were assessed. The diagnoses of anorexia nervosa and bipolar disorders were established on the basis of DSM-IV-TR criteria. A high frequency of type II and type V bipolar disorders was observed. The patients with anorexia nervosa and presenting personal or family histories of bipolar disorder had an earlier onset of anorexia nervosa, more numerous hospitalizations, a longer time-lapse between anorexia nervosa onset and hospitalization, more suicide attempts and more psychiatric comorbidities. The occurrence of anorexia nervosa-bipolar disorders comorbidity appears to be considerable and linked to the severity of anorexia nervosa, raising the issue of the relationship between anorexia nervosa and bipolar disorders. Copyright © 2017. Published by Elsevier Masson SAS.

  9. Social support and bipolar disorder

    Directory of Open Access Journals (Sweden)

    Paula Mendonça Studart

    2015-08-01

    Full Text Available Background Bipolar disorder is a chronic condition that affects the functioning of its carriers in many different ways, even when treated properly. Therefore, it’s also important to identify the psychosocial aspects that could contribute to an improvement of this population’s quality of life.Objective Carry out a literature review on the role of social support in cases of bipolar disorder.Method A research on the following online databases PubMed, Lilacs and SciELO was conducted by using the keywords “social support” or “social networks” and “mood disorders” or “bipolar disorder” or “affective disorder,” with no defined timeline.Results Only 13 studies concerning the topic of social support and BD were found in the search for related articles. Generally speaking, the results show low rates of social support for BD patients.Discussion Despite the growing interest in the overall functioning of patients with bipolar disorder, studies on social support are still rare. Besides, the existing studies on the subject use different methodologies, making it difficult to establish data comparisons.

  10. CMOS-based carbon nanotube pass-transistor logic integrated circuits

    Science.gov (United States)

    Ding, Li; Zhang, Zhiyong; Liang, Shibo; Pei, Tian; Wang, Sheng; Li, Yan; Zhou, Weiwei; Liu, Jie; Peng, Lian-Mao

    2012-01-01

    Field-effect transistors based on carbon nanotubes have been shown to be faster and less energy consuming than their silicon counterparts. However, ensuring these advantages are maintained for integrated circuits is a challenge. Here we demonstrate that a significant reduction in the use of field-effect transistors can be achieved by constructing carbon nanotube-based integrated circuits based on a pass-transistor logic configuration, rather than a complementary metal-oxide semiconductor configuration. Logic gates are constructed on individual carbon nanotubes via a doping-free approach and with a single power supply at voltages as low as 0.4 V. The pass-transistor logic configurarion provides a significant simplification of the carbon nanotube-based circuit design, a higher potential circuit speed and a significant reduction in power consumption. In particular, a full adder, which requires a total of 28 field-effect transistors to construct in the usual complementary metal-oxide semiconductor circuit, uses only three pairs of n- and p-field-effect transistors in the pass-transistor logic configuration. PMID:22334080

  11. Bipolar disorder and dementia: where is the link?

    Science.gov (United States)

    Masouy, Anaïs; Chopard, Gilles; Vandel, Pierre; Magnin, Eloi; Rumbach, Lucien; Sechter, Daniel; Haffen, Emmanuel

    2011-03-01

    Cognitive disorders appearing in the course of bipolar disease have been identified, and recent studies have defined the neuropsychological characteristics of this pathology, which includes attention, executive function, memory and language disorders. However, questions remain concerning the appearance of dementia symptoms over the course of bipolar disorder in certain patients: is it a chance association or is there a connection between bipolar disorders and dementia? If the latter hypothesis is considered, what is the nature of the dementia, which might be considered as a dementia specific to bipolar disorder? Current clinical, neuropsychological and cerebral imaging data are inconclusive, but similarities with frontotemporal dementia might be highlighted. Functional imaging studies might provide answers as well as more specific tests in neuropsychology. The cause of cognitive damage in bipolar disease also raises questions concerning a neurodevelopmental or neurodegenerative process, because several factors seem to influence cognition and these two processes might occur simultaneously. Long-term studies are necessary to determine whether cognitive deterioration in bipolar disease is stable or progressive. There might also be different neurobiological subgroups of patients with bipolar disease. © 2011 The Authors. Psychogeriatrics © 2011 Japanese Psychogeriatric Society.

  12. Efficient simulation of power MOS transistors

    NARCIS (Netherlands)

    Ugryumova, M.; Schilders, W.H.A.

    2011-01-01

    In this report we present a few industrial problems related to modeling of MOS transistors. We suggest an efficient algorithm for computing output current at the top ports of power MOS transistors for given voltage excitations. The suggested algorithm exploits the connection between the resistor and

  13. Thermal transistor utilizing gas-liquid transition

    KAUST Repository

    Komatsu, Teruhisa S.

    2011-01-25

    We propose a simple thermal transistor, a device to control heat current. In order to effectively change the current, we utilize the gas-liquid transition of the heat-conducting medium (fluid) because the gas region can act as a good thermal insulator. The three terminals of the transistor are located at both ends and the center of the system, and are put into contact with distinct heat baths. The key idea is a special arrangement of the three terminals. The temperature at one end (the gate temperature) is used as an input signal to control the heat current between the center (source, hot) and another end (drain, cold). Simulating the nanoscale systems of this transistor, control of heat current is demonstrated. The heat current is effectively cut off when the gate temperature is cold and it flows normally when it is hot. By using an extended version of this transistor, we also simulate a primitive application for an inverter. © 2011 American Physical Society.

  14. Water-gel for gating graphene transistors.

    Science.gov (United States)

    Kim, Beom Joon; Um, Soong Ho; Song, Woo Chul; Kim, Yong Ho; Kang, Moon Sung; Cho, Jeong Ho

    2014-05-14

    Water, the primary electrolyte in biology, attracts significant interest as an electrolyte-type dielectric material for transistors compatible with biological systems. Unfortunately, the fluidic nature and low ionic conductivity of water prevents its practical usage in such applications. Here, we describe the development of a solid state, megahertz-operating, water-based gate dielectric system for operating graphene transistors. The new electrolyte systems were prepared by dissolving metal-substituted DNA polyelectrolytes into water. The addition of these biocompatible polyelectrolytes induced hydrogelation to provide solid-state integrity to the system. They also enhanced the ionic conductivities of the electrolytes, which in turn led to the quick formation of an electric double layer at the graphene/electrolyte interface that is beneficial for modulating currents in graphene transistors at high frequencies. At the optimized conditions, the Na-DNA water-gel-gated flexible transistors and inverters were operated at frequencies above 1 MHz and 100 kHz, respectively.

  15. Paired structures and bipolar knowledge representation

    DEFF Research Database (Denmark)

    Montero, Javier; Bustince, Humberto; Franco, Camilo

    In this strictly positional paper we propose a general approach to bipolar knowledge representation, where the meaning of concepts can be modelled by examining their decomposition into opposite and neutral categories. In particular, it is the semantic relationship between the opposite categories...... and at the same time the type of neutrality rising in between opposites. Based on this first level of bipolar knowledge representation, paired structures in fact offer the means to characterize a specific bipolar valuation scale depending on the meaning of the concept that has to be verified. In this sense...

  16. Toward a complex system understanding of bipolar disorder: A chaotic model of abnormal circadian activity rhythms in euthymic bipolar disorder.

    Science.gov (United States)

    Hadaeghi, Fatemeh; Hashemi Golpayegani, Mohammad Reza; Jafari, Sajad; Murray, Greg

    2016-08-01

    In the absence of a comprehensive neural model to explain the underlying mechanisms of disturbed circadian function in bipolar disorder, mathematical modeling is a helpful tool. Here, circadian activity as a response to exogenous daily cycles is proposed to be the product of interactions between neuronal networks in cortical (cognitive processing) and subcortical (pacemaker) areas of the brain. To investigate the dynamical aspects of the link between disturbed circadian activity rhythms and abnormalities of neurotransmitter functioning in frontal areas of the brain, we developed a novel mathematical model of a chaotic system which represents fluctuations in circadian activity in bipolar disorder as changes in the model's parameters. A novel map-based chaotic system was developed to capture disturbances in circadian activity across the two extreme mood states of bipolar disorder. The model uses chaos theory to characterize interplay between neurotransmitter functions and rhythm generation; it aims to illuminate key activity phenomenology in bipolar disorder, including prolonged sleep intervals, decreased total activity and attenuated amplitude of the diurnal activity rhythm. To test our new cortical-circadian mathematical model of bipolar disorder, we utilized previously collected locomotor activity data recorded from normal subjects and bipolar patients by wrist-worn actigraphs. All control parameters in the proposed model have an important role in replicating the different aspects of circadian activity rhythm generation in the brain. The model can successfully replicate deviations in sleep/wake time intervals corresponding to manic and depressive episodes of bipolar disorder, in which one of the excitatory or inhibitory pathways is abnormally dominant. Although neuroimaging research has strongly implicated a reciprocal interaction between cortical and subcortical regions as pathogenic in bipolar disorder, this is the first model to mathematically represent this

  17. Bipolar electrochemistry.

    Science.gov (United States)

    Fosdick, Stephen E; Knust, Kyle N; Scida, Karen; Crooks, Richard M

    2013-09-27

    A bipolar electrode (BPE) is an electrically conductive material that promotes electrochemical reactions at its extremities (poles) even in the absence of a direct ohmic contact. More specifically, when sufficient voltage is applied to an electrolyte solution in which a BPE is immersed, the potential difference between the BPE and the solution drives oxidation and reduction reactions. Because no direct electrical connection is required to activate redox reactions, large arrays of electrodes can be controlled with just a single DC power supply or even a battery. The wireless aspect of BPEs also makes it possible to electrosynthesize and screen novel materials for a wide variety of applications. Finally, bipolar electrochemistry enables mobile electrodes, dubbed microswimmers, that are able to move freely in solution. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Cognitive behavioral therapy for bipolar disorders

    OpenAIRE

    Lotufo Neto, Francisco

    2004-01-01

    Descrição dos objetivos e principais técnicas da terapia comportamental cognitiva usadas para a psicoterapia das pessoas com transtorno bipolar.Objectives and main techniques of cognitive behavior therapy for the treatment of bipolar disorder patients are described.

  19. Biological dysrhythm in remitted bipolar I disorder.

    Science.gov (United States)

    Iyer, Aishwarya; Palaniappan, Pradeep

    2017-12-01

    Recent treatment guidelines support treatment of biological rhythm abnormalities as a part of treatment of bipolar disorder, but still, literature examining various domains (Sleep, Activity, Social, and Eating) of biological rhythm and its clinical predictors are less. The main aim of our study is to compare various domains of biological rhythm among remitted bipolar I subjects and healthy controls. We also explored for any association between clinical variables and biological rhythm among bipolar subjects. 40 subjects with Bipolar I disorder and 40 healthy controls who met inclusion and exclusion criteria were recruited for the study. Diagnoses were ascertained by a qualified psychiatrist using MINI 5.0. Sociodemographic details, biological rhythm (BRIAN-Biological Rhythm Interview of assessment in Neuropsychiatry) and Sleep functioning (PSQI- Pittsburgh Sleep Quality Index) were assessed in all subjects. Mean age of the Bipolar subjects and controls were 41.25±11.84years and 38.25±11.25 years respectively. Bipolar subjects experienced more biological rhythm disturbance when compared to healthy controls (total BRIAN score being 34.25±9.36 vs 28.2±6.53) (p=0.002). Subsyndromal depressive symptoms (HDRS) had significant positive correlation with BRIAN global scores(r=0.368, p=0.02). Linear regression analysis showed that number of episodes which required hospitalization (β=0.601, t=3.106, P=0.004), PSQI (β=0.394, t=2.609, p=0.014), HDRS (β=0.376, t=2.34, t=0.036) explained 31% of variance in BRIAN scores in remitted bipolar subjects. Biological rhythm disturbances seem to persist even after clinical remission of bipolar illness. More studies to look into the impact of subsyndromal depressive symptoms on biological rhythm are needed. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Transistor reset preamplifier for high-rate high-resolution spectroscopy

    International Nuclear Information System (INIS)

    Landis, D.A.; Cork, C.P.; Madden, N.W.; Goulding, F.S.

    1981-10-01

    Pulsed transistor reset of high resolution charge sensitive preamplifiers used in cooled semiconductor spectrometers can sometimes have an advantage over pulsed light reset systems. Several versions of transistor reset spectrometers using both silicon and germanium detectors have been built. This paper discusses the advantages of the transistor reset system and illustrates several configurations of the packages used for the FET and reset transistor. It also describes the preamplifer circuit and shows the performance of the spectrometer at high rates

  1. Protonic transistors from thin reflecting films

    Energy Technology Data Exchange (ETDEWEB)

    Ordinario, David D.; Phan, Long; Jocson, Jonah-Micah [Department of Chemical Engineering and Materials Science, University of California, Irvine, California 92697 (United States); Nguyen, Tam [Department of Chemistry, University of California, Irvine, California 92697 (United States); Gorodetsky, Alon A., E-mail: alon.gorodetsky@uci.edu [Department of Chemical Engineering and Materials Science, University of California, Irvine, California 92697 (United States); Department of Chemistry, University of California, Irvine, California 92697 (United States)

    2015-01-01

    Ionic transistors from organic and biological materials hold great promise for bioelectronics applications. Thus, much research effort has focused on optimizing the performance of these devices. Herein, we experimentally validate a straightforward strategy for enhancing the high to low current ratios of protein-based protonic transistors. Upon reducing the thickness of the transistors’ active layers, we increase their high to low current ratios 2-fold while leaving the other figures of merit unchanged. The measured ratio of 3.3 is comparable to the best values found for analogous devices. These findings underscore the importance of the active layer geometry for optimum protonic transistor functionality.

