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1

GaAs vapor-grown bipolar transistors.  

NASA Technical Reports Server (NTRS)

Discussion of an approach for the fabrication of high-temperature GaAs transistors which is centered on the preparation of n-p-n three-layered structures entirely by a vapor-phase growth technique, as described by Tietjen and Amick (1966). The low growth temperature of approximately 750 C is thought to reduce contamination during crystal growth and to contribute to the reasonably high minority-carrier lifetimes obtained for the vapor-grown p-n junctions. The fact that impurity concentrations and layer thicknesses can be precisely controlled for epitaxial layers as thin as 1 micrometer is an important feature of this growth technique.

Nuese, C. J.; Gannon, J. J.; Dean, R. H.; Gossenberger, H. F.; Enstrom, R. E.

1972-01-01

2

Analysis of GaAs Heterojunction Bipolar Transistor ICs using Passive Detection of Radiative Recombination  

Microsoft Academic Search

Passive detection of the radiative recombination of electrons in the p-type GaAs base of active heterojunction bipolar transistors (HBTs) has been utilised to demonstrate a non-invasive analytical probing technique, compatible with conventional wafer probers, which produces TV pictures of ICs with the active HBTs hiqhlighted. Failure modes, such as in-operative tail current sources and latched stages, were identified in ECL

C G Eddison; R C Hayes; S Gurden; R C Goodfellow

1987-01-01

3

Fabrication and high temperature characteristics of ion-implanted GaAs bipolar transistors and ring-oscillators  

NASA Technical Reports Server (NTRS)

Ion implantation techniques that permit the reproducible fabrication of bipolar GaAs integrated circuits are studied. A 15 stage ring oscillator and discrete transistor were characterized between 25 and 400 C. The current gain of the transistor was found to increase slightly with temperature. The diode leakage currents increase with an activation energy of approximately 1 eV and dominate the transistor leakage current 1 sub CEO above 200 C. Present devices fail catastrophically at about 400 C because of Au-metallization.

Doerbeck, F. H.; Yuan, H. T.; Mclevige, W. V.

1981-01-01

4

Ion bipolar junction transistors  

PubMed Central

Dynamic control of chemical microenvironments is essential for continued development in numerous fields of life sciences. Such control could be achieved with active chemical circuits for delivery of ions and biomolecules. As the basis for such circuitry, we report a solid-state ion bipolar junction transistor (IBJT) based on conducting polymers and thin films of anion- and cation-selective membranes. The IBJT is the ionic analogue to the conventional semiconductor BJT and is manufactured using standard microfabrication techniques. Transistor characteristics along with a model describing the principle of operation, in which an anionic base current amplifies a cationic collector current, are presented. By employing the IBJT as a bioelectronic circuit element for delivery of the neurotransmitter acetylcholine, its efficacy in modulating neuronal cell signaling is demonstrated. PMID:20479274

Tybrandt, Klas; Larsson, Karin C.; Richter-Dahlfors, Agneta; Berggren, Magnus

2010-01-01

5

Bipolar Transistor Based on Graphane  

NASA Astrophysics Data System (ADS)

Graphane is a semiconductor with an energy gap, obtained from hydrogenation of the two-dimensional grapheme sheet. Together with the two-dimensional geometry, unique transport features of graphene, and possibility of doping graphane, p and n regions can be defined so that p-n junctions become feasible with small reverse currents. Our recent analysis has shown that an ideal I-V characteristic for this type of junctions may be expected. Here, we predict the behavior of bipolar juncrion transistors based on graphane. Profiles of carriers and intrinsic parameters of the graphane transistor are calculated and discussed.

Gharekhanlou, B.; Tousaki, S. B.; Khorasani, S.

2010-11-01

6

A comparison of the GaAs MESFET and the AlGaAs/GaAs heterojunction bipolar transistor for power microwave amplification  

NASA Astrophysics Data System (ADS)

The study is normalized by constraining the devices to a specific application: 1-W RF output power at 10 GHz. It is shown that the power gain and thermal resistance are higher and input impedances lower for the heterojunction bipolar transistor (HBT). Because of the higher thermal resistance, the operating temperature is significantly higher for the HBT, limiting the CW power output from the device. If the device area is increased to reduce the power density, then the input impedance (common emitter) is proportionally reduced, making input matching much more difficult.

Long, Stephen I.

1989-07-01

7

Voltage regulator for battery power source. [using a bipolar transistor  

NASA Technical Reports Server (NTRS)

A bipolar transistor in series with the battery as the control element also in series with a zener diode and a resistor is used to maintain a predetermined voltage until the battery voltage decays to very nearly the predetermined voltage. A field effect transistor between the base of the bipolar transistor and a junction between the zener diode and resistor regulates base current of the bipolar transistor, thereby regulating the conductivity of the bipolar transistor for control of the output voltage.

Black, J. M. (inventor)

1979-01-01

8

Vertical Bipolar Charge Plasma Transistor with Buried Metal Layer  

NASA Astrophysics Data System (ADS)

A self-aligned vertical Bipolar Charge Plasma Transistor (V-BCPT) with a buried metal layer between undoped silicon and buried oxide of the silicon-on-insulator substrate, is reported in this paper. Using two-dimensional device simulation, the electrical performance of the proposed device is evaluated in detail. Our simulation results demonstrate that the V-BCPT not only has very high current gain but also exhibits high BVCEO . fT product making it highly suitable for mixed signal high speed circuits. The proposed device structure is also suitable for realizing doping-less bipolar charge plasma transistor using compound semiconductors such as GaAs, SiC with low thermal budgets. The device is also immune to non-ideal current crowding effects cropping up at high current densities.

Nadda, Kanika; Kumar, M. Jagadesh

2015-01-01

9

Vertical Bipolar Charge Plasma Transistor with Buried Metal Layer  

PubMed Central

A self-aligned vertical Bipolar Charge Plasma Transistor (V-BCPT) with a buried metal layer between undoped silicon and buried oxide of the silicon-on-insulator substrate, is reported in this paper. Using two-dimensional device simulation, the electrical performance of the proposed device is evaluated in detail. Our simulation results demonstrate that the V-BCPT not only has very high current gain but also exhibits high BVCEO · fT product making it highly suitable for mixed signal high speed circuits. The proposed device structure is also suitable for realizing doping-less bipolar charge plasma transistor using compound semiconductors such as GaAs, SiC with low thermal budgets. The device is also immune to non-ideal current crowding effects cropping up at high current densities. PMID:25597295

Nadda, Kanika; Kumar, M. Jagadesh

2015-01-01

10

Vertical bipolar charge plasma transistor with buried metal layer.  

PubMed

A self-aligned vertical Bipolar Charge Plasma Transistor (V-BCPT) with a buried metal layer between undoped silicon and buried oxide of the silicon-on-insulator substrate, is reported in this paper. Using two-dimensional device simulation, the electrical performance of the proposed device is evaluated in detail. Our simulation results demonstrate that the V-BCPT not only has very high current gain but also exhibits high BVCEO · fT product making it highly suitable for mixed signal high speed circuits. The proposed device structure is also suitable for realizing doping-less bipolar charge plasma transistor using compound semiconductors such as GaAs, SiC with low thermal budgets. The device is also immune to non-ideal current crowding effects cropping up at high current densities. PMID:25597295

Nadda, Kanika; Kumar, M Jagadesh

2015-01-01

11

Polyphosphonium-based ion bipolar junction transistors.  

PubMed

Advancements in the field of electronics during the past few decades have inspired the use of transistors in a diversity of research fields, including biology and medicine. However, signals in living organisms are not only carried by electrons but also through fluxes of ions and biomolecules. Thus, in order to implement the transistor functionality to control biological signals, devices that can modulate currents of ions and biomolecules, i.e., ionic transistors and diodes, are needed. One successful approach for modulation of ionic currents is to use oppositely charged ion-selective membranes to form so called ion bipolar junction transistors (IBJTs). Unfortunately, overall IBJT device performance has been hindered due to the typical low mobility of ions, large geometries of the ion bipolar junction materials, and the possibility of electric field enhanced (EFE) water dissociation in the junction. Here, we introduce a novel polyphosphonium-based anion-selective material into npn-type IBJTs. The new material does not show EFE water dissociation and therefore allows for a reduction of junction length down to 2??m, which significantly improves the switching performance of the ion transistor to 2 s. The presented improvement in speed as well the simplified design will be useful for future development of advanced iontronic circuits employing IBJTs, for example, addressable drug-delivery devices. PMID:25553192

Gabrielsson, Erik O; Tybrandt, Klas; Berggren, Magnus

2014-11-01

12

Perpendicular transport in superlattice bipolar transistors (SBT)  

NASA Astrophysics Data System (ADS)

Diffusion-limited electron transport in superlattices is studied by gain measurements on heterojunction bipolar transistors with a {GaAs}/{GaAlAs} superlattice base. In the case of thin barriers, Bloch conduction is observed, while hopping between localized levels prevails for large barriers. A transition occurs between these two regimes, localization being achieved when the energy broadening induced by the electron-phonon coupling added to the disorder due to imperfect growth is of the order of the miniband width. This interpretation is supported by temperature dependence measurements of the perpendicular mobilities in relation with theoretical calculations of these mobilities.

Sibille, A.; Palmier, J. F.; Minot, C.; Harmand, J. C.; Dubon-Chevallier, C.

13

Single-event burnout of epitaxial bipolar transistors  

SciTech Connect

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.

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

1998-12-01

14

Experimental demonstration of a magnetic bipolar junction transistor E. Johnston-Halperin*a  

E-print Network

Experimental demonstration of a magnetic bipolar junction transistor E. Johnston-Halperin*a , M. E of a magnetic base layer to a bipolar junction transistor has the potential to serve as an exceptionally-doped (Ga,Mn)As layer into the p region of an n-p-n III-As heterojunction bipolar transistor. These proof

Flatte, Michael E.

15

Heterojunction bipolar transistor technology for data acquisition and communication  

NASA Technical Reports Server (NTRS)

Heterojunction Bipolar Transistor (HBT) technology has emerged as one of the most promising technologies for ultrahigh-speed integrated circuits. HBT circuits for digital and analog applications, data conversion, and power amplification have been realized, with speed performance well above 20 GHz. At Rockwell, a baseline AlGaAs/GaAs HBT technology has been established in a manufacturing facility. This paper describes the HBT technology, transistor characteristics, and HBT circuits for data acquisition and communication.

Wang, C.; Chang, M.; Beccue, S.; Nubling, R.; Zampardi, P.; Sheng, N.; Pierson, R.

1992-01-01

16

Proton and gamma ray induced gain degradation in bipolar transistor  

NASA Astrophysics Data System (ADS)

This paper describes the results of the effect of 24 MeV proton and (CO)-C-60 gamma-irradiation on the collector characteristic., and forward current gain of commercial bipolar transistor (npn 2N2219A). The transistor has been exposed to these radiations in the biased condition and the collector characteristics and forward current gain have been measured as a function of proton fluence and gamma-dose. The observation is that both the proton and gamma-irradiation induce significant gain degradation in the transistor. The results are discussed in terms of displacement damage produced by energetic protons and gamma-radiation in the bulk of the semiconductor.

Kulkarni, S. R.; Sarma, A.; Joshi, G. R.; Ravindra, M.; Damle, R.

2003-09-01

17

THz Bipolar Transistor Circuits: Technical Feasibility, Technology Development,  

E-print Network

THz Bipolar Transistor Circuits: Technical Feasibility, Technology Development, Integrated Circuit-gain cutoff frequencies of 1-3 THz. High bandwidths are obtained by scaling; the critical limits for the 64 nm scaling geneation (1 THz f, 2 THz fmax) have been developed. We here examine the high

Rodwell, Mark J. W.

18

Silicon carbide and silicon carbide:germanium heterostructure bipolar transistors  

E-print Network

Silicon carbide and silicon carbide:germanium heterostructure bipolar transistors K. J. Roe,a) G HBTs based on silicon carbide SiC and a silicon carbide:germanium SiC:Ge alloy. The SiC:Ge base alloy: 10.1063/1.1358851 Silicon carbide has garnered considerable attention as a promising material for use

Kolodzey, James

19

Bipolar Transistors Can Detect Charge in Electrostatic Experiments  

ERIC Educational Resources Information Center

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…

Dvorak, L.

2012-01-01

20

Demonstration and properties of a planar heterojunction bipolar transistor with lateral current flow  

NASA Astrophysics Data System (ADS)

The authors present fabrication techniques and device performance for a novel transistor structure, the lateral heterojunction bipolar transistor. The lateral heterojunctions are formed by impurity-induced disordering of a GaAs base layer sandwiched between two AlGaAs layers. These transistor structures exhibit current gains of 14 for base widths of 0.74 micron. Transistor action in this device occurs parallel to the surface of the device structure. The active base region of the structure is completely submerged, resulting in a reduction of surface recombination as a mechanism for gain reduction in the device. Impurity-induced disordering is used to widen the bandgap of the alloy in the emitter and collector, resulting in an improvement of the emitter injection efficiency. Since the device is based entirely on a surface diffusion process, the device is completely planar and has no steps involving etching of the III-V alloy material. These advantages lead this device to be considered as a candidate for optoelectronic integration applications. The transistor device functions as a buried heterostructure laser, with a threshold current as low as 6 mA for a 1.4-micron stripe.

Thornton, Robert L.; Mosby, William J.; Chung, Harlan F.

1989-10-01

21

AlGaAs/GaAs heterojunction bipolar transistors with heavily C-doped base layers grown by flow-rate modulation epitaxy  

NASA Astrophysics Data System (ADS)

AlGaAs/GaAs heterojunction bipolar transistors are fabricated using carbon-doped p-type GaAs base regions grown for the first time by flow-rate modulation epitaxy. Because of the much smaller diffusion coefficient of carbon atoms in GaAs than that of beryllium and other p-type impurities, sharp impurity profiles are achieved. The heterojunction bipolar transistors exhibited high current gains up to 40 for a base layer width of 150 nm and base doping of 2.4 x 10 to the 19th /cu cm. The electron lifetime in heavily carbon-doped GaAs layers is considerably long, indicating favorable quality of heavily carbon-doped layers.

Makimoto, Toshiki; Kobayashi, Naoki; Ito, Hiroshi; Ishibashi, Tadao

1989-01-01

22

A New Merged BipolarMOS Transistor in a Silicon on Insulator Structure  

Microsoft Academic Search

A new metal-oxide-silicon (MOS)\\/bipolar merged transistorstructure in a silicon on insulator (SOI), which has a MOS structurewith a built-in bipolar mechanism, is proposed. The transistor has aframe of a metal-oxide-silicon field-effect-transistor (MOSFET) having the gate at the bottom. A vertical bipolar transistor is built in thedrain region by introducing an opposite-type impurity through apolycrystalline silicon buffer layer. Implementation of the

Yue-sheng Zheng; Tanemasa Asano

1999-01-01

23

Bipolar transistor scaling for minimum switching delay and energy dissipation  

Microsoft Academic Search

A novel figure-of-merit to guide in the scaling of high-speed bipolar transistors is proposed. A method is described to relate the gate delay of a ring-oscillator to measurable device parameters analytically. The closed-form solution for an unloaded ECL (emitter coupled logic) gate agrees very well with published data of the past several years and with the results of circuit simulation.

J. M. C. Stork

1988-01-01

24

Insulated gate bipolar transistor (IGBT) modeling using IG-SPICE  

Microsoft Academic Search

A physics-based model for the insulated gate bipolar transistor (IGBT) is implemented into the widely available circuit simulation package IG-SPICE. Based on analytical equations describing the semiconductor-physics, the model accurately describes the nonlinear junction capacitances, moving boundaries, recombination, and carrier scattering, and effectively predicts the device conductivity modulation. In this paper, the procedure used to incorporate the model into IG-SPICE

C. S. Mitter; A. R. Hefner; D. Y. Chen; F. C. Lee

1994-01-01

25

A gallium phosphide high-temperature bipolar junction transistor  

Microsoft Academic Search

Preliminary results are reported on the development of a high-temperature (> 350°C) gallium phosphide bipolar junction transistor (BJT) for goethermal and other energy applications. This four-layer p\\/sup +\\/n⁻pp\\/sup +\\/ structure was fromed by liquid phase epitaxy using a supercooling technique to insure uniform nucleation of the thin layers. Magnesium was used as the p-type dopant to avoid excessive out-diffusion into

T. E. Zipperian; L. R. Dawson; R. J. Caffin

1981-01-01

26

ESD robust bipolar transistors with variable trigger and sustaining voltages  

Microsoft Academic Search

A new pseudo-vertical integrated npn bipolar transistor with variable sustaining and trigger voltages is presented in this paper. It is shown that the sustaining voltage can be tuned to obtain the required high value. These devices are realized in a junction isolated (JI) mixed-signal power BiCMOS technology with maximum breakdown voltage requirements in excess of 60V. The ESD robustness of

S. Pendharkar; P. Hower; R. Steinhofer

2003-01-01

27

Investigation of the tunneling emitter bipolar transistor as spin-injector into silicon  

E-print Network

In this thesis is discussed the tunneling emitter bipolar transistor as a possible spin-injector into silicon. The transistor has a metallic emitter which as a spin-injector will be a ferromagnet. Spin-polarized electrons ...

Van Veenhuizen, Marc Julien

2010-01-01

28

InP/In0.53Ga0.47As/InP Double Heterojunction Bipolar Transistors on a GaAs Substrate Using InP Metamorphic Buffer Layer  

E-print Network

P Metamorphic Buffer Layer Y.M. Kim, M. Dahlstrom, S. Lee, M.J.W. Rodwell, A.C. Gossard Double heterojunction metamorphic growth of InP-based DHBTs on GaAs substrates [4]. Here we report InP-based DHBTs grown on GaAs using InP as the metamorphic buffer layer. While AlGaAsSb and InAlAs have been explored

Rodwell, Mark J. W.