  2. Coping and personality in older patients with bipolar disorder.

    Science.gov (United States)

    Schouws, Sigfried N T M; Paans, Nadine P G; Comijs, Hannie C; Dols, Annemiek; Stek, Max L

    2015-09-15

    Little is known about coping styles and personality traits in older bipolar patients. Adult bipolar patients show a passive coping style and higher neuroticism scores compared to the general population. Our aim is to investigate personality traits and coping in older bipolar patients and the relationship between coping and personality. 75 Older patients (age > 60) with bipolar I or II disorder in a euthymic mood completed the Utrecht Coping List and the NEO Personality Inventory FFI and were compared to normative data. Older bipolar patients show more passive coping styles compared to healthy elderly. Their personality traits are predominated by openness, in contrast conscientiousness and altruism are relatively sparse. Neuroticism was related to passive coping styles, whereas conscientiousness was related to an active coping style. Older bipolar patients have more passive coping styles. Their personality is characterized by openness and relatively low conscientiousness and altruism. Our sample represents a survival cohort; this may explain the differences in personality traits between older patients in this study and in adult bipolar patients in other studies. The association between coping styles and personality traits is comparable to reports of younger adult patients with bipolar disorder. Longitudinal studies are warranted to explore if coping and personality change with ageing in bipolar patients and to determine which coping style is most effective in preventing mood episodes. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. The role of sleep in bipolar disorder

    Directory of Open Access Journals (Sweden)

    Gold AK

    2016-06-01

    Full Text Available Alexandra K Gold,1 Louisa G Sylvia,1,2 1Department of Psychiatry, Massachusetts General Hospital, 2Harvard Medical School, Boston, MA, USA Abstract: Bipolar disorder is a serious mental illness characterized by alternating periods of elevated and depressed mood. Sleep disturbances in bipolar disorder are present during all stages of the condition and exert a negative impact on overall course, quality of life, and treatment outcomes. We examine the partnership between circadian system (process C functioning and sleep–wake homeostasis (process S on optimal sleep functioning and explore the role of disruptions in both systems on sleep disturbances in bipolar disorder. A convergence of evidence suggests that sleep problems in bipolar disorder result from dysregulation across both process C and process S systems. Biomarkers of depressive episodes include heightened fragmentation of rapid eye movement (REM sleep, reduced REM latency, increased REM density, and a greater percentage of awakenings, while biomarkers of manic episodes include reduced REM latency, greater percentage of stage I sleep, increased REM density, discontinuous sleep patterns, shortened total sleep time, and a greater time awake in bed. These findings highlight the importance of targeting novel treatments for sleep disturbance in bipolar disorder. Keywords: bipolar disorder, circadian rhythms, sleep–wake homeostasis

  4. High mobility and quantum well transistors design and TCAD simulation

    CERN Document Server

    Hellings, Geert

    2013-01-01

    For many decades, the semiconductor industry has miniaturized transistors, delivering increased computing power to consumers at decreased cost. However, mere transistor downsizing does no longer provide the same improvements. One interesting option to further improve transistor characteristics is to use high mobility materials such as germanium and III-V materials. However, transistors have to be redesigned in order to fully benefit from these alternative materials. High Mobility and Quantum Well Transistors: Design and TCAD Simulation investigates planar bulk Germanium pFET technology in chapters 2-4, focusing on both the fabrication of such a technology and on the process and electrical TCAD simulation. Furthermore, this book shows that Quantum Well based transistors can leverage the benefits of these alternative materials, since they confine the charge carriers to the high-mobility material using a heterostructure. The design and fabrication of one particular transistor structure - the SiGe Implant-Free Qu...

  5. Climatic factors and bipolar affective disorder

    DEFF Research Database (Denmark)

    Christensen, Ellen Margrethe; Larsen, Jens Knud; Gjerris, Annette

    2008-01-01

    In bipolar disorder, the factors provoking a new episode are unknown. As a seasonal variation has been noticed, it has been suggested that weather conditions may play a role. The aim of the study was to elucidate whether meteorological parameters influence the development of new bipolar phases....... A group of patients with at least three previous hospitalizations for bipolar disorder was examined every 3 months for up to 3 years. At each examination an evaluation of the affective phase was made according to the Hamilton Depression Scale (HAM-D(17)), and the Bech-Rafaelsen Mania Rating Scale (MAS......). In the same period, daily recordings from the Danish Meteorological Institute were received. We found no correlations between onset of bipolar episodes [defined as MAS score of 11 or more (mania) and as HAM-D(17) score of 12 or more (depression)] and any meteorological parameters. We found a statistical...

  6. HIV-infected persons with bipolar disorder are less aware of memory deficits than HIV-infected persons without bipolar disorder

    OpenAIRE

    Blackstone, K; Tobin, A; Posada, C; Gouaux, B; Grant, I; Moore, DJ

    2012-01-01

    Episodic memory deficits are common in HIV infection and bipolar disorder, but patient insight into such deficits remains unclear. Thirty-four HIV-infected individuals without bipolar disorder (HIV+/BD-) and 47 HIV+ individuals with comorbid bipolar disorder (HIV+/BD+) were administered the Hopkins Verbal Learning Test-Revised and the Brief Visuospatial Memory Test-Revised to examine objective learning/memory functioning. Subjective memory complaints were assessed via the memory s ubscale of ...

  7. I–V, C–V and deep level transient spectroscopy study of 24 MeV ...

    Indian Academy of Sciences (India)

    This paper describes the effect of 24 MeV proton irradiation on the electrical characteristics of a pnp bipolar junction transistor 2N 2905A. –, – and DLTS measurements are carried out to characterize the transistor before and after irradiation. The properties of deep level defects observed in the bulk of the transistor are ...

  8. Ultrashort Channel Length Black Phosphorus Field-Effect Transistors.

    Science.gov (United States)

    Miao, Jinshui; Zhang, Suoming; Cai, Le; Scherr, Martin; Wang, Chuan

    2015-09-22

    This paper reports high-performance top-gated black phosphorus (BP) field-effect transistors with channel lengths down to 20 nm fabricated using a facile angle evaporation process. By controlling the evaporation angle, the channel length of the transistors can be reproducibly controlled to be anywhere between 20 and 70 nm. The as-fabricated 20 nm top-gated BP transistors exhibit respectable on-state current (174 μA/μm) and transconductance (70 μS/μm) at a VDS of 0.1 V. Due to the use of two-dimensional BP as the channel material, the transistors exhibit relatively small short channel effects, preserving a decent on-off current ratio of 10(2) even at an extremely small channel length of 20 nm. Additionally, unlike the unencapsulated BP devices, which are known to be chemically unstable in ambient conditions, the top-gated BP transistors passivated by the Al2O3 gate dielectric layer remain stable without noticeable degradation in device performance after being stored in ambient conditions for more than 1 week. This work demonstrates the great promise of atomically thin BP for applications in ultimately scaled transistors.

  9. Suicide attempts and clinical features of bipolar patients.

    Science.gov (United States)

    Berkol, Tonguç D; İslam, Serkan; Kırlı, Ebru; Pınarbaşı, Rasim; Özyıldırım, İlker

    2016-06-01

    To identify clinical predictors of suicide attempts in patients with bipolar disorder. This study included bipolar patients who were treated in the Psychiatry Department, Haseki Training and Research Hospital, Istanbul, Turkey, between 2013 and 2014; an informed consent was obtained from the participants. Two  hundred and eighteen bipolar patients were assessed by using the structured clinical interview for Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) Axis-I (SCID-I) in order to detect all possible psychiatric comorbid diagnoses. Clinical predictors of suicide attempts were examined in attempters and non-attempters. The study design was retrospective. The lifetime suicide attempt rate for the entire sample was 19.2%. Suicide attempters with bipolar disorder had more lifetime comorbidity of eating disorder. Female gender and family history of mood disorder were significant predictors for suicide attempts. There was no difference between groups in terms of bipolar disorder subtype, onset age of bipolar disorder, total number of episodes, first and predominant episode type, suicide history in first degree relatives, severity of episodes, and hospitalization and being psychotic. Our study revealed that female gender, family history of mood disorder, and eating disorder are more frequent in bipolar patients with at least one suicide attempt.

  10. Perceived parental rearing of bipolar offspring

    NARCIS (Netherlands)

    Reichart, C. G.; van der Ende, J.; Hillegers, M. H. J.; Wals, M.; Bongers, I. L.; Nolen, W. A.; Ormel, J.; Verhulst, F. C.

    Objective: To explore the impact of growing up with a parent with a bipolar disorder. First, we compared parental rearing behavior perceived by young adult offspring of bipolar parents with parental rearing behavior perceived by same aged young adults from the general population. Secondly, we

  11. Combinations of genetic variants associated with bipolar disorder

    DEFF Research Database (Denmark)

    Mellerup, Erling; Andreassen, Ole A; Bennike, Bente

    2017-01-01

    The main objective of the study was to find genetic variants that in combination are significantly associated with bipolar disorder. In previous studies of bipolar disorder, combinations of three and four single nucleotide polymorphisms (SNP) genotypes taken from 803 SNPs were analyzed, and five...... clusters of combinations were found to be significantly associated with bipolar disorder. In the present study, combinations of ten SNP genotypes taken from the same 803 SNPs were analyzed, and one cluster of combinations was found to be significantly associated with bipolar disorder. Combinations from......, heterozygote or variant homozygote. In the combinations containing 10 SNP genotypes almost all the genotypes were the normal homozygote. Such a finding may indicate that accumulation in the genome of combinations containing few SNP genotypes may be a risk factor for bipolar disorder when those combinations...

  12. Bipolar magnetic semiconductor in silicene nanoribbons

    International Nuclear Information System (INIS)

    Farghadan, Rouhollah

    2017-01-01

    Highlights: • A new electronic phase for silicene nanoribbon in the presence of electric and magnetic fields. • Bipolar magnetic semiconductor with controllable spin-flip and spin-conserved gaps in silicene. • Robust bipolar magnetic semiconductor features in a rough silicene. • Perfect and reversible spin polarization in silicene nanoribbon junctions. - Abstract: A theoretical study was presented on generation of spin polarization in silicene nanoribbons using the single-band tight-binding approximation and the non-equilibrium Green’s function formalism. We focused on the effect of electric and exchange magnetic fields on the spin-filter capabilities of zigzag-edge silicene nanoribbons in the presence of the intrinsic spin-orbit interaction. The results show that a robust bipolar magnetic semiconductor with controllable spin-flip and spin-conserved gaps can be obtained when exchange magnetic and electric field strengths are both larger than the intrinsic spin-orbit interaction. Therefore, zigzag silicene nanoribbons could act as bipolar and perfect spin filter devices with a large spin-polarized current and a reversible spin polarization in the vicinity of the Fermi energy. We also investigated the effect of edge roughness and found that the bipolar magnetic semiconductor features are robust against edge disorder in silicene nanoribbon junctions. These results may be useful in multifunctional spin devices based on silicene nanoribbons.

  13. Bipolar magnetic semiconductor in silicene nanoribbons

    Energy Technology Data Exchange (ETDEWEB)

    Farghadan, Rouhollah, E-mail: rfarghadan@kashanu.ac.ir

    2017-08-01

    Highlights: • A new electronic phase for silicene nanoribbon in the presence of electric and magnetic fields. • Bipolar magnetic semiconductor with controllable spin-flip and spin-conserved gaps in silicene. • Robust bipolar magnetic semiconductor features in a rough silicene. • Perfect and reversible spin polarization in silicene nanoribbon junctions. - Abstract: A theoretical study was presented on generation of spin polarization in silicene nanoribbons using the single-band tight-binding approximation and the non-equilibrium Green’s function formalism. We focused on the effect of electric and exchange magnetic fields on the spin-filter capabilities of zigzag-edge silicene nanoribbons in the presence of the intrinsic spin-orbit interaction. The results show that a robust bipolar magnetic semiconductor with controllable spin-flip and spin-conserved gaps can be obtained when exchange magnetic and electric field strengths are both larger than the intrinsic spin-orbit interaction. Therefore, zigzag silicene nanoribbons could act as bipolar and perfect spin filter devices with a large spin-polarized current and a reversible spin polarization in the vicinity of the Fermi energy. We also investigated the effect of edge roughness and found that the bipolar magnetic semiconductor features are robust against edge disorder in silicene nanoribbon junctions. These results may be useful in multifunctional spin devices based on silicene nanoribbons.

  14. Personality disorder symptom severity predicts onset of mood episodes and conversion to bipolar I disorder in individuals with bipolar spectrum disorder.

    Science.gov (United States)

    Ng, Tommy H; Burke, Taylor A; Stange, Jonathan P; Walshaw, Patricia D; Weiss, Rachel B; Urosevic, Snezana; Abramson, Lyn Y; Alloy, Lauren B

    2017-04-01

    Although personality disorders (PDs) are highly comorbid with bipolar spectrum disorders (BSDs), little longitudinal research has been conducted to examine the prospective impact of PD symptoms on the course of BSDs. The aim of this study is to examine whether PD symptom severity predicts shorter time to onset of bipolar mood episodes and conversion to bipolar I disorder over time among individuals with less severe BSDs. Participants (n = 166) with bipolar II disorder, cyclothymia, or bipolar disorder not otherwise specified completed diagnostic interview assessments of PD symptoms and self-report measures of mood symptoms at baseline. They were followed prospectively with diagnostic interviews every 4 months for an average of 3.02 years. Cox proportional hazard regression analyses indicated that overall PD symptom severity significantly predicted shorter time to onset of hypomanic (hazard ratio [HR] = 1.42; p conversion to bipolar I disorder (HR = 2.51; p conversion to bipolar I disorder (HR = 2.77; p < .001), whereas cluster C severity (HR = 1.56; p < .001) predicted shorter time to onset of major depressive episodes. These results support predisposition models in suggesting that PD symptoms may act as a risk factor for a more severe course of BSDs. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  15. Bipolar Disorder and Alcoholism: Are They Related?

    Science.gov (United States)

    ... Are they related? Is there a connection between bipolar disorder and alcoholism? Answers from Daniel K. Hall-Flavin, M.D. Bipolar disorder and alcoholism often occur together. Although the association ...