29

Current gain in bipolar transistors with a field plate over the base surface  

E-print Network

Current gain in bipolar transistors with a field plate over the base surface V. Anantharam and K.N. Bhat Indexing terms: Bipolar transistors, Analogue simulation, Carrier lifetime, Minority carriers an electrolytic tank analogue and it is shown that the presence of a proper field plate extending from

Anantharam, Venkat

30

THZ INDIUM PHOSPHIDE BIPOLAR TRANSISTOR TECHNOLOGY M. J. W. Rodwell1  

E-print Network

THZ INDIUM PHOSPHIDE BIPOLAR TRANSISTOR TECHNOLOGY M. J. W. Rodwell1 , J. Rode1 , H.W. Chiang1 , P3 , Thousand Oaks, CA. Abstract -- Scaling laws and limits of THz indium Phosphide heterojunction bipolar transistors (HBTs) are presented. The primary limits to scaling through the 32 nm / 3 THz node

Rodwell, Mark J. W.

31

New Silicon Carbide Schottky-gate Bipolar Mode Field Effect Transistor (SiC SBMFET)  

E-print Network

New Silicon Carbide Schottky-gate Bipolar Mode Field Effect Transistor (SiC SBMFET) without PN. In this paper, we propose a novel Schottky-gate BMFET (SBMFET) using P- type 4H Silicon-Carbide 13,41, a wide, Silicon Carbide, Field effect transistor, Simulation. I. INTRODUCTION TH E BMFET operates in bipolar mode

Kumar, M. Jagadesh

32

Single-event burnout of power bipolar junction transistors  

SciTech Connect

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.

Titus, J.L. (Naval Weapons Support Center, Crane, IN (United States)); Johnson, G.H.; Schrimpf, R.D.; Galloway, K.F. (Arizona Univ., Tucson, AZ (United States). Dept. of Electrical and Computer Engineering)

1991-12-01

33

Hardening measures for bipolar transistors against microwave-induced damage  

NASA Astrophysics Data System (ADS)

In the present paper we study the influences of the bias voltage and the external components on the damage progress of a bipolar transistor induced by high-power microwaves. The mechanism is presented by analyzing the variation in the internal distribution of the temperature in the device. The findings show that the device becomes less vulnerable to damage with an increase in bias voltage. Both the series diode at the base and the relatively low series resistance at the emitter, Re, can obviously prolong the burnout time of the device. However, Re will aid damage to the device when the value is sufficiently high due to the fact that the highest hot spot shifts from the base-emitter junction to the base region. Moreover, the series resistance at the base Rb will weaken the capability of the device to withstand microwave damage.

Chai, Chang-Chun; Ma, Zhen-Yang; Ren, Xing-Rong; Yang, Yin-Tang; Zhao, Ying-Bo; Yu, Xin-Hai

2013-06-01

34

SITCAP -- A simulator of bipolar transistors for computer-aided circuit analysis programs  

Microsoft Academic Search

A fast computer program for the calculation of the para-meterset of circuit models for bipolar transistors, based on processing data, will be presented. Program makes use of a new transport theory permitting accurate current gain prediction.

H. J. DeMan; R. Mertens

1973-01-01

35

The impact of non-equilibrium transport on breakdown and transit time in bipolar transistors  

Microsoft Academic Search

Impact ionization and velocity overshoot in the base-collector junction of bipolar transistors are studied using Monte Carlo simulation and the hydrodynamic energy-balance equation. For advanced bipolar transistors, the carrier energy lags the electric field; therefore, the maximum impact ionization rate occurs deep into the junction. A simplified solution of the energy-balance equation can accurately model this nonlocal behavior. Excellent agreement

E. F. Crabbe; J. M. C. Stork; G. Baccarani; M. V. Fischetti; S. E. Laux

1990-01-01

36

Gallium phosphide high-temperature bipolar junction transistor  

SciTech Connect

Preliminary results are reported on the development of a high-temperature (> 350/sup 0/C) gallium phosphide bipolar junction transistor (BJT) for goethermal and other energy applications. This four-layer p/sup +/n/sup -/pp/sup +/ structure was fromed by liquid phase epitaxy using a supercooling technique to insure uniform nucleation of the thin layers. Magnesium was used as the p-type dopant to avoid excessive out-diffusion into the lightly doped base. By appropriate choice of electrodes, the device may also be driven as an n-channel junction field-effect transistor. The gallium phosphide BJT is observed to have a common-emitter current gain peaking in the range of 6 to 10 (for temperatures from 20/sup 0/C to 400/sup 0/C) and a room-temperature, punchthrough-limited, collector-emitter breakdown voltage of approximately -6V. Other parameters of interest include an f/sub/ = 400 KHz (at 20/sup 0/C) and a collector base leakage current = 200 ..mu..A (at 350/sup 0/C).

Zipperian, T.E.; Dawson, L.R.; Caffin, R.J.

1981-03-01

37

Plenary, 2008 IEEE-CSIC Symposium, October 12, 2008 THz Bipolar Transistor Circuits  

E-print Network

Plenary, 2008 IEEE-CSIC Symposium, October 12, 2008 THz Bipolar Transistor Circuits: Technical;Simple Device Physics: Fringing Capacitance + 5.1 WC functionvarying-slowlyC + 5.1 TL plate 4:1 reduce width 4:1, keep constant length increase current density 4:1 #12;Bi lBipolar T i

Rodwell, Mark J. W.

38

Small-signal and noise model extraction technique for heterojunction bipolar transistor at microwave frequencies  

Microsoft Academic Search

The increasing use of Heterojunction Bipolar Transistors (HBT's) in microwave analog circuits requires a valid description of these devices by means of an equivalent circuit including noise sources in an extended bias and frequency range. This paper describes a technique to extract the elements of the equivalent circuit from simultaneous noise and S-parameter measurements. Additionally, the conventional high frequency bipolar

J. P. Roux; L. Escotte; R. Plana; J. Graffeuil; S. L. Delage; H. Blanck

1995-01-01

39

Silicon-germanium base heterojunction bipolar transistors by molecular beam epitaxy  

Microsoft Academic Search

We report the first SiGe base heterojunction Bipolar Transistors (HBT) The devices were fabricated using Molecular Beam Epitaxy (MBE), low temperature processing and different germanium contents. The transistors demonstrate current gain and show the expected increase in collector current as a result of reduced bandgap due to Ge incorporation in the base. A 6 times increase in collector current was

S. S. Iyer; G. L. Patton; S. S. Delage; S. Tiwari; J. M. C. Stork

1987-01-01

40

An analytic method for calculating current sharing in emitter-coupled bipolar transistors  

Microsoft Academic Search

This paper describes an analytic method for calculating current sharing in emitter coupled bipolar transistors. We use a simplified Ebers-Moll transistor model to approximate current sharing by first ignoring the terminal resistances. We then derive an analytic equation to compensate the collector currents in order to include the effect of terminal resistances. The model is accurate for a wide range

E. J. Brauer; S. M. Kang

1993-01-01

41

GaAs transistors formed by Be or Mg ion implantation  

NASA Technical Reports Server (NTRS)

N-p-n transistor structures have been formed in GaAs by implanting n-type substrates with Be ions to form base regions and then implanting them with 20-keV Si ions to form emitters. P-type layers have been produced in GaAs by implantation of either Mg or Be ions, with substrate at room temperature, followed by annealing at higher temperatures.

Hunsperger, R. G.; Marsh, O. J.

1974-01-01

42

InGaP/InGaAsN/GaAs NpN double heterojunction bipolar transistor  

SciTech Connect

The authors have demonstrated a functional NpN double heterojunction bipolar transistor (DHBT) using InGaAsN for base layer. The InGaP/In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01}/GaAs DHBT has a low V{sub ON} of 0.81 V, which is 0.13 V lower than in a InGaP/GaAs HBT. The lower V{sub ON} is attributed to the smaller bandgap (E{sub g}=1.20eV) of MOCVD grown In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01} base layer. GaAs is used for the collector; thus the BV{sub CEO} is 10 V, consistent with the BV{sub CEO} of InGaP/GaAs Hbts of comparable collector thickness and doping level. To alleviate the current blocking phenomenon caused by the larger {triangle}E{sub C} between InGaAsN and GaAs, a graded InGaAs layer with {delta}-doping is inserted at the base-collector junction. The improved device has a peak current gain of 7 with ideal IV characteristics.

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

2000-01-10

43

Graded-SiGe-base, poly-emitter heterojunction bipolar transistors  

Microsoft Academic Search

Si\\/Si1-xGex heterojunction bipolar transistors (HBTs) fabricated using a low-temperature epitaxial technique to form the SiGe graded-bandgap base layer are discussed. These devices were fabricated on patterned substrates and subjected to annealing cycles used in advanced bipolar processing. These devices, which have base widths under 75 mm, were found to have excellent junction qualities. Due to the small bandgap of SiGe,

G. L. Patton; D. L. Harame; J. M. C. Stork; B. S. Meyerson; G. J. Scilla; E. Ganin

1989-01-01

44

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

Microsoft Academic Search

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&T's CBIC-U2, 4 GHz f? complementary bipolar technology. Each channel contains the following functions: low-noise preamplification, pulse shaping and threshold discrimination.

I. Kipnis; H. Spieler; T. Collins

1994-01-01

45

Current gain rolloff in graded-base SiGe heterojunction bipolar transistors  

SciTech Connect

The authors report the experimental observation of a novel effect in SiGe heterojunction bipolar transistors (HBT's) with graded bases which results in a significant emitter-base bias dependence of the current gain. The nonideal collector current is caused by the interaction of the bias dependence of the emitter-base space-charge region width and the exponential dependence of the collector current on the germanium concentration at the edge of the space-charge region. The resulting current gain rolloff must be taken into account for accurate modeling of bipolar transistors with bandgap grading in the base.

Crabbe, E.F.; Cressler, J.D.; Patton, G.L.; Stork, J.M.C.; Comfort, J.H.; Sun, J.Y.C. (Thomas J. Watson Research Center, Yorktown Heights, NY (United States))

1993-04-01

46

A 40 GHz fT Si bipolar transistor LSI technology  

Microsoft Academic Search

A high-speed Si bipolar transistor with fT (cutoff frequency) of 40 GHz using advanced BSA (BSG self-aligned) technology is described. The advanced BSA technology is characterized by graded profiled collector, buried emitter electrode structure, and 0.8-?m design rule. The advanced BSA technology for further improving the fT performance of the sub-100-nm-deep base transistor has been developed by adding these three

M. Sugiyama; H. Takemura; C. Ogawa; T. Tashiro; T. Morikawa; M. Nakamae

1989-01-01

47

A single electron bipolar avalanche transistor implemented in 90 nm CMOS  

NASA Astrophysics Data System (ADS)

A Single Electron Bipolar Avalanche Transistor (SEBAT) with attoampere sensitivity and ?10 Hz off-count rate is successfully integrated into 90 nm CMOS. The reported SEBAT has 120 dB (10 Hz-10 MHz) dynamic range corresponding to 0-0.35 VBE, and an IE ?10-18-10-12 A. Single-transistor ADC operation of the SEBAT is demonstrated by AC-coupling signals into the base.

Webster, Eric A. G.; Richardson, Justin A.; Grant, Lindsay A.; Henderson, Robert K.

2012-10-01

48

High Current Gain In0.49Ga0.51P/GaAs Heterojunction Bipolar Transistors with Double Spacers Grown by Gas Source Molecular Beam Epitaxy  

NASA Astrophysics Data System (ADS)

This paper reports the improved performance of the lattice-matched N-p+-n In0.49Ga0.51P/GaAs heterojunction bipolar transistors(HBTs) with undoped spacers grown by the gas source molecular beam epitaxy. A 600 Å GaAs base doped with beryllium at 3×1019 cm-3 and a 1000 Å In0.49Ga0.51P emitter doped with silicon at 3×1017 cm-3 have been grown. On both sides of the base, the 50 Å undoped GaAs spacers were grown. Devices with emitter area of 100 × 100 ?m2 were fabricated by using selective wet chemical etching technique. The measured results of HBTs reveal good junction characteristics, and the common-emitter current gain reaches 320 at the collector current density of 280 A/cm2.

Chen, Xiao-Jie; Chen, Jian-Xin; Chen, Yi-Qiao; Peng, Peng; Yang, Quan-Kui; Li, Ai-Zhen

2000-12-01

49

SiGe-base heterojunction bipolar transistors: physics and design issues  

Microsoft Academic Search

It has been shown that SiGe technology has the capability to extend the performance of Si bipolar transistors at both high and low current levels. The ability to tailor the bandgap, independently of the doping profile design, provides considerable flexibility for optimizing cutoff frequency, intrinsic base resistance, and junction capacitances for a given application. It is concluded that, when combined

G. L. Patton; J. M. C. Stork; J. H. Comfort; E. F. Crabbe; B. S. Meyerson; D. L. Harame; J. Y.-C. Sun

1990-01-01

50

A breakdown model for the bipolar transistor to be used with circuit simulators  

SciTech Connect

A breakdown model for the output characteristics of the bipolar transistor (bjt) has been developed. The behavioral modeling capability of PSPICE, a popular SPICE program (with Emphasis on Integrated circuits) was used to implement the macromodel. The model predicts bjt output characteristics under breakdown conditions. Experimental data was obtained to verify the macromodel. Good agreement exits between the measured and the simulated results.

Keshavarz, A.A. [Alliance Technologies, Inc., Albuquerque, NM (United States); Raney, C.W.; Campbell, D.C. [Sandia National Labs., Albuquerque, NM (United States)

1993-08-01

51

Evaluation of the Radiation Tolerance of SiGe Heterojunction Bipolar Transistors Under  

E-print Network

Evaluation of the Radiation Tolerance of SiGe Heterojunction Bipolar Transistors Under 24GeV Proton Collider (LHC) upgrade), we evaluated the radiation hardness of a candidate technology for the front stages: before and after irradiation with 24 GeV protons up to fluences of 1016 p/cm2 , and after

California at Santa Cruz, University of

52

Silicon bipolar transistor: a viable candidate for high speed applications at liquid nitrogen temperature  

NASA Astrophysics Data System (ADS)

Despite its inherent speed advantage over CMOS technologies under loaded conditions, the silicon bipolar transistor historically has been dismissed as a viable candidate for digital applications in the 77 K environment. The principal reason for this is the well documented degradation in the device current gain at low temperatures. It is demonstrated in this paper that this conclusion is no longer valid with respect to state-of-the-art devices. The transistors used in this investigation have sufficient current gain at 77 K for most digital applications without intentional profile modification. Emitter coupled logic (ECL) circuits switch at < 100 ps speeds at 77 K, and reduced logic-swing operation offers the benefits of an attractive power-delay product. This paper examines the physics, design and performance issues associated with the low temperature operation of silicon bipolar transistors, and discusses the potential advantages of such devices for high speed applications in future low temperature computer systems.

Cressler, John D.

1990-12-01

53

Fabrication of sub-m bipolar transistor structures by scanning probe Shachar Richter, David Cahen,a)  

E-print Network

Fabrication of sub- m bipolar transistor structures by scanning probe microscopy Shachar Richter by a conducting atomic force microscope tip. The structures are characterized by nm scale scanning spreading

Manassen, Yishay

54

Demonstration of npn InAs bipolar transistors with inverted base doping  

SciTech Connect

The authors demonstrate np{sup +}n InAs bipolar transistors that operate under room temperature and cryogenic conditions. InAs transistors on an InP substrate were characterized as a function of temperature and exhibited good room temperature and low temperature common-emitter characteristics. Although the base doping density exceeded the emitter doping density by a factor of 20, current gains of 30 were achieved at room temperature. Junction leakage currents and contact resistance were identified as problems to address.

Dodd, P.E.; Lovejoy, M.L. [Sandia National Labs., Albuquerque, NM (United States)] [Sandia National Labs., Albuquerque, NM (United States); Lundstrom, M.S.; Melloch, M.R.; Woodall, J.M. [Purdue Univ., West Lafayette, IN (United States)] [Purdue Univ., West Lafayette, IN (United States); Pettit, D. [IBM, Yorktown Heights, NY (United States). T.J. Watson Research Center] [IBM, Yorktown Heights, NY (United States). T.J. Watson Research Center

1996-04-01

55

Bipolar transistor modeling of avalanche generation for computer circuit simulation  

Microsoft Academic Search

An avalanche generation model is developed and incorporated into computer circuit analysis programs SLIC and NICAP. A modified form of Miller's empirical expression for generation is found to agree well with measured data for Western Electric and commercial n-p-n transistors. Measurement techniques and parameter determination for the three model coefficients are discussed. Equation constraints appropriate for computer implementation are presented.

R. W. Dutton

1975-01-01

56

Implantation-Free 4H-SiC Bipolar Junction Transistors With Double Base Epilayers  

Microsoft Academic Search

This letter reports the first 4H-SiC power bipolar junction transistor (BJT) with double base epilayers which is completely free of ion implantation and hence of implantation-induced crystal damages and high-temperature activation annealing-induced surface roughness. Based on this novel design and implantation-free process, a 4H-SiC BJT was fabricated to reach an open base collector-to-emitter blocking voltage of over 1300 V, with

Jianhui Zhang; Xueqing Li; Petre Alexandrov; J. H. Zhao

2008-01-01

57

Application of insulated gate bipolar transistor to zero-current switching converters  

Microsoft Academic Search

The problems associated with insulated-gate bipolar transistor (IGBT) devices in PWM converters, such as turn-off current tailing and turn-off latching, are largely avoided in zero-current switching resonant converters. Phenomena induced by dv\\/dt, such as the power losses and latching, are identified as the predominant problems in using IGBT devices for very-high-frequency resonant operations. The discussion and the verification of the

R. Rangan; DAN Y. CHEN; Jian Yang; JOHN LEE

1989-01-01

58

An improved understanding for the transient operation of the power insulated gate bipolar transistor (IGBT)  

Microsoft Academic Search

It is shown that a nonquasi-static analysis must be used to describe the transient current and voltage waveforms of the insulated gate bipolar transistor. The nonquasi-static analysis is necessary because the transport of electrons and holes are coupled for the low-gain, high-level injection conditions, and the quasi-neutral base width changes faster than the base transit speed for typical load circuit

1990-01-01

59

An investigation of the drive circuit requirements for the power insulated gate bipolar transistor (IGBT)  

Microsoft Academic Search

The drive circuit requirements of the insulated gate bipolar transistor (IGBT) are explained with the aid of an analytical model. It is shown that nonquasi-static effects limit the influence of the drive circuit on the time rate-of-change of anode voltage. Model results are compared with measured turn-on and turn-off waveforms for different drive, load, and feedback circuits, and for different

1991-01-01

60

Vertical profile optimization of very high frequency epitaxial Si and SiGe-base bipolar transistors  

Microsoft Academic Search

Bipolar transistors with phosphorus-doped emitters and sub-50 nm epitaxial bases have been fabricated in a low thermal-cycle process to explore the trade-offs between cutoff frequency, breakdown voltage and Early voltage. Record peak fTs of 73 GHz for a Si BJT and 113 GHz for a SiGe HBT with respective ?VA products of 630 and 48,400 V were obtained for intrinsic

E. F. Crabbe; B. S. Meyerson; J. M. C. Stork; D. L. Harame

1993-01-01

61

75GHz fT SiGe-base heterojunction bipolar transistors  

Microsoft Academic Search

The fabrication of silicon heterojunction bipolar transistors which have a record unity-current-gain cutoff frequency (fT) of 75 GHz for a collector-base bias of 1 V, an intrinsic base sheet resistance (Rbi) of 17 k?\\/□, and an emitter width of 0.9 ?m is discussed. This performance level, which represents an increase by almost a factor of 2 in the speed of

GARY L. PATTON; JAMES H. COMFORT; BERNARD S. MEYERSON; E. F. Crabbe; G. J. Scilla; E. de Fresart; J. M. C. Stork; J. Y.-C. Sun; D. L. Harame; J. N. Burghartz

1990-01-01

62

High power operation of Pnp AlGaN\\/GaN heterojunction bipolar transistors  

Microsoft Academic Search

We fabricated a Pnp AlGaN\\/GaN heterojunction bipolar transistor and investigated its common - emitter current - voltage characteristics at room temperature. The device structures were grown by metalorganic vapor phase epitaxy on the sapphire substrates. The buffer layer was a newly developed Al2O3\\/AlN\\/AlON\\/Al2O3, resulting in the dislocation density of 6 × 108 cm-2 in MOVPE-grown GaN layer. This relatively low

K. Kumakura; Y. Yamauchi; T. Makimoto

2005-01-01

63

Dose-rate effects on radiation-induced bipolar junction transistor gain degradation  

SciTech Connect

Analysis of radiation damage in modern [ital NPN] bipolar transistors at various dose rates is performed with a recently introduced charge separation method and PISCES simulations. The charge separation method is verified with measurements on metal-oxide-semiconductor capacitors. Gain degradation is more pronounced at lower dose rates. The charge separation technique reveals that depletion-region spreading and effective recombination velocity are both greater for devices irradiated at lower dose rates.

Wei, A.; Kosier, S.L.; Schrimpf, R.D. (Department of Electrical and Computer Engineering, University of Arizona, Tucson, Arizona 85721 (United States)); Fleetwood, D.M. (Sandia National Laboratories, 1515 Eubank SE, Albuquerque, New Mexico 87123 (United States)); Combs, W.E. (Naval Surface Warfare Center, Building 2087, Code 6054, Crane, Indiana 47522 (United States))

1994-10-10

64

Portable urea biosensor based on the extended base bipolar junction transistor  

Microsoft Academic Search

In this study, an extended base bipolar junction transistor (EBBJT) was proposed to fabricate disposable urea biosensor. The detection of the urea is based on the variation of pH value. The gels, fabricated by the poly vinyl alcohol with pendent styrylpyridinium groups, were used to immobilize the urease. The SnO2\\/ITO glass, fabricated by sputtering SnO2 on the conductive ITO glass,

Chung-Yuan Chen; Hsiu-Li Shieh; Tai-Ping Sun

2010-01-01

65

Unified planar process for fabricating heterojunction bipolar transistors and buried-heterostructure lasers utilizing impurity-induced disordering  

NASA Astrophysics Data System (ADS)

We describe results on a novel geometry of heterojunction bipolar transistor that has been realized by impurity-induced disordering. This structure is fabricated by a method that is compatible with techniques for the fabrication of low threshold current buried-heterostructure lasers. We have demonstrated this compatibility by fabricating a hybrid laser/transistor structure that operates as a laser with a threshold current of 6 mA at room temperature, and as a transistor with a current gain of 5.

Thornton, R. L.; Mosby, W. J.; Chung, H. F.

1988-12-01

66

Tunneling-triggered bipolar action in junctionless tunnel field-effect transistor  

NASA Astrophysics Data System (ADS)

We analyse a novel hybrid semiconductor field-effect transistor (FET), known as the junctionless tunnel FET (JL-TFET). We show that a parasitic bipolar transistor action, which is highly undesirable in conventional metal/oxide/semiconductor FETs and junctionless transistors, is the mechanism that activates the JL-TFET ON state. It is found that the sub-threshold slope (SS) in the JL-TFET is strongly dependent on the silicon thickness and a sub-60 mV/decade SS is observed for a thin silicon body only. We further study the JL-TFET design parameters as regards the effects of the control gate workfunction, P-gate workfunction, and isolation region on the JL-TFET characteristics.

Gundapaneni, Suresh; Goswami, Aranya; Badami, Oves; Cuduvally, Ramya; Konar, Aniruddha; Bajaj, Mohit; Murali, Kota V. R. M.

2014-12-01

67

A scalable high-frequency noise model for bipolar transistors with application to optimal transistor sizing for low-noise amplifier design  

Microsoft Academic Search

Fully scalable, analytical HF noise parameter equations for bipolar transistors are presented and experimentally tested on high-speed Si and SiGe technologies. A technique for extracting the complete set of transistor noise parameters from Y parameter measurements only is developed and verified. Finally, the noise equations are coupled with scalable variants of the HICUM and SPICE-Gummel-Poon models and are employed in

Sorin P. Voinigescu; Michael C. Maliepaard; Jonathan L. Showell; Greg E. Babcock; David Marchesan; Michael Schroter; Peter Schvan; David L. Harame

1997-01-01

68

Bipolar Transistor with a Buried Layer Formed by High-Energy Ion Implantation for Subhalf-Micron Bipolar-Complementary Metal Oxide Semiconductor LSIs  

Microsoft Academic Search

We investigated a bipolar transistor with a buried layer formed by high-energy ion implantation without the epitaxitial silicon layer growth. We focused mainly on the reduction of junction leakage current related to implantation damages, which could be achieved by rapid thermal annealing. Consequently, the maximum current gain of 155 and the cutoff frequency of 17.3 GHz were achieved with BV

Takashi Kuroi; Youji Kawasaki; Yoshiyuki Ishigaki; Yasushi Kinoshita; Masahide Inuishi; Katsuhiro Tsukamoto; Natsuro Tsubouchi

1994-01-01

69

GSMBE grown In 0.49Ga 0.51P/GaAs heterojunction bipolar transistors with heavily beryllium doped base and undoped Spacer  

NASA Astrophysics Data System (ADS)

Lattice-matched N-p +-n In 0.49Ga 0.51P/GaAs heterojunction bipolar transistors (HBT's) with heavily beryllium doped base and undoped spacers were grown by gas source molecular beam epitaxy (GSMBE). The epitaxial structure consists of, from the bottom to the top, a 5000 Å n +-GaAs sub-collector with Si doping level of 3×10 18 cm -3, a 7000 Å n-GaAs collector doped at concentration of 3×10 16 cm -3, a 60 nm p +-GaAs base with Be doping level up to 3×10 19 cm -3 inserted between two undoped GaAs spacers, a 100 nm N-In 0.49Ga 0.51P emitter doped at 3×10 17 cm -3. The structure was completed with a 150 nm n +-GaAs cap layer with Si doping level of 3×10 18 cm -3. Devices with emitter area of 100×100 ?m were fabricated on the grown wafer by using selective wet chemical etching technique and photolithographic process. AuGeNi/Au was used for the emitter and collector contacts, and Cr/Au was used for the base contact. The turn-on voltages of p +-GaAs/N-In 0.49Ga 0.51P heterojunction and p +-GaAs/n-GaAs junction are 1.0 and 0.65 V. The reverse breakdown voltages of the B-E and B-C junctions are 10 and 12 V. The common-emitter current-voltage characteristics show that the maximum current gain reaches 320 at the collector current of 90 mA.

Chen, X. J.; Li, A. Z.; Chen, J. X.; Chen, Y. Q.; Yang, Q. K.

2001-07-01

70

Modeling Si/Si 1-xGe x heterojunction bipolar transistors  

NASA Astrophysics Data System (ADS)

Modeling Si/Si 1-xGe x/Si heterojunction bipolar transistors (HBTs) has been examined. The model equations account for valence- and conduction-band discontinuities, heavy doping effects and high collector current effects. Bias-dependent emitter resistance and heterojunction capacitances are also included. Comparison between the model prediction and the experimental data is used to demonstrate the model utility and accuracy. Good agreement between the model prediction and measurement has been obtained. The model is useful for predicting the gate delay of emitter-coupled logic at different temperatures.

Yuan, J. S.

1992-07-01

71

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

SciTech Connect

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.

Campbell, Phillip Montgomery; Wix, Steven D.

2013-05-01

72

Large-scale transient sensitivity analysis of a radiation damaged bipolar junction transistor.  

SciTech Connect

Automatic differentiation (AD) is useful in transient sensitivity analysis of a computational simulation of a bipolar junction transistor subject to radiation damage. We used forward-mode AD, implemented in a new Trilinos package called Sacado, to compute analytic derivatives for implicit time integration and forward sensitivity analysis. Sacado addresses element-based simulation codes written in C++ and works well with forward sensitivity analysis as implemented in the Trilinos time-integration package Rythmos. The forward sensitivity calculation is significantly more efficient and robust than finite differencing.

Hoekstra, Robert John; Gay, David M.; Bartlett, Roscoe Ainsworth; Phipps, Eric Todd

2007-11-01

73

73GHz self-aligned SiGe-base bipolar transistors with phosphorus-doped polysilicon emitters  

Microsoft Academic Search

The authors report a thermal-cycle emitter process using phosphorus for the fabrication of self-aligned SiGe-base heterojunction bipolar transistors. The low thermal cycle results in extremely, narrow basewidths and preservation of lightly doped spacers in both the emitter-base and base-collector junctions for improved breakdown. Transistors with 35-nm basewidths were obtained with low emitter-base reverse leakage and a peak cutoff frequency of

E. F. Crabbe; James H. Comfort; Wai Lee; John D. Cressler; Bernard S. Meyerson; Andrew C. Megdanis; Jack Y.-C. Sun; Johannes M. C. Stork

1992-01-01

74

Low-Capacitance Low-Voltage Transient Voltage Suppressor Using Diode-Activated SiGe Heterojunction Bipolar Transistor in SiGe Heterojunction Bipolar Transistor Bipolar Complementary Metal-Oxide-Semiconductor Process  

NASA Astrophysics Data System (ADS)

In this paper, a transient voltage suppressor using a diode-activated SiGe heterojunction bipolar transistor (HBT) is proposed. The capacitance, DC current-voltage (I-V) characteristics, and transmission line pulse (TLP) I-V characteristics of this combination device are investigated. An optimization guideline of the combination device is presented, verified by the corresponding simulation results, and a simple and effective method for achieving the target breakdown voltage is demonstrated. By combining the diode and SiGe HBT, the new structure exhibits both a low capacitance and a low breakdown voltage for protection against electrostatic discharge and electrical overstress in discrete or on-chip applications.

Dai, Sheng-Huei; Peng, Jeng-Jie; Chen, Chia-Cheng; Lin, Chrong-Jung; King, Ya-Chin

2009-04-01

75

Optical reduction of low frequency noise in cryogenic GaAs junction field effect transistor  

NASA Astrophysics Data System (ADS)

We demonstrated optical low frequency noise reduction in a n-type SONY GaAs junction field effect transistor (JFET) (gate width: 5?m; length: 1?m) operating at 4.2K. At 1Hz, a 6dB decrease and a 10dB increase in noise were observed when the JFET (band gap: 1.51eV) was illuminated by light with wavelengths of 1650 and 1550nm, respectively, for a drain voltage of 0.5V and drain current of 0.25?A. When the drain current was 0.5?A, 1650nm illumination increased the noise; moreover, hysteretic behavior in response to the illumination was also observed. These results show that deep level trapped charges apparently affect low frequency noise, which can be controlled by illumination using photons whose energies are below the band gap energy at cryogenic temperatures.

Fujiwara, M.; Nagata, H.; Matsuo, H.; Sasaki, M.

2008-07-01

76

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

SciTech Connect

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[sub 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 [mu]m pitch double-sided silicon strip detector. The chip measures 6.8 mm [times] 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 [phi] = 10[sup 14] protons/cm[sup 2] have been performed on the JC, demonstrating the radiation hardness of the complementary bipolar process.

Kipnis, I.; Spieler, H.; Collins, T. (Lawrence Berkeley Lab., CA (United States))

1994-08-01

77

SEMICONDUCTOR DEVICES: EMP injection damage effects of a bipolar transistor and its relationship between the injecting voltage and energy  

Microsoft Academic Search

The response of a bipolar transistor (BJT) under a square-wave electromagnetic pulse (EMP) with different injecting voltages is investigated. Adopting the curve fitting method, the relationship between the burnout time, the damage energy and the injecting voltage is obtained. Research shows that the damage energy is not a constant value, but changes with the injecting voltage level. By use of

Xi Xiaowen; Chai Changchun; Ren Xingrong; Yang Yintang; Zhang Bing; Hong Xiao

2010-01-01

78

Negative differential transconductance in silicon quantum well metal-oxide-semiconductor field effect/bipolar hybrid transistors  

NASA Astrophysics Data System (ADS)

Introducing explicit quantum transport into Si transistors in a manner amenable to industrial fabrication has proven challenging. Hybrid field-effect/bipolar Si transistors fabricated on an industrial 45 nm process line are shown to demonstrate explicit quantum transport signatures. These transistors incorporate a lateral ion implantation-defined quantum well (QW) whose potential depth is controlled by a gate voltage (VG). Quantum transport in the form of negative differential transconductance (NDTC) is observed to temperatures >200 K. The NDTC is tied to a non-monotonic dependence of bipolar current gain on VG that reduces drain-source current through the QW. These devices establish the feasibility of exploiting quantum transport to transform the performance horizons of Si devices fabricated in an industrially scalable manner.

Naquin, Clint; Lee, Mark; Edwards, Hal; Mathur, Guru; Chatterjee, Tathagata; Maggio, Ken

2014-11-01

79

High-performance K-band GaAs power field-effect transistors prepared by molecular beam epitaxy  

NASA Technical Reports Server (NTRS)

The maturity of the molecular beam epitaxy (MBE) technique for preparing device quality GaAs material for microwave applications is demonstrated by the excellent performance characteristics of K-band GaAs power field-effect transistors (FETs) fabricated on the MBE wafers. An output power of 710 mW with 4.5-dB gain and 17.7 percent power-added efficiency was achieved at 21 GHz with a 1.26-mm gate width pi-gate device. A similar device with a 0.56-mm gate width produced an output power of 320 mW with 5.0-dB gain and 26.6 percent power-added efficiency at 21 GHz. These are the best results yet reported to date for GaAs power FETs operated in the K-band frequency range.

Saunier, P.; Shih, H. D.

1983-01-01

80

Microwave damage susceptibility trend of a bipolar transistor as a function of frequency  

NASA Astrophysics Data System (ADS)

We conduct a theoretical study of the damage susceptibility trend of a typical bipolar transistor induced by a high-power microwave (HPM) as a function of frequency. The dependences of the burnout time and the damage power on the signal frequency are obtained. Studies of the internal damage process and the mechanism of the device are carried out from the variation analysis of the distribution of the electric field, current density, and temperature. The investigation shows that the burnout time linearly depends on the signal frequency. The current density and the electric field at the damage position decrease with increasing frequency. Meanwhile, the temperature elevation occurs in the area between the p-n junction and the n-n+ interface due to the increase of the electric field. Adopting the data analysis software, the relationship between the damage power and frequency is obtained. Moreover, the thickness of the substrate has a significant effect on the burnout time.

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

2012-09-01

81

Growth and Fabrication of GaN/AlGaN Heterojunction Bipolar Transistor  

SciTech Connect

A GaN/AlGaN heterojunction bipolar transistor structure with Mg doping in the base and Si Doping in the emitter and collector regions was grown by Metal Organic Chemical Vapor Deposition in c-axis Al(2)O(3). Secondary Ion Mass Spectrometry measurements showed no increase in the O concentration (2-3x10(18) cm(-3)) in the AlGaN emitter and fairly low levels of C (~4-5x10(17) cm (-3)) throughout the structure. Due to the non-ohmic behavior of the base contact at room temperature, the current gain of large area (~90 um diameter) devices was <3. Increasing the device operating temperature led to higher ionization fractions of the mg acceptors in the base, and current gains of ~10 were obtained at 300 degree C.