  16. Design procedure for millimeter-wave InP DHBT stacked power amplifiers

    DEFF Research Database (Denmark)

    Squartecchia, Michele; Johansen, Tom Keinicke; Midili, Virginio

    2015-01-01

    The stacked-transistor concept for power amplifiers (PA) has been investigated in this work. Specifically, this architecture has been applied in the design of millimeter-wave monolithic microwave integrated circuits (MMICs) using indium phosphide (InP) double heterojunction bipolar transistors...

  17. Psychopharmacological treatment of psychotic mania and psychotic bipolar depression compared to non-psychotic mania and non-psychotic bipolar depression.

    Science.gov (United States)

    Bjørklund, Louise B; Horsdal, Henriette T; Mors, Ole; Gasse, Christiane; Østergaard, Søren D

    2017-09-01

    An evidence base for the treatment of mania and bipolar depression with psychotic symptoms is lacking. Nevertheless, clinicians may have a preference for treating episodes of bipolar disorder with or without psychotic symptoms in different ways, which is likely to reflect notions of differential efficacy of treatments between these subtypes. This study aimed to investigate whether the psychopharmacological treatment of psychotic and non-psychotic episodes of mania and bipolar depression, respectively, differs in clinical practice. We conducted a register-based study assessing the psychopharmacological treatment of all individuals receiving their first diagnosis of mania or bipolar depression between 2010 and 2012. The psychopharmacological treatment within 3 months following the time of diagnosis was considered. Potential differences in psychopharmacological treatment between the psychotic and non-psychotic subtypes of mania and bipolar depression, respectively, were investigated by means of Pearson's χ 2 test and logistic regression adjusted for sex and age at diagnosis of bipolar disorder. A total of 827 patients were included in the analyses. The adjusted odds ratio (aOR) for treatment with an antipsychotic was 1.71 (95% confidence interval [CI]: 1.18-2.48, Pbipolar depression. The aOR for treatment with the combination of an antipsychotic and an anticonvulsant was 1.60 (95% CI: 1.06-2.43, Pbipolar psychotic depression. It would be of interest to conduct studies evaluating whether antipsychotics represent the superior pharmacological treatment for psychotic mania and psychotic bipolar depression. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Flexible Proton-Gated Oxide Synaptic Transistors on Si Membrane.

    Science.gov (United States)

    Zhu, Li Qiang; Wan, Chang Jin; Gao, Ping Qi; Liu, Yang Hui; Xiao, Hui; Ye, Ji Chun; Wan, Qing

    2016-08-24

    Ion-conducting materials have received considerable attention for their applications in fuel cells, electrochemical devices, and sensors. Here, flexible indium zinc oxide (InZnO) synaptic transistors with multiple presynaptic inputs gated by proton-conducting phosphorosilicate glass-based electrolyte films are fabricated on ultrathin Si membranes. Transient characteristics of the proton gated InZnO synaptic transistors are investigated, indicating stable proton-gating behaviors. Short-term synaptic plasticities are mimicked on the proposed proton-gated synaptic transistors. Furthermore, synaptic integration regulations are mimicked on the proposed synaptic transistor networks. Spiking logic modulations are realized based on the transition between superlinear and sublinear synaptic integration. The multigates coupled flexible proton-gated oxide synaptic transistors may be interesting for neuroinspired platforms with sophisticated spatiotemporal information processing.

  19. Clinical, Demographic, and Familial Correlates of Bipolar Spectrum Disorders among Offspring of Parents with Bipolar Disorder

    Science.gov (United States)

    Goldstein, Benjamin I.; Shamseddeen, Wael; Axelson, David A.; Kalas, Cathy; Monk, Kelly; Brent, David A.; Kupfer, David J.; Birmaher, Boris

    2010-01-01

    Objective: Despite increased risk, most offspring of parents with bipolar disorder (BP) do not manifest BP. The identification of risk factors for BP among offspring could improve preventive and treatment strategies. We examined this topic in the Pittsburgh Bipolar Offspring Study (BIOS). Method: Subjects included 388 offspring, ages 7-17 years,…

  20. Precursors in adolescence of adult-onset bipolar disorder.

    Science.gov (United States)

    Hiyoshi, Ayako; Sabet, Julia A; Sjöqvist, Hugo; Melinder, Carren; Brummer, Robert J; Montgomery, Scott

    2017-08-15

    Although the estimated contribution of genetic factors is high in bipolar disorder, environmental factors may also play a role. This Swedish register-based cohort study of men examined if physical and psychological characteristics in late adolescence, including factors previously linked with bipolar disorder (body mass index, asthma and allergy), are associated with subsequent bipolar disorder in adulthood. Unipolar depression and anxiety are analysed as additional outcomes to identify bipolar disorder-specific associations. A total of 213,693 men born between 1952 and 1956, who participated in compulsory military conscription assessments in late adolescence were followed up to 2009, excluding men with any psychiatric diagnoses at baseline. Cox regression estimated risk of bipolar disorder, depression and anxiety in adulthood associated with body mass index, asthma, allergy, muscular strength stress resilience and cognitive function in adolescence. BMI, asthma and allergy were not associated with bipolar disorder. Higher grip strength, cognitive function and stress resilience were associated with a reduced risk of bipolar disorder and the other disease outcomes. The sample consisted only of men; even though the characteristics in adolescence pre-dated disease onset, they may have been the consequence of prodromal disease. Associations with body mass index and asthma found by previous studies may be consequences of bipolar disorder or its treatment rather than risk factors. Inverse associations with all the outcome diagnoses for stress resilience, muscular strength and cognitive function may reflect general risks for these psychiatric disorders or intermediary factors. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. GaN transistors for efficient power conversion

    CERN Document Server

    Lidow, Alex; de Rooij, Michael; Reusch, David

    2014-01-01

    The first edition of GaN Transistors for Efficient Power Conversion was self-published by EPC in 2012, and is currently the only other book to discuss GaN transistor technology and specific applications for the technology. More than 1,200 copies of the first edition have been sold through Amazon or distributed to selected university professors, students and potential customers, and a simplified Chinese translation is also available. The second edition has expanded emphasis on applications for GaN transistors and design considerations. This textbook provides technical and application-focused i

  2. Functional remediation for bipolar disorder

    OpenAIRE

    Martínez-Arán, Anabel, 1971-; Torrent, C.; Solé, B.; Bonnín, C.M.; Rosa, A.R.; Sánchez-Moreno, J.; Vieta i Pascual, Eduard, 1963-

    2014-01-01

    Neurocognitive impairment constitutes a core feature of bipolar illness. The main domains affected are verbal memory, attention, and executive functions. Deficits in these areas as well as difficulties to get functional remission seem to be increased associated with illness progression. Several studies have found a strong relationship between neurocognitive impairment and low functioning in bipolar disorder, as previously reported in other illnesses such as schizophrenia. Cognitive remediatio...

  3. Rumination in bipolar disorder: evidence for an unquiet mind

    OpenAIRE

    Ghaznavi, Sharmin; Deckersbach, Thilo

    2012-01-01

    Abstract Depression in bipolar disorder has long been thought to be a state characterized by mental inactivity. However, recent research demonstrates that patients with bipolar disorder engage in rumination, a form of self-focused repetitive cognitive activity, in depressed as well as in manic states. While rumination has long been associated with depressed states in major depressive disorder, the finding that patients with bipolar disorder ruminate in manic states is unique to bipolar disord...

  4. The Dutch Bipolar Offspring Study: 12-Year Follow-Up

    OpenAIRE

    Mesman, Esther; Nolen, Willem A.; Reichart, Catrien G.; Wals, Marjolein; Hillegers, Manon N. J.

    2013-01-01

    Objective: Offspring of bipolar parents have a genetically increased risk of developing mood disorders. In a longitudinal study, the authors followed a bipolar offspring cohort from adolescence into adulthood to determine the onset, prevalence, and early course of mood disorders and other psychopathology. Method: The Dutch bipolar offspring cohort is a fixed cohort initiated in 1997 (N=140; age range at baseline, 12-21 years). Bipolar offspring were psychiatrically evaluated at baseline and a...

  5. Family History in Patients with Bipolar Disorder.

    Science.gov (United States)

    Özdemir, Osman; Coşkun, Salih; Aktan Mutlu, Elif; Özdemir, Pınar Güzel; Atli, Abdullah; Yilmaz, Ekrem; Keskin, Sıddık

    2016-09-01

    In this study, we aimed to better understand the genetic transmission of bipolar disorder by examining the family history of patients. Sixty-three patients with bipolar disorder and their families were included. The final sample comprised 156 bipolar patients and their family members. An inclusion criterion was the presence of bipolar disorder history in the family. The diagnosis of other family members was confirmed by analyzing their files, hospital records, and by calling them to the hospital. Sixty-five patients were women (41.6%) and 91 were men (58.3%) (ratio of men/women: 1.40). When analyzing the results in terms of the transition of disease from the mother's or father's side, similar results were obtained: 25 patients were from the mother's side and 25 patients were from the father's side in 63 cases. The results of our study support the fact that a significant relationship exists between the degree of kinship and the heritability of bipolar disorder and, furthermore, that the effect of the maternal and paternal sides is similar on the transmission of genetic susceptibility.

  6. Design method for a digitally trimmable MOS transistor structure

    DEFF Research Database (Denmark)

    Ning, Feng; Bruun, Erik

    1996-01-01

    A digitally trimmable MOS transistor is a MOS transistor consisting of a drain, a source, and a main gate as well as several subgates. The transconductance of the transistor is tunabledigitally by means of connecting subgates either to the main gate or to the source terminal. In this paper, a sys...

  7. BIPOLAR DISORDER AND METABOLIC SYNDROME: COMORBIDITY OR SIDE EFFECTS OF TREATMENT OF BIPOLAR DISORDER

    OpenAIRE

    Babić, Dragan; Maslov, Boris; Nikolić, Katica; Martinac, Marko; Uzun, Suzana; Kozumplik, Oliver

    2010-01-01

    Objective: There is evidence that people with mental disorders are more likely to suffer from metabolic syndrome. In the last decades there has been an increase in interest for researching metabolic syndrome in psychiatric patients and plenty of evidence about their association. However, investigations on the prevalence of metabolic syndrome in patients with bipolar disorder are still surprisingly rare. The aim of this paper is to analyze comorbidity of bipolar disorder and metabolic syndrome...

  8. A nanoscale piezoelectric transformer for low-voltage transistors.

    Science.gov (United States)

    Agarwal, Sapan; Yablonovitch, Eli

    2014-11-12

    A novel piezoelectric voltage transformer for low-voltage transistors is proposed. Placing a piezoelectric transformer on the gate of a field-effect transistor results in the piezoelectric transformer field-effect transistor that can switch at significantly lower voltages than a conventional transistor. The piezoelectric transformer operates by using one piezoelectric to squeeze another piezoelectric to generate a higher output voltage than the input voltage. Multiple piezoelectrics can be used to squeeze a single piezoelectric layer to generate an even higher voltage amplification. Coupled electrical and mechanical modeling in COMSOL predicts a 12.5× voltage amplification for a six-layer piezoelectric transformer. This would lead to more than a 150× reduction in the power needed for communications.

  9. Mathematical models of bipolar disorder

    Science.gov (United States)

    Daugherty, Darryl; Roque-Urrea, Tairi; Urrea-Roque, John; Troyer, Jessica; Wirkus, Stephen; Porter, Mason A.

    2009-07-01

    We use limit cycle oscillators to model bipolar II disorder, which is characterized by alternating hypomanic and depressive episodes and afflicts about 1% of the United States adult population. We consider two non-linear oscillator models of a single bipolar patient. In both frameworks, we begin with an untreated individual and examine the mathematical effects and resulting biological consequences of treatment. We also briefly consider the dynamics of interacting bipolar II individuals using weakly-coupled, weakly-damped harmonic oscillators. We discuss how the proposed models can be used as a framework for refined models that incorporate additional biological data. We conclude with a discussion of possible generalizations of our work, as there are several biologically-motivated extensions that can be readily incorporated into the series of models presented here.

  10. Bipolar postpartum depression: An update and recommendations.

    Science.gov (United States)

    Sharma, Verinder; Doobay, Minakshi; Baczynski, Christine

    2017-09-01

    Over the past few years there has been a surge of interest in the study of bipolar postpartum depression (PPD); however, questions remain about its prevalence, screening, clinical features, and treatment. Three electronic databases, MEDLINE/PubMed (1966-2016), PsycINFO (1806-2016), and the Cochrane Database of Systematic Reviews, were searched using a combination of the keywords bipolar, depression, postpartum, peripartum, prevalence, screening, diagnosis, treatment, drugs, and psychotherapy. The reference lists of articles identified were also searched. All relevant articles published in English were included. Depending on the population studied, 21.4-54% of women with PPD have a diagnosis of bipolar disorder (BD). Characteristic clinical features include younger age at illness onset, first onset of depression after childbirth, onset immediately after delivery, atypical depressive symptoms, psychotic features, mixed features, and history of BD in first-degree family members. Treatment should be guided by symptom acuity, safety concerns, the patient's response to past treatments, drug tolerability, and breastfeeding preference. In the absence of controlled treatment data, preference should be given to drugs normally indicated for bipolar depression including lithium, quetiapine and lamotrigine. Although antidepressants have been studied in combination with mood stabilizers in bipolar depression, these drugs should be avoided due to likelihood of elevated risk of induction of manic symptoms in the postpartum period. In the postpartum period, bipolar PPD is common, can be differentiated from unipolar PPD, and needs to be identified promptly in order to expedite appropriate treatment. Future studies on pharmacotherapy and psychotherapy should focus on the acute and preventative treatment of bipolar PPD. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Anxiety, stress and perfectionism in bipolar disorder.

    Science.gov (United States)

    Corry, Justine; Green, Melissa; Roberts, Gloria; Frankland, Andrew; Wright, Adam; Lau, Phoebe; Loo, Colleen; Breakspear, Michael; Mitchell, Philip B

    2013-12-01

    Previous reports have highlighted perfectionism and related cognitive styles as a psychological risk factor for stress and anxiety symptoms as well as for the development of bipolar disorder symptoms. The anxiety disorders are highly comorbid with bipolar disorder but the mechanisms that underpin this comorbidity are yet to be determined. Measures of depressive, (hypo)manic, anxiety and stress symptoms and perfectionistic cognitive style were completed by a sample of 142 patients with bipolar disorder. Mediation models were used to explore the hypotheses that anxiety and stress symptoms would mediate relationships between perfectionistic cognitive styles, and bipolar disorder symptoms. Stress and anxiety both significantly mediated the relationship between both self-critical perfectionism and goal attainment values and bipolar depressive symptoms. Goal attainment values were not significantly related to hypomanic symptoms. Stress and anxiety symptoms did not significantly mediate the relationship between self-critical perfectionism and (hypo)manic symptoms. 1. These data are cross-sectional; hence the causality implied in the mediation models can only be inferred. 2. The clinic patients were less likely to present with (hypo)manic symptoms and therefore the reduced variability in the data may have contributed to the null findings for the mediation models with (hypo) manic symptoms. 3. Those patients who were experiencing current (hypo)manic symptoms may have answered the cognitive styles questionnaires differently than when euthymic. These findings highlight a plausible mechanism to understand the relationship between bipolar disorder and the anxiety disorders. Targeting self-critical perfectionism in the psychological treatment of bipolar disorder when there is anxiety comorbidity may result in more parsimonious treatments. © 2013 Published by Elsevier B.V.

  12. Regulation of glycogen synthase kinase-3 during bipolar mania treatment.

    Science.gov (United States)

    Li, Xiaohong; Liu, Min; Cai, Zhuoji; Wang, Gang; Li, Xiaohua

    2010-11-01

    Bipolar disorder is a debilitating psychiatric illness presenting with recurrent mania and depression. The pathophysiology of bipolar disorder is poorly understood, and molecular targets in the treatment of bipolar disorder remain to be identified. Preclinical studies have suggested that glycogen synthase kinase-3 (GSK3) is a potential therapeutic target in bipolar disorder, but evidence of abnormal GSK3 in human bipolar disorder and its response to treatment is still lacking. This study was conducted in acutely ill type I bipolar disorder subjects who were hospitalized for a manic episode. The protein level and the inhibitory serine phosphorylation of GSK3 in peripheral blood mononuclear cells of bipolar manic and healthy control subjects were compared, and the response of GSK3 to antimanic treatment was evaluated. The levels of GSK3α and GSK3β in this group of bipolar manic subjects were higher than healthy controls. Symptom improvement during an eight-week antimanic treatment with lithium, valproate, and atypical antipsychotics was accompanied by a significant increase in the inhibitory serine phosphorylation of GSK3, but not the total level of GSK3, whereas concomitant electroconvulsive therapy treatment during a manic episode appeared to dampen the response of GSK3 to pharmacological treatment. Results of this study suggest that GSK3 can be modified during the treatment of bipolar mania. This finding in human bipolar disorder is in agreement with preclinical data suggesting that inhibition of GSK3 by increasing serine phosphorylation is a response of GSK3 to psychotropics used in bipolar disorder, supporting the notion that GSK3 is a promising molecular target in the pharmacological treatment of bipolar disorder. © 2010 John Wiley and Sons A/S.

  13. Hypnotic susceptibility and affective states in bipolar I and II disorders.

    Science.gov (United States)

    Zhang, Bingren; Wang, Jiawei; Zhu, Qisha; Ma, Guorong; Shen, Chanchan; Fan, Hongying; Wang, Wei

    2017-11-09

    Highly hypnotizable individuals have impaired executive function, elevated motor impulsivity and increased emotional sensitivity, which are sometimes found in bipolar disorder patients. It is then reasonable to assume that certain aspects of hypnotic susceptibility differ with the types of bipolar disorder. The Stanford Hypnotic Susceptibility Scale: Form C (SHSS:C) test, the Mood Disorder Questionnaire (MDQ), the Hypomanic Checklist-32 (HCL-32) and the Plutchick-van Praag Depression Inventory (PVP) were applied to 62 patients with bipolar I disorder, 33 bipolar II disorder, and 120 healthy volunteers. The passing rate of the SHSS:C 'Moving hands apart' item was higher in bipolar I patients than in controls, whereas for 'Mosquito hallucination' the rate was lower. Bipolar I and II patients scored significantly higher on MDQ, HCL-32 and PVP scales than controls. The passing rates of 'Mosquito hallucination' in controls, 'Arm rigidity' in bipolar I, and 'Age regression' in bipolar II predicted the respective MDQ scores. In contrast to cognitive suggestions, bipolar I patients followed motor suggestions more often under hypnosis. Furthermore, both bipolar disorder patients and healthy volunteers demonstrated associations between mania levels and certain hypnotic susceptibility features. Our study aids in better understanding the altered conscious states in bipolar disorders, and encourages the use of related psychotherapy for these patients.

  14. [Pediatric bipolar disorder - case report of a bipolar patient with disease onset in childhood and adolescence: implications for diagnosis and therapy].

    Science.gov (United States)

    Lackner, N; Birner, A; Bengesser, S A; Reininghaus, B; Kapfhammer, H P; Reininghaus, E

    2014-11-01

    In recent years, intense controversies have evolved about the existence and exact diagnostic criteria of pediatric bipolar affective disorder. The present study aims to discuss pediatric bipolar affective disorder based on the current literature focussing on the diagnostic prospects. Based on a case study, a process of bipolar disorder developed in childhood is depicted exemplarily. Because of the high comorbidity and overlapping symptoms of paediatric bipolar affective disorder and other psychiatric disorders, the major impact of the differential diagnosis has to be stressed. An early diagnosis and the treatment possibilities are discussed. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Transtorno bipolar do humor e gênero Bipolar affective disorder and gender

    Directory of Open Access Journals (Sweden)

    Rodrigo da Silva Dias

    2006-01-01

    Full Text Available Embora o transtorno bipolar (TB ocorra quase igualmente em ambos os sexos, a fenomenologia e o curso da doença diferem no homem e na mulher. No entanto, há evidências de que mulheres bipolares, mais que os homens, apresentariam início mais tardio (em especial na quinta década de vida, ciclagem rápida, mais episódios depressivos, mais mania disfórica que eufórica, estados mistos e evolução do tipo bipolar II, ainda que os achados nem sempre sejam consistentes. Embora o risco de comorbidades no TB inclua, para ambos os gêneros, abuso de álcool e drogas, homens bipolares teriam maior probabilidade de ser alcoolistas, não procurar tratamento e de se suicidar. Hipóteses sugeridas para explicar tais diferenças variam daquelas centradas em aspectos culturais ou psicológicos para as que focalizam os sistemas hormonais, como os esteróides gonadais ou o eixo tireoidiano, e até mesmo a anatomia cerebral. A influência do ciclo reprodutivo (ciclo menstrual, gravidez e menopausa sobre as opções terapêuticas no tratamento do TB é apresentada na última parte desta revisão.Although the bipolar disorder (BD occurs almost with the same frequency in both genders, the phenomenology and the outcome of the illness differ between them. Nevertheless, there is evidence that women with BD show, more than men, delayed beginning, especially in their fifth decade, more rapid cycling outcome, more depressive episodes, more dysphoric mania, more mixed states and more BD type II. Even so, the findings are not always consistent. Although the risk of comorbidities in BD includes, for both the sorts, excessive alcoholic consumption and drugs, bipolar men would have greater probability of being alcohol dependent, of not seeking treatment and of committing suicide. Suggested hypotheses to explain such differences vary from those centered in cultural or psychological aspects to those that focus on the steroids hormones, and other hormones such as cortisol

  16. Problems of noise modeling in the presence of total current branching in high electron mobility transistor and field-effect transistor channels

    International Nuclear Information System (INIS)

    Shiktorov, P; Starikov, E; Gružinskis, V; Varani, L; Sabatini, G; Marinchio, H; Reggiani, L

    2009-01-01

    In the framework of analytical and hydrodynamic models for the description of carrier transport and noise in high electron mobility transistor/field-effect transistor channels the main features of the intrinsic noise of transistors are investigated under continuous branching of the current between channel and gate. It is shown that the current-noise and voltage-noise spectra at the transistor terminals contain an excess noise related to thermal excitation of plasma wave modes in the dielectric layer between the channel and gate. It is found that the set of modes of excited plasma waves can be governed by the external embedding circuits, thus violating a universal description of noise in terms of Norton and Thevenin noise generators

  17. Ionizing radiations simulation on bipolar components

    International Nuclear Information System (INIS)

    Montagner, X.

    1999-01-01

    This thesis presents the ionizing radiation effects on bipolar components and more specially their behavior facing the total dose. The first part is devoted to the radiation environments with a special attention to the spatial environments and new emergent environments. The specificities of bipolar components are then presented and their behavior facing the interactions. The physical mechanisms bound to the dose rate are also discussed. The second part presents a physical analysis of degradations induced by the cumulated dosimetry on bipolar components and simulation with the ATLAS code. The third part exposes an electric empirical simulation induced by the cumulated dose in static conditions. (A.L.B.)

  18. Transistor challenges - A DRAM perspective

    International Nuclear Information System (INIS)

    Faul, Juergen W.; Henke, Dietmar

    2005-01-01

    Key challenges of the transistor scaling from a DRAM perspective will be reviewed. Both, array transistors as well as DRAM support devices face challenges that differ essentially from high performance logic device scaling. As a major difference, retention time and standby current requirements characterize special boundary conditions in the DRAM device design. Array device scaling is determined by a chip size driven aggressive node scaling. To continue scaling, major innovations need to be introduced into state-of-the-art planar array transistors. Alternatively, non planar device concepts will have to be evaluated. Support device design for DRAMs is driven by today's market demand for increased chip performances at little to no extra cost. Major innovations are required to continue that path. Besides this strive for performance increase, special limitations for 'on pitch' circuits at the array edge will come up due to the aggressive cell size scaling

  19. Neuropsychological Impairments in Schizophrenia and Psychotic Bipolar Disorder: Findings from the Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) Study

    Science.gov (United States)

    Hill, S. Kristian; Reilly, James L.; Keefe, Richard S.E.; Gold, James M.; Bishop, Jeffrey R.; Gershon, Elliot S.; Tamminga, Carol A.; Pearlson, Godfrey D.; Keshavan, Matcheri S.; Sweeney, John A.

    2017-01-01

    Objective Familial neuropsychological deficits are well established in schizophrenia but remain less well characterized in other psychotic disorders. This study from the Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) consortium 1) compares cognitive impairment in schizophrenia and bipolar disorder with psychosis, 2) tests a continuum model of cognitive dysfunction in psychotic disorders, 3) reports familiality of cognitive impairments across psychotic disorders, and 4) evaluates cognitive impairment among nonpsychotic relatives with and without cluster A personality traits. Method Participants included probands with schizophrenia (N=293), psychotic bipolar disorder (N=227), schizoaffective disorder (manic, N=110; depressed, N=55), their first-degree relatives (N=316, N=259, N=133, and N=64, respectively), and healthy comparison subjects (N=295). All participants completed the Brief Assessment of Cognition in Schizophrenia (BACS) neuropsychological battery. Results Cognitive impairments among psychotic probands, compared to healthy comparison subjects, were progressively greater from bipolar disorder (z=−0.77) to schizoaffective disorder (manic z=−1.08; depressed z=−1.25) to schizophrenia (z=−1.42). Profiles across subtests of the BACS were similar across disorders. Familiality of deficits was significant and comparable in schizophrenia and bipolar disorder. Of particular interest were similar levels of neuropsychological deficits in relatives with elevated cluster A personality traits across proband diagnoses. Nonpsychotic relatives of schizophrenia probands without these personality traits exhibited significant cognitive impairments, while relatives of bipolar probands did not. Conclusions Robust cognitive deficits are present and familial in schizophrenia and psychotic bipolar disorder. Severity of cognitive impairments across psychotic disorders was consistent with a continuum model, in which more prominent affective features and less

  20. Liquid crystals for organic transistors (Conference Presentation)

    Science.gov (United States)

    Hanna, Jun-ichi; Iino, Hiroaki

    2016-09-01

    Liquid crystals are a new type of organic semiconductors exhibiting molecular orientation in self-organizing manner, and have high potential for device applications. In fact, various device applications have been proposed so far, including photosensors, solar cells, light emitting diodes, field effect transistors, and so on.. However, device performance in those fabricated with liquid crystals is less than those of devices fabricated with conventional materials in spite of unique features of liquid crystals. Here we discuss how we can utilize the liquid crystallinity in organic transistors and how we can overcome conventional non-liquid crystalline organic transistor materials. Then, we demonstrate high performance organic transistors fabricated with a smectic E liquid crystal of Ph-BTBT-10, which show high mobility of over 10cm2/Vs and high thermal durability of over 200oC in OFETs fabricated with its spin-coated polycrystalline thin films.

  1. The electrolysis time on electrosynthesis of hydroxyapatite with bipolar membrane

    Science.gov (United States)

    Nur, Adrian; Jumari, Arif; Budiman, Anatta Wahyu; Puspitaningtyas, Stella Febianti; Cahyaningrum, Suci; Nazriati, Nazriati; Fajaroh, Fauziatul

    2018-02-01

    The electrochemical method with bipolar membrane has been successfully used for the synthesis of hydroxyapatite. In this work, we have developed 2 chambers electrolysis system separated by a bipolar membrane. The membrane was used to separate cations (H+ ions produced by the oxidation of water at the anode) and anions (OH- ions produced by the reduction of water at the cathode). With this system, we have designed that OH- ions still stay in the anions chamber because OH- ions was very substantial in the hydroxyapatite particles formation. The aim of this paper was to compare the electrolysis time on electrosynthesis of hydroxyapatite with and without the bipolar membrane. The electrosynthesis was performed at 500 mA/cm2 for 0.5 to 2 hours at room temperature and under ultrasonic cleaner to void agglomeration with and without the bipolar membrane. The electrosynthesis of hydroxyapatite with the bipolar membrane more effective than without the bipolar membrane. The hydroxyapatite has been appeared at 0.5 h of the electrolysis time with the bipolar membrane (at the cathode chamber) while it hasn't been seen without the bipolar membrane. The bipolar membrane prevents OH- ions migrate to the cation chamber. The formation of HA becomes more effective because OH- ions just formed HA particle.