Abernathy, C.R.; Baca, A.G.; Cao, X.A.; Cho, H.; Dang, G.T.; Donovan, S.M.; Han, J.; Jung, K.B.; Pearton, S.J.; Ren, F.; Shul, R.J.; Willison, C.G.; Wilson, R.G.; Zhang, A.P.; Zhang, L

1999-03-16

82

InGaAs/InP heterojunction bipolar transistors for ultra-low power circuit applications  

SciTech Connect

For many modern day portable electronic applications, low power high speed devices have become very desirable. Very high values of f{sub T} and f{sub MAX} have been reported with InGaAs/InP heterojunction bipolar transistors (HBTs), but only under high bias and high current level operating conditions. An InGaAs/InP ultra-lowpower HBT with f{sub MAX} greater than 10 GHz operating at less than 20 {micro}A has been reported for the first time in this work. The results are obtained on a 2.5 x 5 {micro}m{sup 2} device, corresponding to less than 150 A/cm{sup 2} of current density. These are the lowest current levels at which f{sub MAX} {ge} 10 GHz has been reported.

Chang, P.C.; Baca, A.G.; Hafich, M.J.; Ashby, C.I.

1998-08-01

83

On the low-temperature static and dynamic properties of high-performance silicon bipolar transistors  

NASA Astrophysics Data System (ADS)

In a study performed at 400 to 77 K, Si bipolar transistors were found to have near-ideal characteristics at low temperatures, with beta as high as 80 at 77 K. Detailed calculations indicate that the conventional theory of the temperature dependence of beta does not match the data. The discrepancy can be removed if it is assumed that a phenomenological thermal barrier to hole injection is present. Emitter-coupled logic (ECL) ring oscillators are functional at 85 K with no degradation in speed until about 165 K (compared to 358 K). Calculations using a delay figure of merit indicate that fT, Rb, and Cc are the delay components most affected by low-temperature operation. It is also found that successful ECL circuit operation at reduced logic swings is possible, provided emitter resistance is kept small, and can be used to enhance low-temperature power-delay performance. These data suggest that conventionally designed high-performance bipolar devices are suitable for the low-temperature environment.

Cressler, John D.; Tang, Denny D.; Jenkins, Keith A.; Li, Guann-Pyng; Yang, Edward S.

1989-08-01

84

Silicon germanium heterojunction bipolar technology: the next leap in silicon?  

Microsoft Academic Search

SiGe heterostructure bipolar transistor (HBT) technology will allow circuit designers to combine the performance historically associated with compound semiconductor technologies such as GaAs with the integration levels, yield, and cost associated with conventional Si processing. At present, unloaded SiGe ECL circuits switch at sub20ps speeds, transistors exhibit cutoff frequencies in excess of 100GHz, and integration levels high enough to realize

John D. Cressler; D. L. Harame; J. H. Comfort; Johannes M. C. Stork; Bernard S. Meyerson; Thomas E. Tice

1994-01-01

85

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

SciTech Connect

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 {Kappa}, 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/sup 19/ cm/sup -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 {Kappa}. 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/sup 19/ cm/sup -3/ while keeping the base thickness constant, the minimum delay at liquid nitrogen can approach the delay of optimized devices at room temperature.

Stork, J.M.C.; Harame, D.L.; Meyerson, B.S.; Nguyen, T.N. (International Business Machines Corp., Yorktown Heights, NY (USA). Thomas J. Watson Research Center)

1989-08-01

86

High-Performance Composite-Collector InP/InGaAs Heterojunction Bipolar Transistors  

NASA Astrophysics Data System (ADS)

This paper describes composite-collector InP/InGaAs heterojunction bipolar transistors that exhibit high current density and good breakdown behavior simultaneously. The collector consists of 150-nm InGaAs and 150-nm lightly n-type doped InP. Additionally, a 30-nm-thick InGaAsP layer is sandwiched between them to minimize the accumulation of transit carriers. The proposed structure makes use of the space charge in the collector to reduce the collector-current multiplication coefficient. At high current density, the space charge decreases the electric-field intensity in the narrow-band-gap InGaAs and moves the high-electric-field region into the wide-band-gap InP. The fabricated transistors exhibit flat collector I-V curves, high current density of over 4 mA/?m2, and reasonably small knee voltage. They also show a peak ft of over 200 GHz and a peak fmax of about 350 GHz at a current density of 2 mA/?m2. The ring oscillator IC based on the emitter-coupled-logic gate provides the gate propagation delay of 3.83 ps/stage.

Kurishima, Kenji; Ida, Minoru; Ishii, Kiyoshi; Watanabe, Noriyuki

2004-04-01

87

Simulation of neutron displacement damage in bipolar junction transistors using high-energy heavy ion beams.  

SciTech Connect

Electronic components such as bipolar junction transistors (BJTs) are damaged when they are exposed to radiation and, as a result, their performance can significantly degrade. In certain environments the radiation consists of short, high flux pulses of neutrons. Electronics components have traditionally been tested against short neutron pulses in pulsed nuclear reactors. These reactors are becoming less and less available; many of them were shut down permanently in the past few years. Therefore, new methods using radiation sources other than pulsed nuclear reactors needed to be developed. Neutrons affect semiconductors such as Si by causing atomic displacements of Si atoms. The recoiled Si atom creates a collision cascade which leads to displacements in Si. Since heavy ions create similar cascades in Si we can use them to create similar damage to what neutrons create. This LDRD successfully developed a new technique using easily available particle accelerators to provide an alternative to pulsed nuclear reactors to study the displacement damage and subsequent transient annealing that occurs in various transistor devices and potentially qualify them against radiation effects caused by pulsed neutrons.

Doyle, Barney Lee; Buller, Daniel L.; Hjalmarson, Harold Paul; Fleming, Robert M; Bielejec, Edward Salvador; Vizkelethy, Gyorgy

2006-12-01

88

Long-Term Reliability of High Speed SiGe/Si Heterojunction Bipolar Transistors  

NASA Technical Reports Server (NTRS)

Accelerated lifetime tests were performed on double-mesa structure Si/Si0.7Ge0.3/Si npn heterojunction bipolar transistors, grown by molecular beam epitaxy, in the temperature range of 175C-275C. Both single- and multiple finger transistors were tested. The single-finger transistors (with 5x20 micron sq m emitter area) have DC current gains approximately 40-50 and f(sub T) and f(sub MAX) of up to 22 GHz and 25 GHz, respectively. The multiple finger transistors (1.4 micron finger width, 9 emitter fingers with total emitter area of 403 micron sq m) have similar DC current gain but f(sub T) of 50 GHz. 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 REID 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 the devices at room temperature 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. SiGe/Si based amplifier circuits were also subjected to lifetime testing and we extrapolate MTTF is approximately 1.1_10(exp 6) hours at 125iC junction temperature from the circuit lifetime data.

Ponchak, George E. (Technical Monitor); Bhattacharya, Pallab

2003-01-01

89

Double heterojunction GaAs-GaAlAs bipolar transistors grown by MOCVD for emitter coupled logic circuits  

Microsoft Academic Search

Double heterojonction N-p-N GaAlAs-GaAs-GaAlAs bipolar transistors (DHBT's) have been developed using MOCVD growth. We have investigated the influence of growth conditions on the d.c. characteristics of DHBT's. Devices with 0.2 µm base thichness and p = 2.1018cm-3exihibited common emitter current gain, ?, of up to 5500. The recombination current has been reduced such asbeta simeq 1for current densites as low

C. Dubon; R. Azoulay; P. Desrousseaux; J. Dangla; A. M. Duchenois; M. Hountondji; D. Ankri

1983-01-01

90

A Double-Heterojunction Bipolar Transistor Having a Degenerately Doped Emitter and Backward-Diode Base Contact  

Microsoft Academic Search

A double-heterojunction bipolar transistor having a degenerately doped emitter layer is investigated. The base-emitter Esaki diode introduces very low input impedance in the OFF-state but does not degrade the current gain at high forward bias. The heavily doped emitter layer makes it possible to scale the emit- ter-layer thickness considerably. The heavily doped emitter layer also allows contacting the base

D. Cohen-Elias; S. Kraus; S. Cohen; A. Gavrilov; D. Ritter

2011-01-01

91

Microwave power performance of InP-based double heterojunction bipolar transistors for C- and X-band applications  

Microsoft Academic Search

We report on the microwave performance of InP-based double heterojunction bipolar transistors (DHBT) for X-band and C-band applications with power cells operating at an output power greater than 2 W. Our power performance characterization indicated a combination of high power density and high efficiency at both 4.5 and 9 GHz. At 4.5 GHz we measured over 2 W output power

M. Hafizi; P. A. Macdonald; T. Liu; D. B. Rensch; T. C. Cisco

1994-01-01

92

Cryogenic operation of third-generation, 200GHz peak-fT, silicon-germanium heterojunction bipolar transistors  

Microsoft Academic Search

We present a comprehensive investigation of the cryogenic performance of third-generation silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) technology. Measurements of the current-voltage (dc), small-signal ac, and broad-band noise characteristics of a 200-GHz SiGe HBT were made at 85 K, 120 K, 150 K, 200 K, and 300 K. These devices show excellent behavior down to 85 K, maintaining reasonable dc

Bhaskar Banerjee; Sunitha Venkataraman; Yuan Lu; Qingqing Liang; Chang-Ho Lee; Sebastien Nuttinck; Dekhyuon Heo; Y.-J. E. Chen; J. D. Cressler; J. Laskar; G. Freeman; D. C. Ahlgren

2005-01-01

93

Self-aligned GaAs p-channel enhancement mode MOS heterostructure field-effect transistor  

Microsoft Academic Search

Self-aligned GaAs enhancement mode MOS heterostructure field-effect transistors (MOS-HFET) have been successfully fabricated for the first time. The MOS devices employ a Ga2O3 gate oxide, an undoped Al0.75Ga0.25As spacer layer, and undoped In0.2Ga0.8As as channel layer. The p-channel devices with a gate length of 0.6 ?m exhibit a maximum DC transconductance gm of 51 mS\\/mm which is an improvement of

Matthias Passlack; Jonathan K. Abrokwah; Ravi Droopad; Zhiyi Yu; Corey Overgaard; Sang In Yi; M. Hale; J. Sexton; A. C. Kummel

2002-01-01

94

Heat removal from bipolar transistor by loop heat pipe with nickel and copper porous structures.  

PubMed

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 ?m and nickel powder with grain size of 10 and 25 ?m 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

Nemec, Patrik; Smitka, Martin; Malcho, Milan

2014-01-01

95

Growth and fabrication of GaN/AlGaN heterojunction bipolar transistor  

SciTech Connect

A GaN/AlGaN heterojunction bipolar transistor structure with Mg doping in the base and Si doping in the emitter and collector regions was grown by metalorganic chemical vapor deposition on {ital c}-axis Al{sub 2}O{sub 3}. Secondary ion mass spectrometry measurements showed no increase in the O concentration (2{endash}3{times}10{sup 18} cm{sup {minus}3}) in the AlGaN emitter and fairly low levels of C ({approximately}4{endash}5{times}10{sup 17} cm{sup {minus}3}) throughout the structure. Due to the nonohmic behavior of the base contact at room temperature, the current gain of large area ({approximately}90 {mu}m diameter) devices was {lt}3. Increasing the device operating temperature led to higher ionization fractions of the Mg acceptors in the base, and current gains of {approximately}10 were obtained at 300 {degree}C. {copyright} {ital 1999 American Institute of Physics.}

Han, J.; Baca, A.G.; Shul, R.J.; Willison, C.G.; Zhang, L. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Ren, F.; Zhang, A.P.; Dang, G.T. [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Donovan, S.M.; Cao, X.A.; Cho, H.; Jung, K.B.; Abernathy, C.R.; Pearton, S.J. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Wilson, R.G. [Consultant, Stevenson Ranch, California 91381 (United States)] [Consultant, Stevenson Ranch, California 91381 (United States)

1999-05-01

96

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

PubMed Central

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??m and nickel powder with grain size of 10 and 25??m 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

Smitka, Martin; Malcho, Milan

2014-01-01

97

Multi-level interconnects for heterojunction bipolar transistor integrated circuit technologies  

SciTech Connect

Heterojunction bipolar transistors (HBTs) are mesa structures which present difficult planarization problems in integrated circuit fabrication. The authors report a multilevel metal interconnect technology using Benzocyclobutene (BCB) to implement high-speed, low-power photoreceivers based on InGaAs/InP HBTs. Processes for patterning and dry etching BCB to achieve smooth via holes with sloped sidewalls are presented. Excellent planarization of 1.9 {micro}m mesa topographies on InGaAs/InP device structures is demonstrated using scanning electron microscopy (SEM). Additionally, SEM cross sections of both the multi-level metal interconnect via holes and the base emitter via holes required in the HBT IC process are presented. All via holes exhibit sloped sidewalls with slopes of 0.4 {micro}m/{micro}m to 2 {micro}m/{micro}m which are needed to realize a robust interconnect process. Specific contact resistances of the interconnects are found to be less than 6 {times} 10{sup {minus}8} {Omega}cm{sup 2}. Integrated circuits utilizing InGaAs/InP HBTs are fabricated to demonstrate the applicability and compatibility of the multi-level interconnect technology with integrated circuit processing.

Patrizi, G.A.; Lovejoy, M.L.; Schneider, R.P. Jr.; Hou, H.Q. [Sandia National Labs., Albuquerque, NM (United States); Enquist, P.M. [Research Triangle Inst., Research Triangle Park, NC (United States)

1995-12-31

98

63-75 GHz fT SiGe-base heterojunction bipolar technology  

Microsoft Academic Search

Experimental results for maximum cut-off frequency (fT) values of 75 and 52 GHz were achieved for SiGe-base and Si-base bipolar transistors with intrinsic base sheet resistances in the 10-17 k?\\/square range. These results extend the speed of silicon bipolar devices into a regime previously reserved to GaAs and other compound semiconductor technologies. Excellent junction characteristics were also obtained for devices

G. L. Patton; J. H. Comfort; B. S. Meyerson; E. F. Crabbe; G. J. Scilla; E. de Fresart; J. M. C. Stork; J. Y.-C. Sun; D. L. Harame; J. Burghartz

1990-01-01

99

Noise parameters of InP-based double heterojunction base-collector self-aligned bipolar transistors  

Microsoft Academic Search

The noise performances of a new base-collector self-aligned technology of double-heterojunction single-finger InGaAs-InP bipolar transistor are investigated at 300 K. Noise parameter variations are studied versus frequency in the 2-18 GHz range, versus collector current and emitter area. A low minimum noise figure Fmin=0.6 dB is demonstrated at 2 GHz with a 4.8-?m2 emitter. Variations of Fmin show a minimum

V. Danelon; F. Aniel; J. L. Benchimol; M. Riet; P. Crozat; G. Vernet; R. Adde

1999-01-01

100

Temperature-dependent characteristics of an emitter-ledge passivated InGaP/GaAs heterojunction bipolar transistor  

NASA Astrophysics Data System (ADS)

The temperature-dependent dc characteristics and noise performance of an interesting InGaP/GaAs heterojunction bipolar transistor (HBT) with emitter ledge passivation are demonstrated. Experimentally, due to the emitter ledge passivation, higher current gains and wider collector current over the measured temperature range (300-400 K) are observed as compared to a conventional device. In addition, the studied device exhibits lower base current ideality factors, better thermal stabilities on dc current gains, lower base surface recombination current densities and improved device reliability. Therefore, the studied device is suitable for low-power and high-temperature electronic applications.

Chen, Tzu-Pin; Fu, Ssu-I.; Tsai, Jung-Hui; Lour, Wen-Shiung; Guo, Der-Feng; Cheng, Shiou-Ying; Liu, Wen-Chau

2006-12-01

101

Highly sensitive, photon number resolving detectors mediated by phonons using $?$-doped GaAs transistors  

E-print Network

We report a photon number resolving detector using two-dimensional electron gas (2DEG) based transistors. When the photon pulses impinge on the absorption region, the generated phonons dissipate ballistically in the 2DEG toward the trench isolated nanowire transistors near the surface. The phonon-electron interaction induces a positive conductance in the transistors, resulting in a current increase. With this principle, we obtain an internal quantum efficiency for this type of detector of up to 85%.

Xiulai Xu; Hugh Baker; David A. Williams

2010-05-03

102

Integration of a double-polysilicon emitter-base self-aligned bipolar transistor into a 0.5-?m BiCMOS technology for fast 4Mb SRAM's  

Microsoft Academic Search

The single-polysilicon non-self-aligned bipolar transistor in a 0.5-?m BiCMOS technology has been converted into a double-polysilicon emitter-base self-aligned bipolar transistor with little increase in process complexity. Improved bipolar performance in the form of smaller base resistance and base-collector capacitance, larger knee current, higher peak cutoff frequency, and shorter ECL gate delay has been demonstrated. This technology will prove useful in

J. D. Hayden; J. D. Burnett; A. K. Perera; T. C. Mele; F. W. Walczyk; V. Kaushik; C. S. Lage; Y.-C. See

1993-01-01

103

Graded-base InGaN/GaN heterojunction bipolar light-emitting transistors B. F. Chu-Kung,a  

E-print Network

Graded-base InGaN/GaN heterojunction bipolar light-emitting transistors B. F. Chu-Kung,a M. Feng, G; published online 25 August 2006 The authors report radiative recombination from a graded-base InGaN/GaN microwave power has been obtained from GaN field-effect transistors, very few operational GaN-based HBTs

Asbeck, Peter M.