  2. Identifying early indicators in bipolar disorder: a qualitative study.

    Science.gov (United States)

    Benti, Liliane; Manicavasagar, Vijaya; Proudfoot, Judy; Parker, Gordon

    2014-06-01

    The identification of early markers has become a focus for early intervention in bipolar disorder. Using a retrospective, qualitative methodology, the present study compares the early experiences of participants with bipolar disorder to those with unipolar depression up until their first diagnosed episode. The study focuses on differences in early home and school environments as well as putative differences in personality characteristics between the two groups. Finally we a compare and contrast prodromal symptoms in these two populations. Thirty-nine participants, 20 diagnosed with unipolar depression and 19 diagnosed with bipolar disorder, took part in the study. A semi-structured interview was developed to elicit information about participants' experiences prior to their first episode. Participants with bipolar disorder reported disruptive home environments, driven personality features, greater emotion dysregulation and adverse experiences during the school years, whereas participants with depression tended to describe more supportive home environments, and more compliant and introvert personality traits. Retrospective data collection and no corroborative evidence from other family members. No distinction was made between bipolar I and bipolar II disorder nor between melancholic and non-melancholic depression in the sample. Finally the study spanned over a 12-month period which does not allow for the possibility of diagnostic reassignment of some of the bipolar participants to the unipolar condition. These findings indicate that there may be benefits in combining both proximal and distal indicators in identifying a bipolar disorder phenotype which, in turn, may be relevant to the development of early intervention programs for young people with bipolar disorder.

  3. Silicon doping techniques using chemical vapor dopant deposition

    NARCIS (Netherlands)

    Popadic, M.

    2009-01-01

    Ultrashallow junctions are essential for the achievement of superior transistor performance, both in MOSFET and bipolar transistors. The stringent demands require state-of-the-art fabrication techniques. At the same time, in a different context, the accurate fabrication of various n type doping

  4. Treatment outcomes of acute bipolar depressive episode with psychosis.

    Science.gov (United States)

    Caldieraro, Marco Antonio; Dufour, Steven; Sylvia, Louisa G; Gao, Keming; Ketter, Terence A; Bobo, William V; Walsh, Samantha; Janos, Jessica; Tohen, Mauricio; Reilly-Harrington, Noreen A; McElroy, Susan L; Shelton, Richard C; Bowden, Charles L; Deckersbach, Thilo; Nierenberg, Andrew A

    2018-05-01

    The impact of psychosis on the treatment of bipolar depression is remarkably understudied. The primary aim of this study was to compare treatment outcomes of bipolar depressed individuals with and without psychosis. The secondary aim was to compare the effect of lithium and quetiapine, each with adjunctive personalized treatments (APTs), in the psychotic subgroup. We assessed participants with DSM-IV bipolar depression included in a comparative effectiveness study of lithium and quetiapine with APTs (the Bipolar CHOICE study). Severity was assessed by the Bipolar Inventory of Symptoms Scale (BISS) and by the Clinical Global Impression Scale-Severity-Bipolar Version (CGI-S-BP). Mixed models were used to assess the course of symptom change, and Cox regression survival analysis was used to assess the time to remission. Psychotic features were present in 10.6% (n = 32) of the depressed participants (n = 303). Those with psychotic features had higher scores on the BISS before (75.2 ± 17.6 vs. 54.9 ± 16.3; P Bipolar depressive episodes with psychotic features are more severe, and compared to nonpsychotic depressions, present a similar course of improvement. Given the small number of participants presenting psychosis, the lack of statistically significant difference between lithium- and quetiapine-based treatment of psychotic bipolar depressive episodes needs replication in a larger sample. © 2018 Wiley Periodicals, Inc.

  5. [Drug Abuse Comorbidity in Bipolar Disorder].

    Science.gov (United States)

    Ortiz, Óscar Medina

    2012-06-01

    Drug use among patients with bipolar disorder is greater than the one observed in the general population; psychotic episodes are likely to occur after consumption. This has implications in the prevention, etiology, management, and treatment of the disease. Bipolar disorder pathology is likely to have positive response to pharmacological treatment. Therefore, identifying the strategies with better results to be applied in these patients is fundamental for psychiatrists and primary care physicians. Review literature in order to determine the prevalence and characteristics of drug abuse in patients with bipolar disorder and establish the pharmacological strategies that have produced better results. Literature review. A great variety of studies demonstrate the relationship between bipolar disorder and drug use disorder. These patients are hospitalized more frequently, have an earlier onset of the disease, and present a larger number of depressive episodes and suicide attempts which affect the course of the disease. The drug with better results in the treatment of these patients is Divalproate. Satisfactory results have been also obtained with other mood stabilizers such as carbamazepine, lamotrigine, and the antipsychotic aripiprazole. Substance abuse is present in a large number of patients with bipolar disorder. The Divalproate is the drug that has shown better results in the studies. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  6. Catastrophic Failure and Fault-Tolerant Design of IGBT Power Electronic Converters - An Overview

    DEFF Research Database (Denmark)

    Wu, Rui; Blaabjerg, Frede; Wang, Huai

    2013-01-01

    Reliability is one of the key issues for the application of Insulated Gate Bipolar Transistors (IGBTs) in power electronic converters. Many efforts have been devoted to the reduction of IGBT wear out failure induced by accumulated degradation and catastrophic failure triggered by single-event ove......Reliability is one of the key issues for the application of Insulated Gate Bipolar Transistors (IGBTs) in power electronic converters. Many efforts have been devoted to the reduction of IGBT wear out failure induced by accumulated degradation and catastrophic failure triggered by single...

  7. Taiwan consensus of pharmacological treatment for bipolar disorder

    Directory of Open Access Journals (Sweden)

    Ya-Mei Bai

    2013-10-01

    Full Text Available Bipolar disorder is an important psychiatric disorder with different disease phases. The pharmacological treatment is complicated, and is updated frequently as new research evidence emerges. For the purpose of international collaboration, research, and education, the Taiwan consensus of pharmacological treatment for bipolar disorders was initiated by the Taiwanese Society of Biological Psychiatry and Neuropsychopharmacology (TSBPN – the Bipolar Chapter, which was established in August 2010 and approved as a member of International Society of Bipolar Disorder. TSBPN is the country member of the World Federation of Societies of Biological Psychiatry (WFSBP. The development of the Taiwan consensus for bipolar disorder was mainly based on the template of WFSBP Guidelines, with references to other international guidelines including the Canadian Network for Mood and Anxiety Treatments, and British Association for Psychopharmacology. We have also added Taiwanese experts’ experience, Taiwan national health insurance data, and the indications for the pharmacological treatment of bipolar disorder given by the Taiwan Department of Health, to emphasize the balance between efficacy and safety, and to make this consensus a concise, empirical, and important reference for clinical psychiatric practice.

  8. Antidepressant Treatment for Acute Bipolar Depression: An Update

    Directory of Open Access Journals (Sweden)

    Ben H. Amit

    2012-01-01

    Full Text Available While studies in the past have focused more on treatment of the manic phase of bipolar disorder (BD, recent findings demonstrate the depressive phase to be at least as debilitating. However, in contrast to unipolar depression, depression in bipolar patients exhibits a varying response to antidepressants, raising questions regarding their efficacy and tolerability. Methods. We conducted a MEDLINE and Cochrane Collaboration Library search for papers published between 2005 and 2011 on the subject of antidepressant treatment of bipolar depression. Sixty-eight articles were included in the present review. Results. While a few studies did advocate the use of antidepressants, most well-controlled studies failed to show a robust effect of antidepressants in bipolar depression, regardless of antidepressant class or bipolar subtype. There was no significant increase in the rate of manic/hypomanic switch, especially with concurrent use of mood stabilizers. Prescribing guidelines published in recent years rely more on atypical antipsychotics, especially quetiapine, as a first-line therapy. Conclusions. Antidepressants probably have no substantial role in acute bipolar depression. However, in light of conflicting results between studies, more well-designed trials are warranted.

  9. An investigation of coated aluminium bipolar plates for PEMFC

    International Nuclear Information System (INIS)

    Lin, Chien-Hung; Tsai, Sung-Ying

    2012-01-01

    Highlights: ► Coated aluminium bipolar plates demonstrate the hydrophobic property than the raw material. ► The corrosion behaviour of bipolar plate decreases the PEMFC performance severely. ► These PEMFCs are measured by current–voltage (I–V) curve test. ► The oxide film increases the interfacial contact resistance. -- Abstract: The performance of Al-alloy bipolar plates for the PEMFC (proton exchange membrane fuel cell) system is investigated in this paper. The metallic bipolar plates are modified with a Ni–P coating. The performance of the Al-alloy bipolar plates is evaluated by the coating structure, corrosion resistance, contact angle and single cell performance. The results indicate that the coated aluminium bipolar plates demonstrate hydrophobic and anti-corrosive properties. The hydrophobic property increases the contact angle on the surface from 46.08° to 80.51°. Meanwhile, the corrosion rate of the Ni–P coating can be over 1 order of magnitude lower than that of the substrate. Hence, the substrate with the coating maintains superior performance under the long term test. The present study proves that both the hydrophobicity and corrosion resistance significantly affect the metallic bipolar plate.

  10. Methodological recommendations for cognition trials in bipolar disorder by the International Society for Bipolar Disorders Targeting Cognition Task Force

    DEFF Research Database (Denmark)

    Miskowiak, K W; Burdick, K E; Martinez-Aran, A

    2017-01-01

    OBJECTIVES: To aid the development of treatment for cognitive impairment in bipolar disorder, the International Society for Bipolar Disorders (ISBD) convened a task force to create a consensus-based guidance paper for the methodology and design of cognition trials in bipolar disorder. METHODS...... symptoms and concomitant medication. Task force recommendations are to: (i) enrich trials with objectively measured cognitively impaired patients; (ii) generally select a broad cognitive composite score as the primary outcome and a functional measure as a key secondary outcome; and (iii) include remitted...... of treatments to illness stage and using a multimodal approach. CONCLUSIONS: This ISBD task force guidance paper provides the first consensus-based recommendations for cognition trials in bipolar disorder. Adherence to these recommendations will likely improve the sensitivity in detecting treatment efficacy...

  11. Large magnetocurrents in double-barrier tunneling transistors

    International Nuclear Information System (INIS)

    Lee, J.H.; Jun, K.-I.; Shin, K.-H.; Park, S.Y.; Hong, J.K.; Rhie, K.; Lee, B.C.

    2005-01-01

    Magnetic tunneling transistors (MTT) with double tunneling barriers are fabricated. The structure of the transistor is AFM/FM/I/FM/I/FM/AFM, and ferromagnetic layers serve as the emitter, base and collector. This double-barrier tunneling transistor (DBTT) has an advantage of controlling the potential between the base and collector, compared to the Schottky-barrier-based base and collector of MTT. We found that the collector current density of DBTT is at least 10 3 times larger than that of conventional MTT, since tunneling through AlO x barrier provides much larger current density than that through Schottky barrier

  12. Life events and bipolar disorder : The influence of life events on the onset and course of bipolar disorder

    NARCIS (Netherlands)

    Kemner, Sanne

    2017-01-01

    In the Netherlands, bipolar disorder (also known as manic-depressive illness) is diagnosed in approximately 2% of the population. The disorder is characterized by alternating periods of raised activity and (manic) mood and periods of reduced activity with lowered (depressed) mood. Bipolar disorder

  13. Ambipolar organic tri-gate transistor for low-power complementary electronics

    NARCIS (Netherlands)

    Torricelli, F.; Ghittorelli, M.; Smits, E.C.P.; Roelofs, C.; Janssen, R.A.J.; Gelinck, G.H.; Kovács-Vajna, Z.M.; Cantatore, E.

    2016-01-01

    Ambipolar transistors typically suffer from large off-current inherently due to ambipolar conduction. Using a tri-gate transistor it is shown that it is possible to electrostatically switch ambipolar polymer transistors from ambipolar to unipolar mode. In unipolar mode, symmetric characteristics

  14. Stretchable transistors with buckled carbon nanotube films as conducting channels

    Science.gov (United States)

    Arnold, Michael S; Xu, Feng

    2015-03-24

    Thin-film transistors comprising buckled films comprising carbon nanotubes as the conductive channel are provided. Also provided are methods of fabricating the transistors. The transistors, which are highly stretchable and bendable, exhibit stable performance even when operated under high tensile strains.

  15. Metal nanoparticle film-based room temperature Coulomb transistor.

    Science.gov (United States)

    Willing, Svenja; Lehmann, Hauke; Volkmann, Mirjam; Klinke, Christian

    2017-07-01

    Single-electron transistors would represent an approach to developing less power-consuming microelectronic devices if room temperature operation and industry-compatible fabrication were possible. We present a concept based on stripes of small, self-assembled, colloidal, metal nanoparticles on a back-gate device architecture, which leads to well-defined and well-controllable transistor characteristics. This Coulomb transistor has three main advantages. By using the scalable Langmuir-Blodgett method, we combine high-quality chemically synthesized metal nanoparticles with standard lithography techniques. The resulting transistors show on/off ratios above 90%, reliable and sinusoidal Coulomb oscillations, and room temperature operation. Furthermore, this concept allows for versatile tuning of the device properties such as Coulomb energy gap and threshold voltage, as well as period, position, and strength of the oscillations.