104

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

NASA Astrophysics Data System (ADS)

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 to provide consistently accurate values for base sheet resistance for both Si- and SiGe-base transistors over a wide range of temperatures. A model for plasma-induced bandgap narrowing suitable for implementation in a numerical simulator has been developed. The appropriate method of incorporating this model in a drift -diffusion solver is described. The importance of including this model for low temperature simulation is demonstrated. With these models in place, the enhanced simulator has been used for evaluating and designing the Si- and SiGe-base bipolar transistors. Silicon-germanium heterojunction bipolar transistors offer significant performance and cost advantages over conventional technologies in the production of integrated circuits for communications, computer and transportation applications. Their high frequency performance at low cost, will find widespread use in the currently exploding wireless communication market. However, the high performance SiGe-base transistors are prone to have a low common-emitter breakdown voltage. In this dissertation, a modification in the collector design is proposed for improving the breakdown voltage without sacrificing the high frequency performance. A comprehensive simulation study of p-n-p SiGe-base transistors has been performed. Different figures of merit such as drive current, current gain, cut -off frequency and Early voltage were compared between a graded germanium profile and an abrupt germanium profile. The differences in the performance level between the two profiles diminishes as the base width is scaled down.

Shaheed, M. Reaz

1995-01-01

105

GaAs quantum well laser and heterojunction bipolar transistor integration using molecular beam epitaxial regrowth  

E-print Network

continues, the perfor- mance level of integrated devices are approaching their hybrid counterparts. `-lo to equal hybrid integrations."3 The sec- ond method creates a distributed capacitance between the doped, using liquid phase epitaxy (LPE) re- growth. We used MBE regrowth which allows greater con- ~= trol over

106

Numerical Simulation on the Device Structure of GaAs Floated Electron Channel Field-Effect Transistor  

NASA Astrophysics Data System (ADS)

In order to characterize the performance and design the optimal structure of the GaAs floated electron channel field-effect transistor (FECFET), we have carried out two-dimensional numerical simulation with varying the values of the key structure parameters of the FECFET. In the simulation, the uniform distribution of surface state charges on triangular void wall and the electron saturation velocity as a function of gate length are taken into account. It is shown from the simulation that the GaAs FECFET has an effective channel length of about 0.5 µ m and the vertical distance between the top vertex of void and the Ohmic layer front affects the channel length. When the gate-length-dependent saturation velocity is considered, the simulated current-gain cut-off frequency of the FECFET is linearly proportional to the reciprocal of the metallized gate length. When the gate is misaligned toward the drain direction, the transconductance values of the FECFET more abruptly decrease than in the case of misalignment toward the source direction.

Lee, Yoon-Jong; Kim, Chang-Tae; Hong, Song-Cheol; Kwon, Young-Se; Yoon, Hee-Koo; Oh, Kye-Whan

1995-02-01

107

Radiation hardness test of preamplifier circuits composed of commercial bipolar transistors  

NASA Astrophysics Data System (ADS)

In general, radiation-hardened transistors are very expensive and it is sometimes not easy to acquire proper ones for application. In this study, we designed a front-end electronic circuit for high-rate neutron counters installed in a high-level ?-radiation hot cell. All the transistors adopted for this circuit are not radiation-hardened ones, i.e. commercial ones not specifically processed for a radiation resistance. The aim of our study was to seek more radiation-resistant transistors from among the commercial ones and to verify the radiation hardness of the circuit composed of these transistors. The circuit includes a preamplifier, a comparator, and a monostable multivibrator. To realize the radiation hardness of this circuit with commercial transistors, the transistors were categorized into two groups: general speed and high-speed transistors. After a 100 Mrad irradiation from a 60Co ?-ray source, the reduction of the current gain of the general speed transistors was over 80% and that of the high-speed transistors was below 68%. The signal-to-noise ( S/ N) ratio of the preamplifier output voltage was reduced by 66% for the former and by 36% for the latter.

Lee, Tae-hoon; Kim, Ho-dong

2007-08-01

108

Comparison of total dose effects on SiGe heterojunction bipolar transistors induced by different swift heavy ion irradiation  

NASA Astrophysics Data System (ADS)

The degradations in NPN silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) were fully studied in this work, by means of 25-MeV Si, 10-MeV Cl, 20-MeV Br, and 10-MeV Br ion irradiation, respectively. Electrical parameters such as the base current (IB), current gain (?), neutral base recombination (NBR), and Early voltage (VA) were investigated and used to evaluate the tolerance to heavy ion irradiation. Experimental results demonstrate that device degradations are indeed radiation-source-dependent, and the larger the ion nuclear energy loss is, the more the displacement damages are, and thereby the more serious the performance degradation is. The maximum degradation was observed in the transistors irradiated by 10-MeV Br. For 20-MeV and 10-MeV Br ion irradiation, an unexpected degradation in IC was observed and Early voltage decreased with increasing ion fluence, and NBR appeared to slow down at high ion fluence. The degradations in SiGe HBTs were mainly attributed to the displacement damages created by heavy ion irradiation in the transistors. The underlying physical mechanisms are analyzed and investigated in detail.

Sun, Ya-Bin; Fu, Jun; Xu, Jun; Wang, Yu-Dong; Zhou, Wei; Zhang, Wei; Cui, Jie; Li, Gao-Qing; Liu, Zhi-Hong

2014-11-01

109

Lateral carrier diffusion and current gain in terahertz InGaAs/InP double-heterojunction bipolar transistors  

SciTech Connect

The DC current gain in In{sub 0.53}Ga{sub 0.47}As/InP double-heterojunction bipolar transistors is computed based on a drift-diffusion model, and is compared with experimental data. Even in the absence of other scaling effects, lateral diffusion of electrons to the base Ohmic contacts causes a rapid reduction in DC current gain as the emitter junction width and emitter-base contact spacing are reduced. The simulation and experimental data are compared in order to examine the effect of carrier lateral diffusion on current gain. The impact on current gain due to device scaling and approaches to increase current gain are discussed.

Chiang, Han-Wei; Rode, Johann C.; Choudhary, Prateek; Rodwell, Mark J. W. [Department of Electrical and Computer Engineering, University of California, Santa Barbara, California 93106 (United States)

2014-01-21

110

Passivation of InP heterojunction bipolar transistors by strain controlled plasma assisted electron beam evaporated hafnium oxide  

NASA Astrophysics Data System (ADS)

We present structural, stress, and electrical properties of plasma assisted e-beam evaporated hafnium dioxide (HfO2) layers on n-type InP substrates. These layers have subsequently been used for surface passivation of InGaAs/InP heterostructure bipolar transistors either alone or in combination with plasma enhanced chemical vapor deposited SiO2 layers. The use of stacked HfO2/SiO2 results in better interface quality with InGaAs/InP heterostructures, as illustrated by smaller leakage current and improved breakdown voltage. These improvements can be attributed to the reduced defect density and charge trapping at the dielectric-semiconductor interface. The deposition at room temperature makes these films suitable for sensitive devices.

Driad, R.; Sah, R. E.; Schmidt, R.; Kirste, L.

2012-01-01

111

Physical modeling based on hydrodynamic simulation for the design of InGaAs/InP double heterojunction bipolar transistors  

NASA Astrophysics Data System (ADS)

A physical model for scaling and optimizing InGaAs/InP double heterojunction bipolar transistors (DHBTs) based on hydrodynamic simulation is developed. The model is based on the hydrodynamic equation, which can accurately describe non-equilibrium conditions such as quasi-ballistic transport in the thin base and the velocity overshoot effect in the depleted collector. In addition, the model accounts for several physical effects such as bandgap narrowing, variable effective mass, and doping-dependent mobility at high fields. Good agreement between the measured and simulated values of cutoff frequency, ft, and maximum oscillation frequency, fmax, are achieved for lateral and vertical device scalings. It is shown that the model in this paper is appropriate for downscaling and designing InGaAs/InP DHBTs.

Ge, Ji; Liu, Hong-Gang; Su, Yong-Bo; Cao, Yu-Xiong; Jin, Zhi

2012-05-01

112

SEMICONDUCTOR DEVICES: EMP injection damage effects of a bipolar transistor and its relationship between the injecting voltage and energy  

NASA Astrophysics Data System (ADS)

The response of a bipolar transistor (BJT) under a square-wave electromagnetic pulse (EMP) with different injecting voltages is investigated. Adopting the curve fitting method, the relationship between the burnout time, the damage energy and the injecting voltage is obtained. Research shows that the damage energy is not a constant value, but changes with the injecting voltage level. By use of the device simulator Medici, the internal behavior of the burned device is analyzed. Simulation results indicate that the variation of the damage energy with injecting voltage is caused by the distribution change of hot spot position under different injection levels. Therefore, the traditional way to evaluate the trade-off between the burnout time and the injecting voltage is not comprehensive due to the variation of the damage energy.

Xiaowen, Xi; Changchun, Chai; Xingrong, Ren; Yintang, Yang; Bing, Zhang; Xiao, Hong

2010-04-01

113

Influence of the external component on the damage of the bipolar transistor induced by the electromagnetic pulse  

NASA Astrophysics Data System (ADS)

A study on the influence of the external resistor and the external voltage source during the injection of the electromagnetic pulse (EMP) into the bipolar transistor (BJT) is carried out. Research shows that the increase of the external resistor Rb at base makes the burnout time of the device decrease slightly, the increase of the external voltage source Vbe at base can aid the damage of the device when the magnitude of the injecting voltage is relatively low and has little influence when the magnitude is sufficiently high causing the device appearing the PIN structure damage, and the increase of the external resistor Re can remarkably reduce the voltage drops added to the device and improve the durability of the device. In the final analysis, the effect of the external circuit component on the BJT damage is the influence on the condition which makes the device appear current-mode second breakdown.

Xiaowen, Xi; Changchun, Chai; Xingrong, Ren; Yintang, Yang; Zhenyang, Ma; Jing, Wang

2010-07-01

114

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

SciTech Connect

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.

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

115

Improved methods of forming monolithic integrated circuits having complementary bipolar transistors  

NASA Technical Reports Server (NTRS)

Two new processes form complementary transistors in monolithic semiconductor circuits, require fewer steps /infusions/ than previous methods, and eliminate such problems as nonuniform h sub FE distribution, low yield, and large device formation.

Bohannon, R. O., Jr.; Cashion, W. F.; Stehlin, R. A.

1971-01-01

116

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

PubMed

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 ?A/decade at base currents of -50, -30, and -10 ?A, 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. PMID:21835604

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

2011-10-15

117

InGaP\\/GaAs heterojunction bipolar transistor grown on a semi-insulating InGaP buffer layer  

Microsoft Academic Search

To improve electrical isolation and simplify the heterojunction bipolar transistor (HBT) fabrication process, a semi-insulating InGaP buffer layer has been employed in an InGaP\\/GaAs HBT. Data is presented that demonstrates this buffer layer serves as an excellent isolation material. In addition, high-frequency HBT's have been fabricated and characterized to show that the buffer layer does not degrade device performance

D. A. Ahmari; M. T. Fresina; Q. J. Hartmann; D. W. Barlage; M. Feng; G. E. Stillman

1997-01-01

118

Electron saturation velocity of GaInP deduced in a GaInP/GaAs/GaInP double heterojunction bipolar transistor  

NASA Astrophysics Data System (ADS)

GaInP/GaAs/GaInP double heterojunction bipolar transistors have been fabricated for the study of electron saturation velocity (vsat) in GaInP. The necessary composite design at the base-collector junction, which effectively reduces the conduction band spike and avoids the premature Kirk effect, enables us to use the Kirk effect to study vsat. The deduced electron saturation velocity in GaInP is ˜5×106 cm/sec.

Hsin, Yue-Ming; Hsu, Shih-Tzung; Fan, Chen-Chung

2000-09-01

119

InP\\/InGaAs\\/InP double heterojunction bipolar transistors with improved dc and microwave performance grown by solid source molecular beam-epitaxy  

Microsoft Academic Search

This paper describes the fabrication and characterization of the InP\\/InAs\\/InP double heterojunction bipolar transistors grown by solid-source molecular beam epitaxy (SSMBE). An improvement in current gain and microwave noise has been observed for the SSMBE-grown InP\\/InGaAs DHBTs. The HBT with a 50 nm, 2 X 19 cm-3 Be-doped base exhibits dc current gain as high as 350, which is about

Hong Wang; Geok I. Ng; Hai Qun Zheng; Kaladhar Radhakrishnan; Soon Fatt Yoon; Yongzhong Xiong; Lye H. Chua; Hongru Yang; Subrata Halder; Chee L. Tan

2000-01-01

120

Silicon-germanium base heterojunction bipolar transistors by molecular beam epitaxy  

Microsoft Academic Search

The devices were fabricated using molecular-beam epitaxy (MBE), low-temperature processing, and germanium concentrations of 0, 6%, and 12%. The transistors demonstrate current gain, and show the expected increase in collector current as a result of reduced bandgap due to Ge incorporation in the base. For a 1000-Å base device containing 12% Ge, a six-times increase in collector current was measured

GARY L. PATTON; SUBRAMANIAN S. IYER; SYLVAIN L. DELAGE; S. Tiwari; J. M. C. Stork

1988-01-01

121

New high voltage ESD protection devices based on bipolar transistors for automotive applications  

Microsoft Academic Search

A novel ESD protection based on thyristor-like coupled NPN and PNP transistors is presented. This protection is developed in a 0.25 ?m SmartMOS® technology targeting 10 to 65 Volts IO pins. TCAD simulations are leveraged to analyze the physical behavior and a comprehensive qualification for automotive applications is presented, including HBM, MM and gun robustness measurements, transient voltage overshoot characterization

Amaury Gendron; Chai Gill; Carol Zhan; Mike Kaneshiro; Bill Cowden; Changsoo Hong; Richard Ida; Dung Nguyen

2011-01-01

122

Effect of aspect ratio on forward voltage drop in trench insulated gate bipolar transistor  

NASA Astrophysics Data System (ADS)

An analytical model for the carrier density at the accumulation layer of TIGBT (Trench Insulated Gate Transistor) is presented in terms of the aspect ratio with the influence of the depth of the trench gate below the P base taken into account. Based on the model, analytic expressions for the potential drop on the drift region are derived using a linear dependence of the carrier density on the aspect ratio. The analytical results for the forward voltage drop show a good agreement with the numerical simulations using MEDICI.

Moon, Jin-Woo; Choi, Yearn-Ik; Chung, Sang-Koo

2005-05-01

123

A 65-kV insulated gate bipolar transistor switch applied in damped AC voltages partial discharge detection system  

NASA Astrophysics Data System (ADS)

Damped AC voltages detection system (DAC) is a productive way to detect the faults in power cables. To solve the problems of large volume, complicated structure and electromagnetic interference in existing switches, this paper developed a compact solid state switch based on electromagnetic trigger, which is suitable for DAC test system. Synchronous electromagnetic trigger of 32 Insulated Gate Bipolar Transistors (IGBTs) in series was realized by the topological structure of single line based on pulse width modulation control technology. In this way, external extension was easily achieved. Electromagnetic trigger and resistor-capacitor-diode snubber circuit were optimized to reduce the switch turn-on time and circular layout. Epoxy encapsulating was chosen to enhance the level of partial discharge initial voltage (PDIV). The combination of synchronous trigger and power supply is proposed to reduce the switch volume. Moreover, we have overcome the drawback of the electromagnetic interference and improved the detection sensitivity of DAC by using capacitor storage energy to maintain IGBT gate driving voltage. The experimental results demonstrated that the solid-state switch, with compact size, whose turn-on time was less than 400 ns and PDIV was more than 65 kV, was able to meet the actual demands of 35 kV DAC test system.

Jiang, J.; Ma, G. M.; Luo, D. P.; Li, C. R.; Li, Q. M.; Wang, W.

2014-02-01

124

A novel 4H-SiC lateral bipolar junction transistor structure with high voltage and high current gain  

NASA Astrophysics Data System (ADS)

In this paper, a novel structure of a 4H-SiC lateral bipolar junction transistor (LBJT) with a base field plate and double RESURF in the drift region is presented. Collector-base junction depletion extension in the base region is restricted by the base field plate. Thin base as well as low base doping of the LBJT therefore can be achieved under the condition of avalanche breakdown. Simulation results show that thin base of 0.32 ?m and base doping of 3 × 1017 cm-3 are obtained, and corresponding current gain is as high as 247 with avalanche breakdown voltage of 3309 V when the drift region length is 30 ?m. Besides, an investigation of a 4H-SiC vertical BJT (VBJT) with comparable breakdown voltage (3357 V) shows that the minimum base width of 0.25 ?m and base doping as high as 8 × 1017 cm-3 contribute to a maximum current gain of only 128.

Deng, Yong-Hui; Xie, Gang; Wang, Tao; Sheng, Kuang

2013-09-01

125

Fabrication of InAlAs/InGaAsSb/InGaAs double heterojunction bipolar transistors  

SciTech Connect

A trilevel resist system was employed to fabricate self-aligned, submicron emitter finger In0.52Al0.48As/ In0.42Ga0.58As0.77Sb0.23 / In0.53Ga0.47As double heterojunction bipolar transistors DHBTs. Selective wet-etchants were used to define the emitter fingers and to form an InGaAs guard-ring around the emitter fingers. Due to the low energy bandgap of the InGaAsSb base layer and type II base-collector junction, a low turn-on voltage of 0.38 V at 1 A/cm2 and a high dc current gain of 123.8 for a DHBT with a 0.658.65 m2 emitter area were obtained. A unity gain cutoff frequency fT of 260 GHz and a maximum oscillation frequency fmax of 485 GHz at JC =302 kA/cm2 were achieved.