  16. Low-frequency noise in single electron tunneling transistor

    DEFF Research Database (Denmark)

    Tavkhelidze, A.N.; Mygind, Jesper

    1998-01-01

    The noise in current biased aluminium single electron tunneling (SET) transistors has been investigated in the frequency range of 5 mHz ..., we find the same input charge noise, typically QN = 5 × 10–4 e/Hz1/2 at 10 Hz, with and without the HF shielding. At lower frequencies, the noise is due to charge trapping, and the voltage noise pattern superimposed on the V(Vg) curve (voltage across transistor versus gate voltage) strongly depends...... when ramping the junction voltage. Dynamic trapping may limit the high frequency applications of the SET transistor. Also reported on are the effects of rf irradiation and the dependence of the SET transistor noise on bias voltage. ©1998 American Institute of Physics....

  17. High rate lithium/thionyl chloride bipolar battery development

    Science.gov (United States)

    Russell, P. G.; Goebel, F.

    The lithium/thionyl chloride ( {Li}/{SOCl2}) electrochemistry is capable of providing high power and high specific power, especially under pulse discharge conditions, when cells containing thin components are arranged in a bipolar configuration. This paper describes recent work concerned with bipolar cell design, cathode evaluation, component manufacturing methods, and the assembly and testing of bipolar modules containing up to 150 cells for Sonobuoy application.

  18. High rate lithium/thionyl chloride bipolar battery development

    Energy Technology Data Exchange (ETDEWEB)

    Russell, P.G. [Yardney Technical Products, Inc., Pawcatuck, CT (United States); Goebel, F. [Yardney Technical Products, Inc., Pawcatuck, CT (United States)

    1995-04-01

    The lithium/thionyl chloride (Li/SOCl{sub 2}) electrochemistry is capable of providing high power and high specific power, especially under pulse discharge conditions, when cells containing thin components are arranged in a bipolar configuration. This paper describes recent work concerned with bipolar cell design, cathode evaluation, component manufacturing methods, and the assembly and testing of bipolar modules containing up to 150 cells for Sonobuoy application. (orig.)

  19. Uniformity of fully gravure printed organic field-effect transistors

    International Nuclear Information System (INIS)

    Hambsch, M.; Reuter, K.; Stanel, M.; Schmidt, G.; Kempa, H.; Fuegmann, U.; Hahn, U.; Huebler, A.C.

    2010-01-01

    Fully mass-printed organic field-effect transistors were made completely by means of gravure printing. Therefore a special printing layout was developed in order to avoid register problems in print direction. Upon using this layout, contact pads for source-drain electrodes of the transistors are printed together with the gate electrodes in one and the same printing run. More than 50,000 transistors have been produced and by random tests a yield of approximately 75% has been determined. The principle suitability of the gravure printed transistors for integrated circuits has been shown by the realization of ring oscillators.

  20. Theory and application of dual-transistor charge separation analysis

    International Nuclear Information System (INIS)

    Fleetwood, D.M.; Schwank, J.R.; Winokur, P.S.; Sexton, F.W.; Shaneyfelt, M.R.

    1989-01-01

    The authors describe a dual-transistor charge separation method to evaluate the radiation response of MOS transistors. This method requires that n- and p-channel transistors with identically processed oxides be irradiated under identical conditions at the same oxide electric fields. Combining features of single-transistor midgap and mobility methods, the authors show how one may determine threshold voltage shifts due to oxide-trapped and interface-trapped charge from standard threshold voltage and mobility measurements. These measurements can be made at currents 2-5 orders of magnitude higher than those required for midgap, subthreshold slope, and charge-pumping methods. The dual-transistor method contains no adjustable parameters, and includes an internal self-consistency check. The accuracy of the method is verified by comparison to midgap, subthreshold slope, and charge-pumping methods for several MOS processes and technologies

  1. Organic electrochemical transistors

    KAUST Repository

    Rivnay, Jonathan; Inal, Sahika; Salleo, Alberto; Owens, Ró isí n M.; Berggren, Magnus; Malliaras, George G.

    2018-01-01

    Organic electrochemical transistors (OECTs) make effective use of ion injection from an electrolyte to modulate the bulk conductivity of an organic semiconductor channel. The coupling between ionic and electronic charges within the entire volume

  2. Bipolar Disorder

    Science.gov (United States)

    ... one or other traumatic event Drug or alcohol abuse Complications Left untreated, bipolar disorder can result in serious problems that affect every area of your life, such as: Problems related to drug and alcohol use Suicide or suicide attempts Legal or financial problems Damaged ...

  3. Self-Consistent Study of Conjugated Aromatic Molecular Transistors

    International Nuclear Information System (INIS)

    Jing, Wang; Yun-Ye, Liang; Hao, Chen; Peng, Wang; Note, R.; Mizuseki, H.; Kawazoe, Y.

    2010-01-01

    We study the current through conjugated aromatic molecular transistors modulated by a transverse field. The self-consistent calculation is realized with density function theory through the standard quantum chemistry software Gaussian03 and the non-equilibrium Green's function formalism. The calculated I – V curves controlled by the transverse field present the characteristics of different organic molecular transistors, the transverse field effect of which is improved by the substitutions of nitrogen atoms or fluorine atoms. On the other hand, the asymmetry of molecular configurations to the axis connecting two sulfur atoms is in favor of realizing the transverse field modulation. Suitably designed conjugated aromatic molecular transistors possess different I – V characteristics, some of them are similar to those of metal-oxide-semiconductor field-effect transistors (MOSFET). Some of the calculated molecular devices may work as elements in graphene electronics. Our results present the richness and flexibility of molecular transistors, which describe the colorful prospect of next generation devices. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  4. Internet use by patients with bipolar disorder

    DEFF Research Database (Denmark)

    Bauer, Rita; Conell, Jörn; Glenn, Tasha

    2016-01-01

    There is considerable international interest in online education of patients with bipolar disorder, yet little understanding of how patients use the Internet and other sources to seek information. 1171 patients with a diagnosis of bipolar disorder in 17 countries completed a paper-based, anonymous...... survey. 81% of the patients used the Internet, a percentage similar to the general public. Older age, less education, and challenges in country telecommunications infrastructure and demographics decreased the odds of using the Internet. About 78% of the Internet users looked online for information...... on bipolar disorder or 63% of the total sample. More years of education in relation to the country mean, and feeling very confident about managing life decreased the odds of seeking information on bipolar disorder online, while having attended support groups increased the odds. Patients who looked online...

  5. Quetiapine for the continuation treatment of bipolar depression : naturalistic prospective case series from the Stanley Bipolar Treatment Network

    NARCIS (Netherlands)

    Suppes, Trisha; Kelly, Dorothy I.; Keck, Paul E.; McElroy, Susan L.; Altshuler, Lori L.; Mintz, Jim; Frye, Mark A.; Nolen, Willem A.; Luckenbaugh, David A.; Post, Robert M.; Leverich, Gabriele S.; Kupka, Ralph W.; Grunze, Heinz

    Continuation treatment for bipolar disorder often consists of a mood stabilizer and a second-generation antipsychotic. Quetiapine has been shown to be an effective treatment for acute mania and acute bipolar depression, but there are limited data for its use in continuation treatment. This study

  6. Understanding and control of bipolar self-doping in copper nitride

    International Nuclear Information System (INIS)

    Fioretti, Angela N.; Tamboli, Adele C.; Caskey, Christopher M.; Toberer, Eric S.; Schwartz, Craig P.; Nordlund, Dennis; Vinson, John; Prendergast, David; Tuomisto, Filip; Linez, Florence; Christensen, Steven T.; Lany, Stephan; Zakutayev, Andriy

    2016-01-01

    Semiconductor materials that can be doped both n-type and p-type are desirable for diode-based applications and transistor technology. Copper nitride (Cu_3N) is a metastable semiconductor with a solar-relevant bandgap that has been reported to exhibit bipolar doping behavior. However, deeper understanding and better control of the mechanism behind this behavior in Cu_3N is currently lacking in the literature. In this work, we use combinatorial growth with a temperature gradient to demonstrate both conduction types of phase-pure, sputter-deposited Cu_3N thin films. Room temperature Hall effect and Seebeck effect measurements show n-type Cu_3N with 10"1"7 electrons/cm"3 for low growth temperature (≈35 °C) and p-type with 10"1"5 holes/cm"3–10"1"6 holes/cm"3 for elevated growth temperatures (50 °C–120 °C). Mobility for both types of Cu_3N was ≈0.1 cm"2/Vs–1 cm"2/Vs. Additionally, temperature-dependent Hall effect measurements indicate that ionized defects are an important scattering mechanism in p-type films. By combining X-ray absorption spectroscopy and first-principles defect theory, we determined that V_C_u defects form preferentially in p-type Cu_3N, while Cu_i defects form preferentially in n-type Cu_3N, suggesting that Cu_3N is a compensated semiconductor with conductivity type resulting from a balance between donor and acceptor defects. Based on these theoretical and experimental results, we propose a kinetic defect formation mechanism for bipolar doping in Cu_3N that is also supported by positron annihilation experiments. Overall, the results of this work highlight the importance of kinetic processes in the defect physics of metastable materials and provide a framework that can be applied when considering the properties of such materials in general.

  7. Smartphone-based objective monitoring in bipolar disorder

    DEFF Research Database (Denmark)

    Faurholt-Jepsen, Maria; Bauer, Michael; Kessing, Lars Vedel

    2018-01-01

    , anxiety, substance abuse, eating disorder, schizophrenia and bipolar disorder have been developed and used. The present paper presents the status and findings from studies using automatically generated objective smartphone data in the monitoring of bipolar disorder, and addresses considerations...

  8. Suicide attempts and clinical features of bipolar patients

    OpenAIRE

    Berkol, Tongu? D.; ?slam, Serkan; K?rl?, Ebru; P?narba??, Rasim; ?zy?ld?r?m, ?lker

    2016-01-01

    Objectives: To identify clinical predictors of suicide attempts in patients with bipolar disorder. Methods: This study included bipolar patients who were treated in the Psychiatry Department, Haseki Training and Research Hospital, Istanbul, Turkey, between 2013 and 2014; an informed consent was obtained from the participants. Two hundred and eighteen bipolar patients were assessed by using the structured clinical interview for Diagnostic and Statistical Manual of Mental Disorders, 4th edition...

  9. High rate lithium-thionyl chloride bipolar battery development

    Energy Technology Data Exchange (ETDEWEB)

    Russell, P.G.; Goebel, F. [Yardney Technical Products, Inc., Pawcatuck, CT (United States)

    1994-12-31

    The lithium/thionyl chloride system is capable of providing both high power and high energy density when cells containing thin components are arranged in a bipolar configuration. Electrode current densities in excess of 300mA/cm{sup 2} are achieved during pulse discharge. The present work is concerned with bipolar cell design, cathode evaluation, component manufacturing methods, and the assembly and testing of bipolar modules containing up to 150 cells.

  10. Safety and efficacy of quetiapine in bipolar depression.

    Science.gov (United States)

    Bogart, Gregory T; Chavez, Benjamin

    2009-11-01

    To review the clinical data investigating the efficacy and safety of quetiapine in bipolar depression. Searches of MEDLINE and PubMed (1977-July 2009) were conducted using the key words quetiapine and bipolar depression. The references of literature found were cross-referenced. The pharmaceutical company that produces quetiapine was contacted to obtain the posters for the EMBOLDEN I and EMBOLDEN II trials. Only double-blind, placebo-controlled trials were included for review, as well as any subanalyses of the literature that matched this criterion. There was a total of 5 double-blind, placebo-controlled trials and 5 subanalyses reviewed. The results of these data demonstrated quetiapine's efficacy in the treatment of depressive phases of bipolar disorder, including statistically significant improvement in the Montgomery-Asberg Depression Rating Scale (MADRS). In the trials reviewed in this article, the change in MADRS scores ranged from -15.4 to -16.94 within the quetiapine groups, and from -10.26 to -11.93 in the placebo groups. There were also statistically significant improvements in the Hamilton Anxiety Rating Scale, the Short Form of the Quality of Life Enjoyment and Satisfaction Questionnaire, the Pittsburgh Sleep Quality Index, and the Sheehan Disability Scale. All of these trials had a duration of 8 weeks and therefore cannot be applied to the long-term use of quetiapine in bipolar depression. The most common adverse events were sedation, somnolence, and dry mouth. The overall dropout rates for the trials reviewed ranged from 24% to 47%. Based on the literature reviewed here, quetiapine appears to be a safe and efficacious short-term treatment option for bipolar depression. Patients with bipolar type I showed greater improvement on the MADRS than those with bipolar type II. Patients with a rapid-cycling disease course showed an improvement in depressive symptoms, regardless of bipolar type.

  11. High mobility polymer gated organic field effect transistor using zinc ...

    Indian Academy of Sciences (India)

    Organic thin film transistors were fabricated using evaporated zinc phthalocyanine as the active layer. Parylene film ... At room temperature, these transistors exhibit p-type conductivity with field-effect ... Keywords. Organic semiconductor; field effect transistor; phthalocyanine; high mobility. ... The evaporation rate was kept at ...

  12. The use of 2N3055 transistor as photosensory in solarymeter

    International Nuclear Information System (INIS)

    Bintoro; Sastroamidjojo, M.S.A.

    1981-01-01

    The characteristics of 2N3055 type transistor used for solarymeters sensor. It can be seen that transistor sensor has more response time. The response to against arrival solar intensity is linear. It can be used for solarymeter sensor after calibrated with pyranometer reference, but not so sensitive for 500 nanometer wavelength. It can be concluded that 2N3055 transistor made by Motrola than the made by R.C.A. because the 2N3055 transistor is more wide and more accurate than the R.C.A. transistor. (author tr.)

  13. [Differences in Subjective Experience Between Unipolar and Bipolar Depression].

    Science.gov (United States)

    Fierro, Marco; Bustos, Andrés; Molina, Carlos

    2016-01-01

    It is important to make distinction between bipolar and unipolar depression because treatment and prognosis are different. Since the diagnosis of the two conditions is purely clinical, find symptomatic differences is useful. Find differences in subjective experience (first person) between unipolar and bipolar depression. Phenomenological-oriented qualitative exploratory study of 12 patients (7 with bipolar depression and 5 with unipolar depression, 3 men and 9 women). We used a semi-structured interview based on Examination of Anomalous Self-Experience (EASE). The predominant mood in bipolar depression is emotional dampening, in unipolar is sadness. The bodily experience in bipolar is of a heavy, tired body; an element that inserts between the desires of acting and performing actions and becomes an obstacle to the movement. In unipolar is of a body that feels more comfortable with the stillness than activity, like laziness of everyday life. Cognition and the stream of consciousness: in bipolar depression, compared with unipolar, thinking is slower, as if to overcome obstacles in their course. There are more difficult to understand what is heard or read. Future perspective: in bipolar depression, hopelessness is stronger and broader than in unipolar, as if the very possibility of hope was lost. Qualitative differences in predominant mood, bodily experience, cognition and future perspective were found between bipolar and unipolar depression. Copyright © 2015 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  14. Screening for bipolar disorders in Spanish-speaking populations: sensitivity and specificity of the Bipolar Spectrum Diagnostic Scale-Spanish Version.

    Science.gov (United States)

    Vázquez, Gustavo Héctor; Romero, Ester; Fabregues, Fernando; Pies, Ronald; Ghaemi, Nassir; Mota-Castillo, Manuel

    2010-01-01

    Bipolar disorder is commonly misdiagnosed, perhaps more so in Latin American and Spanish-speaking populations than in the United States. The Bipolar Spectrum Diagnostic Scale (BSDS) is a 19-item screening instrument designed to assist in screening for all types of bipolar disorder. The authors investigated the sensitivity of a Spanish-language version of the BSDS in a cohort of 65 outpatients with a diagnosis of bipolar disorder, based on a semi-structured interview and Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria. To determine specificity, we assessed a control group of 36 outpatients with diagnosis of unipolar major depressive disorder. The overall sensitivity of the BSDS Spanish version with bipolar disorders types I, II, and NOS was 0.70, which was slightly lower than the sensitivity in the study using the English version of the BSDS (0.76). The specificity was 0.89. When the threshold was decreased from 13 to 12, the sensitivity of the Spanish BSDS increased to 0.76 and specificity dropped to 0.81. The Spanish version of the BSDS is promising as a screening instrument in Spanish-speaking populations. Copyright 2010 Elsevier Inc. All rights reserved.

  15. Improvements in or relating to transistor circuits

    International Nuclear Information System (INIS)

    Richards, R.F.; Williamson, P.W.

    1978-01-01

    This invention relates to transistor circuits and in particular to integrated transistor circuits formed on a substrate of semi-conductor material such as silicon. The invention is concerned with providing integrated circuits in which malfunctions caused by the effects of ionising, e.g. nuclear, radiations are reduced. (author)

  16. Transient Stuttering in Catatonic Bipolar Patients

    Directory of Open Access Journals (Sweden)

    Anthony B. Joseph

    1991-01-01

    Full Text Available Two cases of transient stuttering occurring in association with catatonia and bipolar disorder are described. Affective decompensation has been associated with lateralized cerebral dysfunction, and it is hypothesized that in some bipolar catatonic patients a concomitant disorder of the lateralization of language function may lead to a variety of clinical presentations including aphasia, mutism, and stuttering.

  17. Enhanced transconductance in a double-gate graphene field-effect transistor

    Science.gov (United States)

    Hwang, Byeong-Woon; Yeom, Hye-In; Kim, Daewon; Kim, Choong-Ki; Lee, Dongil; Choi, Yang-Kyu

    2018-03-01

    Multi-gate transistors, such as double-gate, tri-gate and gate-all-around transistors are the most advanced Si transistor structure today. Here, a genuine double-gate transistor with a graphene channel is experimentally demonstrated. The top and bottom gates of the double-gate graphene field-effect transistor (DG GFET) are electrically connected so that the conductivity of the graphene channel can be modulated simultaneously by both the top and bottom gate. A single-gate graphene field-effect transistor (SG GFET) with only the top gate is also fabricated as a control device. For systematical analysis, the transfer characteristics of both GFETs were measured and compared. Whereas the maximum transconductance of the SG GFET was 17.1 μS/μm, that of the DG GFET was 25.7 μS/μm, which is approximately a 50% enhancement. The enhancement of the transconductance was reproduced and comprehensively explained by a physics-based compact model for GFETs. The investigation of the enhanced transfer characteristics of the DG GFET in this work shows the possibility of a multi-gate architecture for high-performance graphene transistor technology.

  18. Metal nanoparticle film–based room temperature Coulomb transistor

    Science.gov (United States)

    Willing, Svenja; Lehmann, Hauke; Volkmann, Mirjam; Klinke, Christian

    2017-01-01

    Single-electron transistors would represent an approach to developing less power–consuming microelectronic devices if room temperature operation and industry-compatible fabrication were possible. We present a concept based on stripes of small, self-assembled, colloidal, metal nanoparticles on a back-gate device architecture, which leads to well-defined and well-controllable transistor characteristics. This Coulomb transistor has three main advantages. By using the scalable Langmuir-Blodgett method, we combine high-quality chemically synthesized metal nanoparticles with standard lithography techniques. The resulting transistors show on/off ratios above 90%, reliable and sinusoidal Coulomb oscillations, and room temperature operation. Furthermore, this concept allows for versatile tuning of the device properties such as Coulomb energy gap and threshold voltage, as well as period, position, and strength of the oscillations. PMID:28740864

  19. Large scale electromechanical transistor with application in mass sensing

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Leisheng; Li, Lijie, E-mail: L.Li@swansea.ac.uk [Multidisciplinary Nanotechnology Centre, College of Engineering, Swansea University, Swansea SA2 8PP (United Kingdom)

    2014-12-07

    Nanomechanical transistor (NMT) has evolved from the single electron transistor, a device that operates by shuttling electrons with a self-excited central conductor. The unfavoured aspects of the NMT are the complexity of the fabrication process and its signal processing unit, which could potentially be overcome by designing much larger devices. This paper reports a new design of large scale electromechanical transistor (LSEMT), still taking advantage of the principle of shuttling electrons. However, because of the large size, nonlinear electrostatic forces induced by the transistor itself are not sufficient to drive the mechanical member into vibration—an external force has to be used. In this paper, a LSEMT device is modelled, and its new application in mass sensing is postulated using two coupled mechanical cantilevers, with one of them being embedded in the transistor. The sensor is capable of detecting added mass using the eigenstate shifts method by reading the change of electrical current from the transistor, which has much higher sensitivity than conventional eigenfrequency shift approach used in classical cantilever based mass sensors. Numerical simulations are conducted to investigate the performance of the mass sensor.

  20. Tunneling field effect transistor technology

    CERN Document Server

    Chan, Mansun

    2016-01-01

    This book provides a single-source reference to the state-of-the art in tunneling field effect transistors (TFETs). Readers will learn the TFETs physics from advanced atomistic simulations, the TFETs fabrication process and the important roles that TFETs will play in enabling integrated circuit designs for power efficiency. · Provides comprehensive reference to tunneling field effect transistors (TFETs); · Covers all aspects of TFETs, from device process to modeling and applications; · Enables design of power-efficient integrated circuits, with low power consumption TFETs.

  1. [Actigraphy in Bipolar Disorder and First Degree Relatives].

    Science.gov (United States)

    Andrade Carrillo, Rommel; Gómez Cano, Sujey; Palacio Ortiz, Juan David; García Valencia, Jenny

    2015-01-01

    Bipolar disorder is a disabling disease that involves a significant economic costs to the health system, making it is essential to investigate possible early predictors such as changes in sleep-wake cycle in high-risk populations. To review the available literature on alterations in the sleep-wake cycle and circadian rhythm in patients with bipolar disorder and their first degree relatives. A literature search was performed in the data bases, Access Medicine, ClinicalKey, EMBASE, JAMA, Lilacs, OVID, Oxford Journals, ScienceDirect, SciELO, APA y PsycNET. Articles in both English and Spanish were reviewed, without limits by study type. Actigraphy is a non-invasive, useful method for assessing sleep-wake cycle disturbances in the active phases of bipolar disorder, and during euthymia periods. Actigraphy showed good sensitivity to predict true sleep, but low specificity, compared with polysomnography. Although studies in bipolar offspring and relatives are scarce, they show sleep changes similar to bipolar patients. Actigraphy may be a good screening tool of sleep/wake cycle in patients with bipolar disorders, because it is economic, non-invasive and sensitive. Longitudinal studies are required to evaluate its potential use as a risk marker. Copyright © 2014 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  2. HIV-infected persons with bipolar disorder are less aware of memory deficits as compared to HIV-infected persons without bipolar disorder

    OpenAIRE

    Blackstone, Kaitlin; Tobin, Alexis; Posada, Carolina; Gouaux, Ben; Grant, Igor; Moore, David J.

    2012-01-01

    Episodic memory deficits are common in HIV infection and bipolar disorder, but patient insight into such deficits remains unclear. Thirty-four HIV-infected individuals without bipolar disorder l(HIV+/BD−) and 47 HIV+ individuals with comorbid bipolar disorder (HIV+/BD+) were administered the Hopkins Verbal Learning Test-Revised and the Brief Visuospatial Memory Test-Revised to examine objective learning/memory functioning. Subjective memory complaints were assessed via the memory subscale of ...

  3. Organic semiconductors for organic field-effect transistors

    International Nuclear Information System (INIS)

    Yamashita, Yoshiro

    2009-01-01

    The advantages of organic field-effect transistors (OFETs), such as low cost, flexibility and large-area fabrication, have recently attracted much attention due to their electronic applications. Practical transistors require high mobility, large on/off ratio, low threshold voltage and high stability. Development of new organic semiconductors is key to achieving these parameters. Recently, organic semiconductors have been synthesized showing comparable mobilities to amorphous-silicon-based FETs. These materials make OFETs more attractive and their applications have been attempted. New organic semiconductors resulting in high-performance FET devices are described here and the relationship between transistor characteristics and chemical structure is discussed. (topical review)

  4. Transistors using crystalline silicon devices on glass

    Science.gov (United States)

    McCarthy, Anthony M.

    1995-01-01

    A method for fabricating transistors using single-crystal silicon devices on glass. This method overcomes the potential damage that may be caused to the device during high voltage bonding and employs a metal layer which may be incorporated as part of the transistor. This is accomplished such that when the bonding of the silicon wafer or substrate to the glass substrate is performed, the voltage and current pass through areas where transistors will not be fabricated. After removal of the silicon substrate, further metal may be deposited to form electrical contact or add functionality to the devices. By this method both single and gate-all-around devices may be formed.

  5. Organic semiconductors for organic field-effect transistors

    Directory of Open Access Journals (Sweden)

    Yoshiro Yamashita

    2009-01-01

    Full Text Available The advantages of organic field-effect transistors (OFETs, such as low cost, flexibility and large-area fabrication, have recently attracted much attention due to their electronic applications. Practical transistors require high mobility, large on/off ratio, low threshold voltage and high stability. Development of new organic semiconductors is key to achieving these parameters. Recently, organic semiconductors have been synthesized showing comparable mobilities to amorphous-silicon-based FETs. These materials make OFETs more attractive and their applications have been attempted. New organic semiconductors resulting in high-performance FET devices are described here and the relationship between transistor characteristics and chemical structure is discussed.

  6. Bipolar explosion models for hypernovae

    International Nuclear Information System (INIS)

    Maeda, Keiichi; Nomoto, Ken'ichi

    2003-01-01

    Bipolar explosion models for hypernovae (very energetic supernovae) are presented. These models provide a favorable situation to explain some unexpected features in observations of hypernovae, e.g., high velocity matter dominated by Fe and low velocity matter dominated by O. The overall abundance of these models gives a good fit, at least qualitatively, to abundances in extremely metal-poor stars. We suggest hypernovae be driven by bipolar jets and contribute significantly to the early Galactic chemical evolution

  7. Evaluation of bipolar pulse generator for high-purity pulsed ion beam

    International Nuclear Information System (INIS)

    Ito, H.; Kitamura, I.; Masugata, K.