Lo, C. F. [University of Florida; Ren, F. [University of Florida; Chang, C. Y. [University of Florida; Pearton, S. J. [University of Florida; Chen, Shu-han [National Central University, Taiwan; Chyi, Jen-inn [National Central University, Taiwan; Wang, Sheng-yu [National Central University, Taiwan; Kravchenko, Ivan I [ORNL

2011-01-01

126

Advances in bipolar VLSI  

NASA Astrophysics Data System (ADS)

Bipolar IC processes are reviewed, and the impact of BiCMOS technology on bipolar VLSI is discussed. The discussion covers standard emitter-coupled-logic (ECL) circuit configuration, on-chip line driving, output circuitry, series gating, ECL versus CML (current-mode logic), differential logic, noise margins, interconnect capacitance, bipolar VLSI transistor design and scaling, and processes for ECL VLSI.

Wilson, George R.

1990-11-01

127

Variable-angle spectroscopic ellipsometry of InAlP native oxide dielectric layers for GaAs metal-oxide-semiconductor field effect transistor applications  

NASA Astrophysics Data System (ADS)

Variable angle spectroscopic ellipsometry models and data analysis have been developed to accurately determine the thickness of indium aluminum phosphide (InAlP) native oxide films used for the gate oxide in GaAs-based metal-oxide-semiconductor field effect transistor devices. The optical constants of the InAlP oxide, as well as InAlP and indium aluminum phosphide (InGaP) lattice matched to GaAs, have been determined by ellipsometry measurements using a photon energy range of 1.45 to 5.45 eV. Using the optical constants of InAlP and InAlP oxide, an ellipsometry-based model has been developed to characterize the oxidation kinetics of a thick partially oxidized InAlP epitaxial film grown on GaAs. The data indicate a delay in the full oxidation of In relative to Al as InAlP is fully oxidized. Excellent agreement between the thickness values determined by transmission electron microscopy imaging and by ellipsometric modeling validates the optical constants obtained. The ellipsometry material parameter models have also been extended to accurately fit the thickness of <100 Å InAlP oxides grown directly upon a multi-layer heterostructure for use as a transistor gate oxide. The InAlP oxide thicknesses determined by ellipsometry agree with those determined by electron microscopy to within 4%.

Yuan, Wangqing; Hall, D. C.

2013-03-01

128

A microwave GaAs FET power module with GaAs matching circuits - The M-FET (matched field effect transistor)  

NASA Astrophysics Data System (ADS)

A design approach for configuring microwave amplifier modules with GaAs circuit substrates is described. GaAs FET chips are used as active elements, with the input and output matching and bias circuits mounted on the GaAs chips. Lumped, matching and hybrid elements can be employed with the M-FETs, which have vertical integration. The features of a 6 GHz-FET with a 1 dB bandwidth are employed to illustrate the M-FET design and performance. Losses are noted to be a minimum at 0.1 dB with a 250 micron thick substrate in order to retain low impedance circuit elements. An eight-step process is used to manufacture the matching circuits. Trial results with an experimental M-FET are reported, demonstrating a 6.3 W output and 9 dB gain at a 550 MHz band.

Magalhaes, F. M.; Beccone, J. P.; Irvin, J. C.; Perelli, S. J.; Schlosser, W. O.

1985-05-01

129

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

NASA Astrophysics Data System (ADS)

Thin epitaxial poly-Si-emitter n-p-n transistors with increasing base doping (BD) show the effects of bandgap narrowing (BGN), mobility changes, and carrier freezeout. At room temperature the low-injection collector current is proportional to the integrated base charge, independent of the impurity distribution. Below 150 K, however, minority injection is dominated by the peak BD because of the greater effectiveness of BGN. When the peak BD approaches 10 to the 19th/cu cm, the bandgap difference between emitter and base is small, and the current gain no longer monotonically decreases with temperature but shows a maximum as low as 180 K. Using the measured dc characteristics, circuit delay calculations are made to estimate the performance of an emitter-coupled logic ring oscillator. If BD can be raised to 10 to the 19th/cu cm while keeping the base thickness constant, the minimum delay at 77 K can approach the delay of optimized devices at room temperature.

Stork, Johannes M. C.; Harame, David L.; Meyerson, Bernard S.; Nguyen, Thao N.

1989-08-01

130

Pure valley- and spin-entangled states in a MoS2-based bipolar transistor  

NASA Astrophysics Data System (ADS)

In this study, we show that the local Andreev reflection not only can be tuned largely by the type of the normal metal electrode, it also is related to the electrostatic potential in the superconductor region in a MoS2-based n (p ) -type metal/superconductor junction. In a MoS2-based n -type metal/n (p ) -type superconductor/p -type metal (n Sp ) transistor, nonlocal pure valley- and spin-entangled current can be tuned by the length and local gate voltage of a superconductor region. In particular, switching the quasiparticle type in both structures results in a series of intriguing features. Such an effect is not attainable in a graphene-based junction where the electron-hole symmetry enables the symmetry results to be observed. Besides, we have shown that the crossed Andreev reflection exhibits a maximum around ? /2 instead of the exponential decay behavior in conventional superconductors and a maximum around ? in the graphene material. The proposed straightforward experimental design and pure valley- and spin-entangled state can pave the way for a wider use in the entanglement based on material group-VI dichalcogenides.

Bai, Chunxu; Zou, Yonglian; Lou, Wen-Kai; Chang, Kai

2014-11-01

131

Collector-up aluminum gallium arsenide/gallium arsenide heterojunction bipolar transistors using oxidized aluminum arsenide for current confinement  

NASA Astrophysics Data System (ADS)

The discovery in 1990 that the wet thermal oxidation of AlAs can create a stable native oxide has added a new constituent, AlAs-oxide, to the AlGaAs/GaAs materials system. Native oxides of high Al mole-fraction AlGaAs are being used to confine electrical and/or optical fields in many types of electronic and optoelectronic structures with very promising results. Among these devices are collector-up heterojunction bipolar transistors (HBTs). Collector-up HBTs offer a means to reduce base-collector capacitance relative to their emitter-up counterparts, and thus to improve device performance. A novel method for fabricating collector-up AlGaAs/GaAs HBTs where an AlAs layer is inserted into the emitter layer and is oxidized in water vapor at 450sp°C has been developed. The resulting AlAs-oxide serves as a current confining layer that constricts collector current flow to the intrinsic portion of the device. Compared to previous methods of fabricating these devices, the process of converting AlAs into an insulator requires only one growth, and does not suffer from implant damage in the base. Because the lateral oxidation of AlAs is a process that proceeds at rates of microns per minute, one of the major challenges facing its implementation is the ability to accurately control the oxidation rate over the wafer, and from one wafer to the next. In the course of work on the oxidation of AlAs, a method to lithographically form lateral oxidation stop layers has been achieved. This technique utilizes impurity induced layer disordering (IILD) in heavily Si-doped buried planes, combined with selective surface patterning and thermal annealing, to create a lateral variation in the Al mole-fraction of the layer to be oxidized.

Massengale, Alan Ross

1998-12-01

132

The physics of high-speed transistors  

Microsoft Academic Search

This book considers the physics of high-speed transistors operating at frequencies above 10 Ghz and whose switching time is shorter than 100 ps. The physical principles permitting the augmentation of transistor speed are elaborated with reference to traditional types of transistors (bipolar and FET), the advanced heterostructure and ballistic transistors, and new concepts such as quantum transistors. The high-speed transistors

Iuras K. Pozhela

1989-01-01

133

LOW LEAKAGE CURRENT METAMORPHIC InGaAs/InP DHBTs WITH f and fmax > 268 GHz ON A GaAs SUBSTRATE  

E-print Network

LOW LEAKAGE CURRENT METAMORPHIC InGaAs/InP DHBTs WITH f and fmax > 268 GHz ON A GaAs SUBSTRATE Z-893-8044 Abstract Metamorphic InP/In0.53Ga0.47/InP double heterojunction bipolar transistors (mHBT) were grown etch and increase device yield. The metamorphic buffer layer is InP--employed because of its high

Rodwell, Mark J. W.

134

Growth of SiGe heterojunction bipolar transistor using Si 2H 6 gas and Ge solid sources molecular beam epitaxy  

NASA Astrophysics Data System (ADS)

N-p-n Si/SiGe/Si heterostructure has been grown by a disilane (Si 2H 6) gas and Ge solid sources molecular beam epitaxy system using phosphine (PH 3) and diborane (B 2H 6) as n- and p-type in situ doping sources, respectively. X-ray diffraction (XRD) and secondary ion mass spectroscopy (SIMS) measurements show that the grown heterostructure has a good quality, the boron doping is confined to the SiGe base layer, and the Ge has a trapezoidal profile. Post-growth P implantation was performed to prepare a good ohmic contact to the emitter. Heterojunction bipolar transistor (HBT) has been fabricated using the grown heterostructure and a common-emitter current gain of 75 and a cut-off frequency of 20 GHz at 300 K have been obtained.

Gao, F.; Huang, D. D.; Li, J. P.; Kong, M. Y.; Sun, D. Z.; Li, J. M.; Zeng, Y. P.; Lin, L. Y.

2001-03-01

135

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

NASA Astrophysics Data System (ADS)

We describe a reliable technique to separate the different contributions to the apparent base resistance (RB = RBx + X RBi) of silicon germanium carbon (SiGe:C) heterojunction bipolar transistors (HBTs). The extrinsic base resistance (RBx) is quantified using small-signal measurements. The base-collector junction distribution factor (X) and the intrinsic base resistance (RBi) 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.

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

2014-09-01

136

Vertical electron transistor (VET) in GaAs with a heterojunction (AlGaAs-GaAs) cathode  

NASA Astrophysics Data System (ADS)

The successful fabrication of submicrometer channel length (0.75 micron) and gate length (0.15 micron) vertical electron transistors with AlGaAs cathodes is reported. Lack of electron velocity enhancement has been proposed to be due to high operating channel temperatures, and low temperature measurements were hindered by carrier freeze-out.

Mishra, U.; Maki, P. A.; Wendt, J. R.; Schaff, W.; Kohn, E.; Eastman, L. F.

1984-02-01

137

Bipolar transistor and diode failure to electrical transients-predictive failure modeling versus experimental damage testing. 1: Junction capacitance damage model  

NASA Astrophysics Data System (ADS)

For all the difficulties engendered in its use, semiconductor device damage data are an integral part of many programs of electromagnetic pulse vulnerability assessment and hardening. Experimental damage data, which are generated only as a result of dedicated efforts, can be expected to be available for only a minor fraction of all semiconductor devices. This limited supply has spurred efforts to develop predictive damage models, in order to bypass the tedious experimental requirements for generating damage data. The predictive ability of the best of these models, the junction capacitance damage model, is investigated in detail. Central to this study is a library of experimental damage data for 46 silicon device types, comprising bipolar transistors and diodes tested at the 10-, 1-, and 0.1-micro-sec. pulse durations. These are devices from the front ends of a number of Army systems and represent radio, field wire, and cable functions with operating ranges in the direct current (dc) to microwave region. Of the 46 experimental devices comprising 68 junction types (collector-to-base and emitter-to-base junctions treated as distinct for all transistors), sufficient published manufacturers' data were available for the damage modeling of 11 junctions. These were supplemented with measured parameters for 27 junction types.

Vrabel, M. J.

1981-06-01

138

Chemical and Electrochemical Nanofabrication Processes for Schottky In-Plane Gate GaAs Single and Coupled Quantum Wire Transistors  

NASA Astrophysics Data System (ADS)

Chemical and electrochemical nanofabrication processes used for fabricating GaAs-based single and coupled quantum wire transistors (QWTrs) utilizing Schottky in-plane gate (IPG) structures are described. IPG and metal dot formation processes using a wet chemical etching and an in situ electrochemical process were optimized for a novel nanodevice fabrication. Fabricated single and coupled QWTrs showed conductance quantization and oscillation characteristics at low temperatures, demonstrating the tight gate control capability.

Iwaya, Masanobu; Kasai, Seiya; Okada, Hiroshi; Nakamura, Jin; Hasegawa, Hideki

2000-07-01

139

Highly strained InGaAs layers on GaAs grown by molecular beam epitaxy for high electron mobility transistors  

NASA Astrophysics Data System (ADS)

We have grown highly strained In xGa 1- xAs layers on GaAs, by molecular beam epitaxy, showing excellent electrical and optical quality for high electron mobility transistors (HEMTs). Over a very narrow range of substrate temperature from 400 to 420°C, the mobility of 6 nm thick In 0.35Ga 0.65As channel HEMTs at room temperature exceeds 6200 cm 2/V · s. Furthermore, the In composition can be increased up to 0.42 without generating misfit dislocations. The peak energy and full width at half maximum of a 77 K photoluminescence spectrum from an In 0.42Ga 0.58As/GaAs (well width = 6 nm) strained single quantum well are as small as 1.082 eV and 9.8 meV, respectively. The highly strained In xGa 1- xAs channel HEMTs (0.3 ? x ? 0.4) show superior transconductance over conventional In 0.25Ga 0.75As channel HEMTs.

Kudo, Makoto; Mishima, Tomoyoshi; Washima, Mineo

1995-05-01

140

Characteristics of GaAs Schottky in-plane gate quantum wire transistors for switching of quantized conductance  

NASA Astrophysics Data System (ADS)

Basic transport and charge control characteristics of the Schottky in-plane gate (IPG) quantum wire transistor (QWTr) were investigated experimentally and theoretically as a possible key switching device in future high-density quantum integrated circuits. The fabricated QWTrs showed one-dimensional ballistic transport. From this, use of switching between zeroth and first conductance step was proposed for logic and memory application. Experimental and theoretical investigations were made on the threshold voltage and the steepness of the first quantized conductance step, and fairly good agreements were obtained between experiment and theory.

Okada, Hiroshi; Hasegawa, Hideki

1999-12-01

141

Effect of Ge Concentration on Static and Microwave Performances in GexSi1-x Heterojunction Bipolar Transistors under High-Level Injection  

NASA Astrophysics Data System (ADS)

We report the theoretical investigation of the effect of Ge concentration on both static and high-frequency performances in polycrystalline silicon emitter Ge xSi1- x heterojunction bipolar transistors (HBTs). The calculation is carried out up to 0.95 V, before the onset of the Kirk effect [C. T. Kirk: IEEE Trans. Electron Devices ED-9 (1962) 164]. From this model, we find that the current gain, transconductance, cutoff frequency, and maximum oscillation frequency increase with increasing Ge concentration. In addition, the base transit time and the switching delay time in the emitter-coupled logic circuit slightly decrease as Ge content increases. Furthermore, it shows that the high-level injection effect becomes more pronounced in the Ge xSi1- x HBT as Ge concentration increases. Compared with the conventional low-level injection model, the improved model provides much more accurate expressions for electrical characteristics of Ge xSi1- x HBTs operating under high-level injection.

Chyan, Yih-Feng; Sze, Simon; Chang, Chun-Yen; Reif, Rafael

1994-04-01

142

Fabrication and Characterization of Self-aligned InAlAs/InGaAsSb/InGaAs Double Heterojunction Bipolar Transistors  

SciTech Connect

A trilevel resist system was employed to fabricate self-aligned, submicron emitter finger In0.52Al0.48As/In0.42Ga0.58As0.77Sb0.23/ In0.53Ga0.47As double heterojunction bipolar transistors (DHBTs). Selective wet-etchants were used to define the emitter fingers and to form an InGaAs guard-ring around the emitter fingers. Due to the low energy bandgap of the InGaAsSb base layer and type II base-collector junction, a low turn-on voltage of 0.38 V at 1 A/cm2 and a high dc current gain of 123.8 for a DHBT with a 0.65 8.65 m2 emitter area were obtained. A unity gain cut-off frequency (fT) of 260 GHz and a maximum oscillation frequency (fmax) of 485 GHz at JC = 302 kA/cm2 were achieved.

Lo, C. F. [University of Florida; Chang, C. Y. [University of Florida; Chen, Shu-han [National Central University, Taiwan; Wang, Sheng-yu [National Central University, Taiwan; Chyi, Jen-inn [National Central University, Taiwan; Kravchenko, Ivan I [ORNL; Pearton, S. J. [University of Florida; Ren, F. [University of Florida

2011-01-01

143

Experiments and modeling of the photocurrent response of GaAs MESFETs  

NASA Astrophysics Data System (ADS)

1-micron technology GaAs MESFETs were exposed to a transient radiation environment at the Rensselaer Gaerttner linear accelerator laboratory and modeled by computer simulation using a modified version of the PISCES-IIB semiconductor device simulation code and the TRIGSPICE circuit simulation code. The MESFETs were tested in steady-state conditions, with short (20-ns) radiation pulses and with short pulses on devices that had received a prior dose of gamma, neutron, or neutron-plus-gamma irradiation. Parasitic bipolar action was observed in the short pulse testing in unexposed devices. Previously unreported transient failure was observed in the neutron preirradiated devices only. The threshold for this failure is consistent with the level of severity of prior irradiation. Steady-state photocurrent and the parasitic bipolar transistor are modeled and explained on the basis of physical mechanisms.

Howard, J. W.; Islam, N. E.; Ishaque, A. N.; Block, R. C.; Becker, M.

1990-12-01

144

Stability of carbon and beryllium-doped base GaAs/AlGaAs heterojunction bipolar transistors  

NASA Astrophysics Data System (ADS)

GaAs/AlGaAs heterojunction bipolar transitors (HBTs) utilizing highly Be-doped base layers display a rapid degradation of dc current gain and junction ideality factors during bias application at elevated temperature. For example, the gain of a 2×10 ?m2 device with a 4×1019 cm-3 Be-doped base layer operated at 200 °C with a collector current of 2.5×104 A cm-2 falls from 16 to 1.5 within 2 h. Both the base emitter and base collector junction ideality factors also rise rapidly during device operation, and this current-induced degradation is consistent with recombination-enhanced diffusion of Be interstitials producing graded junctions. By sharp contrast, devices with highly C-doped (p=7×1019 cm-3) base layers operated under the same conditions show no measurable degradation over much longer periods (12 h). This high degree of stability is most likely a result of the fact that C occupies the As sublattice, rather than the Ga sublattice as in the case of Be, and also has a higher solubility than Be. The effect of nearby implant isolated regions in promoting Be diffusion is also reported.

Ren, F.; Fullowan, T. R.; Lothian, J.; Wisk, P. W.; Abernathy, C. R.; Kopf, R. F.; Emerson, A. B.; Downey, S. W.; Pearton, S. J.

1991-12-01

145

Hardness assurance testing and radiation hardening by design techniques for silicon-germanium heterojunction bipolar transistors and digital logic circuits  

NASA Astrophysics Data System (ADS)

Hydrocarbon exploration, global navigation satellite systems, computed tomography, and aircraft avionics are just a few examples of applications that require system operation at an ambient temperature, pressure, or radiation level outside the range covered by military specifications. The electronics employed in these applications are known as "extreme environment electronics." On account of the increased cost resulting from both process modifications and the use of exotic substrate materials, only a handful of semiconductor foundries have specialized in the production of extreme environment electronics. Protection of these electronic systems in an extreme environment may be attained by encapsulating sensitive circuits in a controlled environment, which provides isolation from the hostile ambient, often at a significant cost and performance penalty. In a significant departure from this traditional approach, system designers have begun to use commercial off-the-shelf technology platforms with built in mitigation techniques for extreme environment applications. Such an approach simultaneously leverages the state of the art in technology performance with significant savings in project cost. Silicon-germanium is one such commercial technology platform that demonstrates potential for deployment into extreme environment applications as a result of its excellent performance at cryogenic temperatures, remarkable tolerance to radiation-induced degradation, and monolithic integration with silicon-based manufacturing. In this dissertation the radiation response of silicon-germanium technology is investigated, and novel transistor-level layout-based techniques are implemented to improve the radiation tolerance of HBT digital logic.

Sutton, Akil K.

146

Probing plasma-surface interactions with the transmission electron microscope or the Si-collector interface of the plasma bipolar junction transistor  

NASA Astrophysics Data System (ADS)

Two platforms developed to probe the plasma-solid interface are briefly reviewed here. A sensitive diagnostic of the interaction between a low-temperature plasma and a silicon surface is provided by the plasma bipolar junction transistor (PBJT) in which e--h+ (semiconductor) and e--ion (gas phase) plasmas are separated by a nanoscale potential barrier but coupled by a strong (>1 V µm-1) electric field. Electrical properties of the Si base-collector plasma interface are controlled by the bias applied to the PBJT emitter-base junction, as well as the morphology and electronic structure of the base surface facing the collector plasma. Recent experiments are described in which the Si(100) surface of the PBJT base is transformed into black Si, a nanostructured array comprising ˜3 × 109 nanocones. Each cone is ˜100 nm in height and has a radius of curvature at its tip of <1 nm. Altering the base surface so as to intentionally enhance field emission results in burst-mode operation of the PBJT in which the collector current oscillates as a result of the periodic contraction (or collapse) and revival of the plasma sheath. The observed oscillation frequencies (3.6-13 kHz) are consistent with the transit time of ions across the sheath. Integration of a microplasma device with a transmission electron microscope has also been realized recently (Tai et al 2013 Sci. Rep. 3 1325). This diagnostic tool allows plasma-surface interactions to be observed in real-time with a spatial resolution <100 nm. Although initial experiments concerned the growth of Au islands in a dc plasma, the extension of this probe to nanostructured and spatially modulated surfaces is proposed.

Houlahan, T. J., Jr.; Li, B.; Xu, Z.; Jiang, J.; Liu, G. L.; Ruzic, D. N.; Eden, J. G.

2013-11-01

147

Gallium arsenide-gallium nitride wafer fusion and the n-aluminum gallium arsenide/p-gallium arsenide/n-gallium nitride double heterojunction bipolar transistor  

NASA Astrophysics Data System (ADS)

This dissertation describes the n-AlGaAs/p-GaAs/n-GaN heterojunction bipolar transistor (HBT), the first transistor formed via wafer fusion. The fusion process was developed as a way to combine lattice-mismatched materials for high-performance electronic devices, not obtainable via conventional all-epitaxial formation methods. Despite the many challenges of wafer fusion, successful transistors were demonstrated and improved, via the optimization of material structure and fusion process conditions. Thus, this project demonstrated the integration of disparate device materials, chosen for their optimal electronic properties, unrestricted by the conventional (and very limiting) requirement of lattice-matching. By combining an AlGaAs-GaAs emitter-base with a GaN collector, the HBT benefited from the high breakdown voltage of GaN, and from the high emitter injection efficiency and low base transit time of AlGaAs-GaAs. Because the GaAs-GaN lattice mismatch precluded an all-epitaxial formation of the HBT, the GaAs-GaN heterostructure was formed via fusion. This project began with the development of a fusion process that formed mechanically robust and electrically active GaAs-GaN heterojunctions. During the correlation of device electrical performance with a systematic variation of fusion conditions over a wide range (500--750°C, 0.5--2hours), a mid-range fusion temperature was found to induce optimal HBT electrical performance. Transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS) were used to assess possible reasons for the variations observed in device electrical performance. Fusion process conditions were correlated with electrical (I-V), structural (TEM), and chemical (SIMS) analyses of the resulting heterojunctions, in order to investigate the trade-off between increased interfacial disorder (TEM) with low fusion temperature and increased diffusion (SIMS) with high fusion temperature. The best do device results (IC ˜ 2.9 kA/cm2 and beta ˜ 3.5, at VCE = 20V and IB = 10mA) were obtained with an HBT formed via fusion at 600°C for 1 hour, with an optimized base-collector design. This was quite an improvement, as compared to an HBT with a simpler base-collector structure, also fused at 600°C for 1 hour (IC ˜ 0.83 kA/cm2 and beta ˜ 0.89, at VCE = 20V and IB = 10mA). Fused AlGaAs-GaAs-GaAs HBTs were compared to fused AlGaAs-GaAs-GaN HBTs, demonstrating that the use of a wider bandgap collector (Eg,GaN > Eg,GaAs) did indeed improve HBT performance at high applied voltages, as desired for high-power applications.

Estrada, Sarah M.

148

Geometry Effect on SiGe Heterojunction Bipolar Transistor Unit Cell for 1 W High-Efficiency RF Power Amplifier Applications  

NASA Astrophysics Data System (ADS)

The effect of geometry on the RF power performance of silicon-germanium heterojunction bipolar transistor (SiGe HBT) unit cells is investigated using various emitter finger spacing (S). Two unit cells, namely, HBT-1 and HBT-2 with the same emitter area of 8× 0.6× 10 ?m3 but with different S values are thoroughly discussed. The S values of HBT-1 and an HBT-2 are 2 and 5 ?m, respectively. The obtained measurements, including DC characteristics and small- and large-signal performance characteristics of high-breakdown SiGe HBT unit cells, are presented. The HBT-1 in class-AB operations at 2.4 GHz achieves an output 1 dB compression point (OP1dB) of 16.0 dBm, a maximum output power of 17.4 dBm, and a peak-power added efficiency (PAE) of 59.1%. Under the same testing conditions, HBT-2 achieves an OP1dB of 19.6 dBm, a maximum output power of 20.6 dBm, and a PAE of 64.5%. HBT-2 yields significant improvements in all power performance parameters compared with HBT-1, such as 3.6 dB in an OP1dB, a maximum output power of 3.2 dB, a PAE of 5.4%, and an improvement in the power performance figure of merit (FOM) of approximately 50%, which is attributed to the fact that HBT-2 has a lower thermal effect than HBT-1. The thermal effect affects both DC and output power characteristics. A 1 W power device fabricated by combining eight HBT-2 unit cells achieves a power gain of 14.5 dB and a maximum PAE (\\mathit{PAE}max) of 75% in a class-AB operation at 2.4 GHz. The power density is calculated to be up to 2.6 mW/?m2. These results demonstrate that SiGe HBT technology has great potential for high-power amplifier applications.

Chiou, Hwann-Kaeo; Yeh, Ping-Chun; Lee, Chwan-Ying; Yeh, John; Tang, Denny; Chern, John

2007-03-01

149

Inversion-channel GaAs(100) metal-oxide-semiconductor field-effect-transistors using molecular beam deposited Al2O3 as a gate dielectric on different reconstructed surfaces  

NASA Astrophysics Data System (ADS)

Inversion-channel metal-oxide-semiconductor field-effect-transistors (MOSFETs) have been fabricated using in-situ molecular beam deposited Al2O3 as a gate dielectric directly on freshly molecular beam epitaxy grown Ga-stabilized (4 × 6) and As-covered c(4 × 4) GaAs(100) reconstructed surfaces. The MOSFET using the former surface gives a drain current (Id) of 92 ?A/?m and a transconductance (Gm) of 43 ?S/?m in an 1 ?m gate length configuration; these values are more than 100 times higher than those attained in the MOSFET using the latter surface, which has an Id of 0.47 ?A/?m and a Gm of 0.45 ?S/?m. The enhancement of the inversion currents and Gm may indicate Fermi-level unpinning at the oxide/GaAs(100) interface. The result further confirms that the mid-gap interfacial trap densities of 2 × 1012 eV-1 cm-2 and of exceeding 1013 eV-1cm-2 in the samples on the Ga-stabilized and the As-covered GaAs(100) surfaces, respectively, are correlated to the inversion-channel device performance.

Chang, Y. C.; Chang, W. H.; Merckling, C.; Kwo, J.; Hong, M.

2013-03-01

150

Bipolar Disorder  

MedlinePLUS

... manic-depressive illness, bipolar mood disorder, and bipolar affective disorder are medical terms for the same condition. Bipolar ... depression, or vice versa. Sometimes episodes have a seasonal pattern. Mania in the spring, for example, may ...

151

Carbon doping in molecular beam epitaxy of GaAs from a heated graphite filament  

NASA Astrophysics Data System (ADS)

Carbon doping of GaAs grown by molecular beam epitaxy has been obtained for the first time by use of a heated graphite filament. Controlled carbon acceptor concentrations over the range of 10 to the 17th-10 to the 20th/cu cm were achieved by resistively heating a graphite filament with a direct current power supply. Capacitance-voltage, p/n junction and secondary-ion mass spectrometry measurements indicate that there is negligible diffusion of carbon during growth and with postgrowth rapid thermal annealing. Carbon was used for p-type doping in the base of Npn AlGaAs/GaAs heterojunction bipolar transistors. Current gains greater than 100 and near-ideal emitter heterojunctions were obtained in transistors with a carbon base doping of 1 x 10 to the 19th/cu cm. These preliminary results indicate that carbon doping from a solid graphite source may be an attractive substitute for beryllium, which is known to have a relatively high diffusion coefficient in GaAs.

Malik, R. J.; Nottenberg, R. N.; Schubert, E. F.; Walker, J. F.; Ryan, R. W.

1988-12-01

152

Carbon doping in molecular beam epitaxy of GaAs from a heated graphite filament  

NASA Technical Reports Server (NTRS)

Carbon doping of GaAs grown by molecular beam epitaxy has been obtained for the first time by use of a heated graphite filament. Controlled carbon acceptor concentrations over the range of 10 to the 17th-10 to the 20th/cu cm were achieved by resistively heating a graphite filament with a direct current power supply. Capacitance-voltage, p/n junction and secondary-ion mass spectrometry measurements indicate that there is negligible diffusion of carbon during growth and with postgrowth rapid thermal annealing. Carbon was used for p-type doping in the base of Npn AlGaAs/GaAs heterojunction bipolar transistors. Current gains greater than 100 and near-ideal emitter heterojunctions were obtained in transistors with a carbon base doping of 1 x 10 to the 19th/cu cm. These preliminary results indicate that carbon doping from a solid graphite source may be an attractive substitute for beryllium, which is known to have a relatively high diffusion coefficient in GaAs.

Malik, R. J.; Nottenberg, R. N.; Schubert, E. F.; Walker, J. F.; Ryan, R. W.

1988-01-01

153

Electrical degradation mechanisms of RF power GaAs PHEMTs  

E-print Network

GaAs Pseudomorphic High-Electron Mobility Transistors (PHEMTs) are widely used in RF power applications. Since these devices typically operate at high power levels and under high voltage biasing, their electrical reliability ...

Villanueva, Anita A. (Anita Ariel), 1978-

2007-01-01

154

Effect of graded triple delta-doped sheets on the performance of GaAs based dual channel pseudomorphic high electron mobility transistors  

Microsoft Academic Search

The characteristics of InGaP\\/InGaAs\\/GaAs dual channel pseudomorphic high electron mobility transistors (DCPHEMTs) with different graded triple delta-doped sheets are investigated and experimentally demonstrated. Based on a two-dimensional simulator of ATLAS, the band diagrams, electron densities and DC characteristics of studied devices are comprehensively analyzed. Due to the use of properly graded triple delta-doped sheets, good pinch-off and saturation characteristics, improved

Kuei-Yi Chu; Shiou-Ying Cheng; Meng-Hsueh Chiang; Yi-Jung Liu; Chien-Chang Huang; Tai-You Chen; Chi-Shiang Hsu; Wen-Chau Liu; Wen-Yu Cheng; Bin-Cian Lin

2011-01-01

155

Microwave performance of an optically controlled AlGaAs/GaAs high electron mobility transistor and GaAs MESFET  

NASA Technical Reports Server (NTRS)

Direct current and also the microwave characteristics of optically illuminated AlGaAs/GaAs HEMT are experimentally measured for the first time and compared with that of GaAs MESFET. The results showed that the average increase in the gain is 2.89 dB under 1.7 nW/sq cm optical intensity at 0.83 microns. Further, the effect of illumination on S-parameters is more pronounced when the devices are biased close to pinch off. Novel applications of optically illuminated HEMT as a variable gain amplifier, high speed high frequency photo detector, and mixer are demonstrated.

Simons, Rainee N.; Bhasin, Kul. B.

1987-01-01

156

Ultra-stable oscillator with complementary transistors  

NASA Technical Reports Server (NTRS)

A high frequency oscillator, having both good short and long term stability, is formed by including a piezoelectric crystal in the base circuit of a first bi-polar transistor circuit, the bi-polar transistor itself operated below its transitional frequency and having its emitter load chosen so that the input impedance, looking into the base thereof, exhibits a negative resistance in parallel with a capacitive reactance. Combined with this basic circuit is an auxiliary, complementary, second bi-polar transistor circuit of the same form with the piezoelectric crystal being common to both circuits. By this configuration small changes in quiescent current are substantially cancelled by opposite variations in the second bi-polar transistor circuit, thereby achieving from the oscillator a signal having its frequency of oscillation stable over long time periods as well as short time periods.

Kleinberg, L. L. (inventor)

1974-01-01

157

Bipolar Disorder  

MedlinePLUS

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. ...

158

Bipolar disorder  

MedlinePLUS

Bipolar disorder is a condition in which a person has periods of depression and periods of being extremely ... Bipolar disorder affects men and women equally. It usually starts between ages 15 and 25. The exact cause ...

159

Bipolar Disorder  

MedlinePLUS

... to treat bipolar disorder include mood stabilizers, atypical antipsychotics, and antidepressants. For the most up-to-date ... should be monitored carefully by a doctor. Atypical antipsychotics are sometimes used to treat symptoms of bipolar ...

160

On-Wafer Frequency and Time-Domain Characterization of InGaAs(P)\\/InP Heterojunction Bipolar Transistors and FETs  

Microsoft Academic Search

A probe is designed to achieve frequency- and time-domain measurements on semiconductor devices, e.g. transistors direct on the wafer. Small signal frequency-domain information (s-parameters) were evaluated from pulse responses using Fourier transform algorithms to de-embed the device parameters from the surrounding transmission-line system and excitation pulse imperfections. A corrected time-domain response was obtained by the inverse Fourier transform of the

G. G. MekonnenandH; H. G. Bach

1986-01-01

161

Rapid thermal anneal in InP, GaAs and GaAs/GaAlAs  

NASA Astrophysics Data System (ADS)

Ion implantation in semiconductors provides a doping technique with several advantages over more conventional doping methods and is now extensively used for device applications, e.g. field effect transistors (MESFET GaAs, MIS (InP), GaAs/GaAlAs heterojunction bipolar transistors (HBT). Because of the lattice disorder produced by the implantation, the dopant must be made electrically active by a postimplant anneal. As the device performances are very dependent on its electrical characteristics, the anneal is a very important stage of the process. Rapid anneal is known to provide less exodiffusion and less induffusion of impurities compared to conventional furnace anneal, so this technique has been used in this work to activate an n-type dopant (Si) in InP and a p-type dopant (Mg) in GaAs and GaAs/GaAIAs. These two ions have been chosen to realize implanted MIS InP and the base contacts for GaAs/GaAlAs HBTs. The experimental conditions to obtain the maximum electrical activity in these two cases will be detailed. For example, although we have not been able to obtain a flat profile in Mg + implanted GaAs/GaAlAs heterostructure by conventional thermal anneal, rapid thermal anneal gives a flat hole profile over a depth of 0.5 ?m with a concentration of 1 x 10 19 cm -3.

Descouts, B.; Duhamel, N.; Godefroy, S.; Krauz, P.

162

Metamorphosis of the transistor into a laser  

NASA Astrophysics Data System (ADS)

Based on the invention and operation of the transistor, the alloy diode laser, the quantum-well diode laser and the high-speed heterojunction bipolar transistor (HBT), we have invented and realized now a transistor laser (TL). The transistor laser is a three-terminal technology providing coupling and the coherent light emission in the transistor. The quantum-well (QW) heterojunction bipolar transistor laser, inherently a fast switching device, operates by transporting a small minority base charge density ?1016 \\text{cm}-3 over a nanoscale base thickness (<900 \\text{A}) in picoseconds. The TL, owing to its fast recombination speed, its unique three-terminal configuration, and complementary nature of its optical and electrical collector output signals, enables resonance-free base current and collector voltage modulation. It is a compact source of electro-optical applications such as nonlinear signal mixing, frequency multiplication, negative feedback, and optoelectronics logic gates.