    2008-01-01

    A new type of pulsed ion beam accelerator named 'bipolar pulse accelerator (BPA)' has been proposed in order to improve the purity of intense pulsed ion beams. To confirm the principle of the BPA, we developed a bipolar pulse generator, which consists of a Marx generator and a pulse forming line (PFL) with a rail gap switch on its end. In this article, we report the experimental results of the bipolar pulse and evaluate the electrical characteristics of the bipolar pulse generator. When the bipolar pulse generator was operated at 70% of the full charge condition of the PEL, the bipolar pulse with the first (-138 kV, 72 ns) and the second pulse (+130 kV, 70 ns) was successfully obtained. The evaluation of the electrical characteristics indicates that the developed generator can produce the bipolar pulse with fast rise time and sharp reversing time. At present the bipolar pulse generator is installed in the B y type magnetically insulated ion diode and we carry out the experiment on the production of an intense pulsed ion beam by the bipolar pulse accelerator. (author)

  8. Study of Attention Deficit in Patients with Schizophrenia and Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    SM Kafi

    2013-05-01

    Full Text Available Abstract Background & aim: Attention deficit has significant effect on the life of patients suffering from schizophrenia and bipolar disorder. The aim of this study was to assess the attention deficit in patients with schizophrenia. Methods: In the present post-hoc study, 132 patients with schizophrenia and bipolar disorder were selected via non-randomized sampling at Shafa Hospital (Rasht, Iran and then divided into four equal groups: chronic schizophrenia patients, first-episode patients, chronic bipolar patients, and first-episode bipolar patients. Thirty-three healthy individuals were selected as the control group. Subjects were evaluated by Stroop color-word test. The gathered Data were analyzed by one-way ANOVA. Results: Attention deficit among chronic schizophrenics and patients suffering from bipolar disease was higher than the control group (p <1. Chronic schizophrenic patients compared with schizophrenia bipolar disease and first round schizophrenia showed more attention deficit. There was no significant difference among the first bipolar disease and schizophrenia, bipolar disorder, as well as the first round schizophrenia (p<0.05. Conclusion: Attention deficit is more severe in schizophrenic patients than bipolar disorder, and chronicity is more effective in schizophrenic patients. Key words: Attention, Schizophrenia, Chronicity

  9. Antidepressant monotherapy in pre-bipolar depression; predictive value and inherent risk.

    Science.gov (United States)

    O'Donovan, Claire; Garnham, Julie S; Hajek, Tomas; Alda, Martin

    2008-04-01

    To identify specific treatment-emergent symptoms in response to antidepressant therapy in depression preceding bipolar disorder. Retrospective chart review of response to antidepressants in "pre-bipolar" depression, compared to a matched unipolar sample. Family history of completed suicide (p=0.0003) and bipolar disorder (p=0.004) were more common in the pre-bipolar subgroup. Earlier age of onset of diagnosed depression (p=0.005) as well as even earlier episodes of untreated retrospectively diagnosed major depression (p<0.0001) were associated with a future bipolar course. The pre-bipolar group was less likely to respond to antidepressant treatment (p=0.009). Treatment-emergent "mixed" symptoms (two or more symptoms of DSM IV mania, mood lability, irritability/rage with co-existing depression) and in particular, "serious symptoms" (treatment emergent or increased agitation, rage or suicidality) occurred more commonly in the bipolar group. The two variables that best accounted for the between-group differences in logistic regression, were early age at first symptoms of depression and treatment-emergent agitation. Family history of completed suicide and/or bipolar disorder, early onset of depressive symptoms as well as treatment-emergent "mixed" symptoms are common in depression preceding the diagnosis of bipolar disorder.

  10. Progress and challenges in bipolar lead-acid battery development

    Science.gov (United States)

    Bullock, Kathryn R.

    1995-05-01

    Bipolar lead-acid batteries have higher power densities than any other aqueous battery system. Predicted specific powers based on models and prototypes range from 800 kW/kg for 100 ms discharge times to 1.6 kW/kg for 10 s. A 48 V automotive bipolar battery could have 2 1/2 times the cold cranking rate of a monopolar 12 V design in the same size. Problems which have precluded the development of commercial bipolar designs include the instability of substrate materials and enhanced side reactions. Design approaches include pseudo-bipolar configurations, as well as true bipolar designs in planar and tubular configurations. Substrate materials used include lead and lead alloys, carbons, conductive ceramics, and tin-oxide-coated glass fibers. These approaches are reviewed and evaluated.

  11. Microwave components for cellular portable radiotelephone

    Science.gov (United States)

    Muraguchi, Masahiro; Aikawa, Masayoshi

    1995-09-01

    Mobile and personal communication systems are expected to represent a huge market for microwave components in the coming years. A number of components in silicon bipolar, silicon Bi-CMOS, GaAs MESFET, HBT and HEMT are now becoming available for system application. There are tradeoffs among the competing technologies with regard to performance, cost, reliability and time-to-market. This paper describes process selection and requirements of cost and r.f. performances to microwave semiconductor components for digital cellular and cordless telephones. Furthermore, new circuit techniques which were developed by NTT are presented.

  12. Are rates of pediatric bipolar disorder increasing?

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Vradi, Eleni; Andersen, Per Kragh

    2014-01-01

    Studies from the USA suggest that rates of pediatric bipolar disorder have increased since the mid-90s, but no study outside the USA has been published on the rates of pediatric bipolar disorder. Further, it is unclear whether an increase in rates reflects a true increase in the illness or more...... diagnostic attention. Using nationwide registers of all inpatients and outpatients contacts to all psychiatric hospitals in Denmark, we investigated (1) gender-specific rates of incident pediatric mania/bipolar disorder during a period from 1995 to 2012, (2) whether age and other characteristics...... for pediatric mania/bipolar disorder changed during the calendar period (1995 to 2003 versus 2004 to 2012), and (3) whether the diagnosis is more often made at first psychiatric contact in recent time compared to earlier according to gender. Totally, 346 patients got a main diagnosis of a manic episode (F30...

  13. Cognitive and psychosocial impairment in remitted bipolar patients

    Directory of Open Access Journals (Sweden)

    Flávia Moreira Lima

    2015-07-01

    Full Text Available There is growing evidence showing that bipolar disorder is associated with persistent cognitive deficits. However, the exact meaning and impact of cognitive deficits in bipolar disorder is still not entirely known, even though they have been associated with poor psychosocial functioning. This study aims to summarize cognitive and psychosocial functioning findings of remitted bipolar patients. We conducted an extensive Medline search of the published English literature for the period January 2000– March 2014 using a variety of search terms to find relevant articles. Bibliographies of retrieved papers were further analysed for publications of interest. Our results showed that: (1 all mood states of bipolar disorder are associated with cognitive impairment. However, the euthymic state is associated with less impairment than the other states; (2 there is a strong association between clinical factors (i.e, duration of illness, number of episodes, residual mood symptoms, comorbidities and cognitive impairment in euthymic bipolar patients, although these factors do not account fully for these deficits; (3 cognitive deficits, in particular, verbal learning and executive dysfunctions may contribute to poor functioning. In conclusion, our review suggests that cognitive deficits are strongly associated with mood episodes; such deficits persist, in lower degree, during remission. Impairment on cognitive performance may explain, in part, poor long–term functioning in remitted bipolar patients. It highlights that psychosocial interventions in combination with pharmacotherapy should be considered to improve cognition and enhance the level of functioning. Therefore, studies assessing the efficacy of novel strategies focused on cognitive and functional status are an important area of future investigation in bipolar disorder.

  14. Family Functioning and the Course of Adolescent Bipolar Disorder

    Science.gov (United States)

    Sullivan, Aimee E.; Judd, Charles M.; Axelson, David A.; Miklowitz, David J.

    2012-01-01

    The symptoms of bipolar disorder affect and are affected by the functioning of family environments. Little is known, however, about the stability of family functioning among youth with bipolar disorder as they cycle in and out of mood episodes. This study examined family functioning and its relationship to symptoms of adolescent bipolar disorder,…

  15. Simulaci??n y modelado de transistores MOS de doble puerta

    OpenAIRE

    Cartujo Cassinello, Pedro

    2000-01-01

    En este trabajo se hace un estudio del transistor MOS de doble puerta analizando las posibles ventajas de esta nueva estructura frene al transistor convencional y el transistor MOS SOI de puerta simple. Para ello se ha analizado una secci??n transversal de un transistor MOS de doble puerta de canal N, con el fin de examinar detalladamente las peculiaridades de la distribuci??n de electrones con una amplia variedad de valores de todos los par??mentros tecnol??gicos y condiciones de operaci??n,...

  16. Neurocognition and psychosocial functioning in adolescents with bipolar disorder.

    Science.gov (United States)

    Best, Michael W; Bowie, Christopher R; Naiberg, Melanie R; Newton, Dwight F; Goldstein, Benjamin I

    2017-01-01

    Adults with bipolar disorder demonstrate significantly poorer psychosocial functioning and neurocognition compared to controls. In adult bipolar disorder neurocognition predicts a substantial portion of variance in functioning. Adolescents with bipolar disorder have reducedpsychosocial functioning, but less is known about neurocognitive impairments, and no studies have examined the relationship between neurocognition and functioning in an adolescent sample. 38 adolescents with bipolar disorder and 49 healthy controls under 20 years of age completed assessments of psychosocial functioning, neurocognitive ability, and psychiatric symptoms. Adolescents with bipolar disorder had significantly poorer psychosocial functioning in domains of daily activities, social functioning, and satisfaction with functioning, psadolescent sample with bipolar disorder experiences significantly poorer neurocognitive and psychosocial functioning compared to controls; however, psychosocial functioning appears to be more strongly related to mood symptoms than to neurocognition. Future work is needed to delineate the time course of neurocognitive functioning and its relation to psychosocial functioning across the course of illness. Adolescence may provide an ideal time for cognitive enhancement and intensive psychosocial intervention. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Characteristics of stress-coping behaviors in patients with bipolar disorders.

    Science.gov (United States)

    Moon, Eunsoo; Chang, Jae Seung; Choi, Sungwon; Ha, Tae Hyon; Cha, Boseok; Cho, Hyun Sang; Park, Je Min; Lee, Byung Dae; Lee, Young Min; Choi, Yoonmi; Ha, Kyooseob

    2014-08-15

    Appropriate stress-coping strategies are needed to improve the outcome in the treatment of bipolar disorders, as stressful life events may aggravate the course of the illness. The aim of this study was to compare stress-coping behaviors between bipolar patients and healthy controls. A total of 206 participants comprising 103 bipolar patients fulfilling the Diagnostic and Statistical Manual for Axis I disorder fourth edition (DSM-IV) diagnostic criteria for bipolar I and II disorders and controls matched by age and sex were included in this study. Stress-coping behaviors were assessed using a 53-item survey on a newly-designed behavioral checklist. The characteristics of stress-coping behaviors between the two groups were compared by using t-test and factor analysis. Social stress-coping behaviors such as 'journey', 'socializing with friends', and 'talking something over' were significantly less frequent in bipolar patients than controls. On the other hand, pleasurable-seeking behaviors such as 'smoking', 'masturbation', and 'stealing' were significantly more frequent in bipolar patients than controls. These results suggest that bipolar patients may have more maladaptive stress-coping strategies than normal controls. It is recommended to develop and apply psychosocial programs to reduce maladaptive stress-coping behaviors of bipolar patients. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. The seroprevalence of antithyroid peroxidase antibodies in bipolar families and bipolar twins: results from two longitudinal studies.

    Science.gov (United States)

    Snijders, G; de Witte, L; Mesman, E; Kemner, S; Vonk, R; Brouwer, R; Nolen, W A; Drexhage, H A; Hillegers, M H J

    2017-12-01

    Previous studies of our group among bipolar offspring and bipolar twins showed significant higher prevalence's and levels of antithyroid peroxidase antibodies (TPO-Abs) in offspring and co-twins (without a mood disorder) compared to controls, suggesting that TPO-Abs might be considered as vulnerability factor (trait marker) for BD development. Here we elucidate, in the same cohorts, but now after 12- and 6-year follow-up, whether TPO-abs should be considered as a 'trait' marker for BD. The present study aims to investigate whether TPO-Abs (1) are stable over time, (2) are associated with lithium-exposure, (3) share a common genetic background with BD and are related to psychopathology. In bipolar offspring and twins, the prevalence of TPO-Abs is stable over time (r s  = .72 p bipolar offspring (10,4% versus 4%) and higher TPO-abs titers were still present in co-twins of bipolar cases compared to control twins [mean 1.06 IU/ml (SD .82) versus mean .82 IU/ml (SD .67)], although statistical significance was lost. Although our results show a trend toward an increased inherited risk of the co-occurrence of BD and thyroid autoimmunity, large-scale studies can only draw final conclusions. Nationwide epidemiological and GWAS studies reach such numbers and support the view of a possible common (autoimmune) etiology of severe mood disorders and chronic recurrent infections and autoimmunity, including thyroid autoimmunity.

  19. História da caracterização nosológica do transtorno bipolar History of the nosologic characterization of bipolar disorder

    Directory of Open Access Journals (Sweden)

    José Alberto Del-Porto

    2005-01-01

    Full Text Available Os autores apresentam uma sintética revisão da história da doença bipolar, a partir de Araeteus da Capadócia até os tempos atuais. O conceito moderno de doença bipolar foi iniciado na França, com os trabalhos de Falret (1851 e Baillarger (1856. Os conceitos seminais de Emil Kraepelin mudaram as bases da nosologia psiquiátrica, e o seu conceito unitário a respeito da "insanidade maníaco-depressiva" foi amplamente aceito e adotado. As idéias de Kraepelin e Weigandt constituíram-se na pedra angular para sua concepção unitária da doença maníaco-depressiva. Depois de Kraepelin, no entanto, as idéias de Kleist e Leonhard, na Alemanha, e o trabalho de Angst, Perris e Winokur enfatizaram a distinção entre as formas unipolar e bipolar da depressão. Mais recentemente a ênfase mudou novamente para o espectro bipolar, que se estende até os limites dos temperamentos normais (Akiskal e colaboradores. Finalizando, os autores sumarizam as controvérsias quanto à nosologia do transtorno bipolar e suas fronteiras com a esquizofrenia, os quadros esquizoafetivos e as chamadas psicoses ciclóides.The authors review briefly the history of bipolar disorder from Araeteus of Cappadocia to our times. The modern concept of bipolar disorder was built in France, through the work of Falret (1851 and Baillarger (1854. The pivotal concepts of Emil Kraepelin changed the basis of psychiatric nosology, and Kraepelin's unitary concept of manic-depressive insanity was largely accepted. Kraepelin and Weigandt's ideas on mixed states were a cornerstone to this unitary concept. After Kraepelin however, the ideas of Kleist and Leonhard, in Germany, and the work of Angst, Perris and Winokur emphasized the distinction between unipolar and bipolar forms of depression. More recently the emphasis changed again to the bipolar spectrum, which expanded to the borders of the normal temperaments (Akiskal and co-workers. At the end the authors summarize the controversies

  20. Diffusion pipes at PNP switching transistors

    International Nuclear Information System (INIS)

    Sachelarie, D.; Postolache, C.; Gaiseanu, F.

    1976-01-01

    The appearance of the ''diffusion pipes'' greatly affects the fabrication of the PNP high-frequency/very-fast-switching transistors. A brief review of the principal problems connected to the presence of these ''pipes'' is made. A research program is presented which permitted the fabrication of the PNP switching transistors at ICCE-Bucharest, with transition frequency fsub(T) = 1.2 GHz and storage time tsub(s) = 4.5 ns. (author)