Feng, M.; Holonyak, N., Jr.

2015-01-01

163

IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 50, NO. 3, MARCH 2003 645 Transistor Design and Application Considerations for  

E-print Network

IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 50, NO. 3, MARCH 2003 645 Transistor Design, and Seshadri Subbanna, Member, IEEE Invited Paper Abstract--SiGe HBT transistors achieving over 200 GHz and MAX--BiCMOS integrated circuits, bipolar transistors, heterojunctions, semiconductor devices. I. INTRODUCTION BIPOLAR

Rieh, Jae-Sung

164

Investigations of bipolar magnetotransistor  

NASA Astrophysics Data System (ADS)

(BMT) with well. Investigation by the modem two-dimensional TCAD of the volume SRH-recombination are studied of the lateral bipolar magnetotransistor with the diffusion well for the physicists of working and high sensitivity designs. Magnetic field effect create volume concentration-recombination mechanism of the current negative sensitivity. For raising sensitivity is conduct study of series lateral bipolar magnetotransistor with base in well. Joining the contacts of base and well creates a threshold of operating, negative magnetosensitivity, growing of sensitivity in weak magnetic field. Transistor can serve the generator electron-hole plasma. Device has volumetric generation-recombination mechanism of sensitivity, new principle of getting maximum relative sensitivity on the current 2000 1/T in the magnetic field of the Earth.

Tikhonov, R. D.

2006-05-01

165

The physics of ultrahigh-speed transistors  

Microsoft Academic Search

The speed and efficiency of digital data processing devices is largely determined by the speed of transistors and the degree of integration. Here, the physical principles underlying the operation of bipolar and field-effect transistors as well as hot-electron transistors are examined. In addition to the traditional silicon devices, attention is give to gallium arsenide and other III-V semiconductors and heterostructures

Iu. Pozhela; V. Iutsene

1985-01-01

166

Metal-sulfur-based air-stable passivation of GaAs with very low surface-state densities  

SciTech Connect

An air-stable electronic surface passivation for GaAs and other III-V compound semiconductors that employs sulfur and a suitable metal ion, e.g., Zn, and that is robust towards plasma dielectric deposition has been developed. Initial improvements in photoluminescence are twice that of S-only treatments and have been preserved for >11 months with SiO{sub x}N{sub y} dielectric encapsulation. Photoluminescence and x-ray photoelectron spectroscopies indicate that the passivation consists of two major components with one being stable for >2 years in air. This process improves heterojunction bipolar transistor current gain for both large and small area devices. (c) 2000 American Institute of Physics.

Ashby, Carol I. H. [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States); Zavadil, Kevin R. [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States); Baca, Albert G. [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States); Chang, P.-C. [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States); Hammons, B. E. [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States); Hafich, M. J. [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States)

2000-01-17

167

Simulating Single-Event Upsets in Bipolar RAM's  

NASA Technical Reports Server (NTRS)

Simulation technique saves testing. Uses interactive version of SPICE (Simulation Program with Integrated Circuit Emphasis). Device and subcircuit models available in software used to construct macromodel for an integrated bipolar transistor. Time-dependent current generators placed inside transistor macromodel to simulate charge collection from ion track. Significant finding of experiments is standard design practice of reducing power in unaddressed bipolar RAM cell increases sensitivity of cell to single-event upsets.

Zoutendyk, J. A.

1986-01-01

168

Improvements in the noise temperature of field-effect transistors (FET's) and, later, heterostructure field-effect transistors (HFET's) over the last several decades have been quite dramatic. In 1970, a noise temperature of 120  

E-print Network

, heterostructure field-effect transistors (HFET's) over the last several decades have been quite dramatic. In 1970, GaAs field-effect transistors (FET's) and heterostructure field-effect transistors (HFET's), hotAbstract Improvements in the noise temperature of field-effect transistors (FET's) and, later

Groppi, Christopher

169

Carbon Doping of Indium Gallium Arsenide in Solid - Molecular Beam Epitaxy by Using Carbon Tetrabromide and its Heterojunction Bipolar Transistor Application.  

NASA Astrophysics Data System (ADS)

This thesis presents a systematic study of growth and properties of carbon-doped InGaAs lattice-matched to InP grown by solid-source molecular beam epitaxy (MBE) using carbon tetrabromide (CBr_4). Carbon is an attractive p-type dopant to replace the commonly used beryllium or zinc in GaAs and InGaAs primarily because of its low diffusion coefficient. CBr_4, a gas source, was recently introduced into MBE systems with some promising results in carbon-doped GaAs and in (Al,Ga)As/GaAs HBTs. I have extended the use of CBr_4 in solid-source MBE to study carbon-doped InGaAs lattice-matched to InP and its application in InAlAs/InGaAs HBTs. This work covers the study of carbon doping efficiency, carbon incorporation efficiency, and the minority carrier lifetime comparison in carbon-doped InGaAs layers lattice -matched to InP grown under different conditions. The carbon doping memory effect observed from using CBr_4 in MBE and the application of carbon doping in InAlAs/InGaAs Npn HBTs lattice-matched to InP were also investigated. The results showed that carbon-doped InGaAs grown by MBE has excellent material quality and its application in HBTs is promising. A high dc current gain of 410 with associated incremental gain of 500 for carbon-doped InAlAs/InGaAs HBTs with an 800 A thick base layer doped at 2 times10^{19} {rm cm}^{-1} was achieved. A growth temperature dependent maximum doping density in carbon-doped InGaAs was observed. A hole density as high as 1times10^{20} {rm cm}^{-3} was achieved for carbon-doped InGaAs lattice matched to InP grown at 400^circC. No long -term doping memory effect was observed. The short-term doping memory effect was not observed to affect the HBT device performance.

Hwang, Wen-Yen

170

Bipolar disorder  

Microsoft Academic Search

Bipolar disorder is a pathological disturbance of mood, characterized by waxing and waning manic, depressive and, sometimes distinctly mixed states. A diagnosis of bipolar disorder can only be made with certainty when the manic syndrome declares itself. Most individuals who are diagnosed with this disorder will experience both poles of the illness recurrently, but depressive episodes are the commonest cause

Gérard Emilien; Lucia Septien; Claudine Brisard; Emmanuelle Corruble; Michel Bourin

2007-01-01

171

Bipolar Disorder.  

ERIC Educational Resources Information Center

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…

Spearing, Melissa

172

Bipolar Disorder  

MedlinePLUS

... rapidly, even multiple times in one week. A person who is experiencing a severe bipolar episode may also have psychotic symptoms such as hallucinations or delusions. What are the treatments for bipolar disorder? Recognition and diagnosis of the disorder in its earliest ...

173

A 32-bit RISC implemented in enhancement-mode JFET GaAs  

SciTech Connect

Recently, considerable attention has been focused on gallium arsenide (GaAs) semiconductor process technologies for very high speed digital integrated circuits. This attention is motivated primarily by the ability of GaAs transistors to switch much faster with lower power consumption than transistors in silicon technologies. Soon to be available with higher switching speed and more transistors than the fastest silicon technology (emitter-coupled logic), GaAs digital ICs will be a boon to developers of super-computers and specialized high-speed microprocessors, such as digital signal processors. GaAs transistors are also much more resistant to temperature extremes and to ionizing radiation than silicon, important features for applications requiring operation in harsh environments. This does not mean that GaAs will replace silicon; rather, where the higher cost of GaAs is warranted by application requirements that only GaAs can satisfy, it will augment silicon. The high cost of GaAs chips is due mainly to the scarcity of gallium and the inferior quality and difficulty in manufacturing the gallium arsenide compound. Unlike silicon, which is very uniform and pure, GaAs has many defects and its characteristics may vary considerably from ingot to ingot, affecting yield. Also, the wafers have a tendency to break during processing.

Rasset, T.L.; Niederland, R.A.; Lane, J.H.; Geideman, W.A.

1986-10-01

174

Accelerated life testing and temperature dependence of device characteristics in GaAs CHFET devices  

NASA Technical Reports Server (NTRS)

Accelerated life testing of GaAs complementary heterojunction field effect transistors (CHFET) was carried out. Temperature dependence of single and synchronous rectifier CHFET device characteristics were also obtained.

Gallegos, M.; Leon, R.; Vu, D. T.; Okuno, J.; Johnson, A. S.

2002-01-01

175

A bipolar pulse tester for semiconductor devices  

Microsoft Academic Search

The design and construction of a high voltage pulse generator suitable for bipolar pulse testing of semiconductor devices is described. The apparatus uses field effect transistors as the switching elements in a multistage capacitor discharge circuit based on the Marx generator principle.

S. V. G. Vardigans; D. de Cogan

1986-01-01

176

Bipolar Disorder  

MedlinePLUS

... spending sprees, foolish business investments, or out-of character sexual behavior. • Uncontrollable racing thoughts/rapid speech. Ideas ... logical reasoning). What Causes the Illness? Scientists are learning about the possible causes of bipolar disorder through ...

177

Bipolar Disorder  

MedlinePLUS

... NIH Publication No. TR-08-3679 Share Find Publications About: Bipolar Disorder Related Information Browse Mental Health Topics About NIMH Publications En Español Esta página está disponible en español. ...

178

Cryogenic measurements of aerojet GaAs n-JFETs  

NASA Technical Reports Server (NTRS)

The spectral noise characteristics of Aerojet gallium arsenide (GaAs) junction field effect transistors (JFET's) have been investigated down to liquid-helium temperatures. Noise characterization was performed with the field effect transistor (FET) in the floating-gate mode, in the grounded-gate mode to determine the lowest noise readings possible, and with an extrinsic silicon photodetector at various detector bias voltages to determine optimum operating conditions. The measurements indicate that the Aerojet GaAs JFET is a quiet and stable device at liquid helium temperatures. Hence, it can be considered a readout line driver or infrared detector preamplifier as well as a host of other cryogenic applications. Its noise performance is superior to silicon (Si) metal oxide semiconductor field effect transistor (MOSFET's) operating at liquid helium temperatures, and is equal to the best Si n channel junction field effect transistor (n-JFET's) operating at 300 K.

Goebel, John H.; Weber, Theodore T.

1993-01-01

179

Cryogenic measurements of aerojet GaAs n-JFETs  

NASA Astrophysics Data System (ADS)

The spectral noise characteristics of Aerojet gallium arsenide (GaAs) junction field effect transistors (JFET's) have been investigated down to liquid-helium temperatures. Noise characterization was performed with the field effect transistor (FET) in the floating-gate mode, in the grounded-gate mode to determine the lowest noise readings possible, and with an extrinsic silicon photodetector at various detector bias voltages to determine optimum operating conditions. The measurements indicate that the Aerojet GaAs JFET is a quiet and stable device at liquid helium temperatures. Hence, it can be considered a readout line driver or infrared detector preamplifier as well as a host of other cryogenic applications. Its noise performance is superior to silicon (Si) metal oxide semiconductor field effect transistor (MOSFET's) operating at liquid helium temperatures, and is equal to the best Si n channel junction field effect transistor (n-JFET's) operating at 300 K.

Goebel, John H.; Weber, Theodore T.

1993-09-01

180

Metamorphic materials for indium arsenide transistors  

NASA Astrophysics Data System (ADS)

To improve on both the high frequency and low-power aspects of the III-V semiconductor microwave transistor (by definition, the microwave transistor operates at frequencies above 1 GHz), InAs or a related high indium content alloy is incorporated in the base layer of the heterojunction bipolar transistor (HBT) and the channel layer of the high electron mobility transistor (HEMT). These devices must be fabricated on a semi-insulating (SI) substrate for effective microwave performance which becomes a challenge for the high indium content structures due to the large lattice mismatch with the SI substrates that are commercially available (InP and GaAs). A virtual substrate is engineered which has the desired semi-insulating bulk properties and large lattice parameter template for the epitaxial growth of InAs-based microwave devices. The HBT device, a minority carrier structure, requires a low defect density in the device. This is accomplished with a 0.9 mum compositionally graded InxAl1-xAs (0.52GaAs substrate, which has the advantage of a smoother surface morphology and high resistivity. The large amount of strain (8%) introduced at the interface results in a rhot that decreases linearly with buffer thickness. AlSb CCBLs grown to 0.65, 1.27, and 1.72 mum contain 7.7 x 108, 3.1 x 109, and 5.4 x 109 cm-2 threading dislocations, respectively, in the InAs channels of the HEMT devices. The gate leakage current in the device degrades by a factor of 3 from the low to the high rhot samples. No trend is found with room temperature mobility and rhot , however at low temperatures there is a decrease in mobility with high rho t. The dislocation inhibited mobility is modeled analytically and agrees with experimental results. An alternate approach to creating a narrow bandgap, large lattice parameter virtual substrate is wafer bonding coupled with hydrogen ion implantation and exfoliation. This technique is investigated for metamorphic InAs semiconductors. Key factors taken into consideration are the high diffusivity of hydrogen in the low melting temperature materials and the high density of dislocations in the metamorphic materials. Annealing of the ion implanted metamorphic InAs at 150°C for 10 minutes causes interstitial hydrogen to diffuse away from the implanted region and settle at low energy sites - strained regions around dislocations. Uniform surface blistering is produced at the implantation depth after 5 hours of annealing at 75°C. This effect is explained by the increased diffusivity of hydrogen at higher temperatures.

Noori, Atif M.

181

K-band double-balanced mixer using GaAs HBT THz Schottky diodes  

Microsoft Academic Search

We report on a K-band double-balanced mixer using Schottky diodes made with our baseline (Foundry) GaAs HBT technology. The GaAs HBT MBE structure which yields a transistor fmax of 50 GHz, can also support Schottky diode structures with THz cut-off frequencies. A GaAs HBT Schottky diode double-balanced mixer achieves an upconversion loss of less than 6 dB over an RF

K. W. Kobayashi; R. Kasody; A. K. Oki; S. Dow; B. Allen; D. C. Streit

1994-01-01

182

Cryogenic measurements of aerojet GaAs n-JFETs  

Microsoft Academic Search

The spectral noise characteristics of Aerojet gallium arsenide (GaAs) junction field effect transistors (JFET's) have been investigated down to liquid-helium temperatures. Noise characterization was performed with the field effect transistor (FET) in the floating-gate mode, in the grounded-gate mode to determine the lowest noise readings possible, and with an extrinsic silicon photodetector at various detector bias voltages to determine optimum

John H. Goebel; Theodore T. Weber

1993-01-01

183

Bipolar disorder  

PubMed Central

Bipolar disorder's unique combination of three characteristics - clear genetic diathesis, distinctive clinical features, early availability of an effective treatment (lithium) - explains its special place in the history of psychiatry and its contribution to the current explosive growth of neuroscience. This article looks at the state of the art in bipolar disorder from the vantage point of: (i) genetics (possible linkages on chromosomes 18 and 21q, polygenic hypothesis, research into genetic markers); (ii) diagnosis (new focus on the subjective aspects of bipolar disorder to offset the current trend of underdiagnosis due to overreliance on standardized interviews and rating scales); (iii) outcome (increase in treatment-resistant forms signaling a change in the natural history of bipolar disorder); (iv) pathophysiology (research into circadian biological rhythms and the kindling hypothesis to explain recurrence); (v) treatment (emergence of the anticonvulsants, suggested role of chronic antidepressant treatment in the development of treatment resistance); (vi) neurobiology (evaluation of regulatory function in relation to affective disturbances, role of postsynaptic second-messenger mechanisms, advances in functional neuroimaging); and (vii) psychosocial research (shedding overly dualistic theories of the past to understand the mind and brain as an entity, thus emphasizing the importance of balancing the psychopharmacological and psychotherapeutic approaches). Future progress in the understanding and treatment of bipolar disorder will rely on successful integration of the biological and psychosocial lines of investigation. PMID:22033232

Goodwin, Frederick K.; Ghaemi, S. Nassir

1999-01-01

184

Method for double-sided processing of thin film transistors  

DOEpatents

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.

Yuan, Hao-Chih (Madison, WI); Wang, Guogong (Madison, WI); Eriksson, Mark A. (Madison, WI); Evans, Paul G. (Madison, WI); Lagally, Max G. (Madison, WI); Ma, Zhenqiang (Middleton, WI)

2008-04-08

185

Advancements in bipolar VLSI circuits and technologies  

NASA Astrophysics Data System (ADS)

This paper gives an overview on bipolar circuit/device techniques for VLSI logic and memories. Due to their inherent speed advantage over FETs, bipolar circuits are widely used for high-performance masterslice and custom logic and for high-speed static memory arrays. For logic, traditional circuits such as transistor-transistor logic (TTL) and emitter-coupled logic (ECL) are still mainly applied, but also new circuit technologies such as integrated injection logic or merged transistor logic (I2L/MTL) and Schottky transistor logic (STL) or integrated Schottky logic (ISL) have been devised to manage the VLSI technology constraints. For high-speed memory applications such as caches, local stores, or registers, conventional memory cells are increasingly replaced by more advanced memory devices allowing higher bit densities and lower power dissipation. Significant progress can be expected by technology extensions such as dielectric isolation, multilayer metallization, and polysilicon techniques, in addition to shrinking the devices to 1 micron dimensions or below. Some experimental data and projections indicate the strong potentials of bipolar VLSI.

Wiedmann, S. K.

1984-06-01

186

Bipolar plate battery  

SciTech Connect

This paper describes improvement in an assembled battery including a plurality of bipolar cells. The improvement comprises: conduit means for introducing electrolyte into the bipolar cells, each of the conduit means positioned to be in fluid communication with a different single bipolar cell of the plurality of bipolar cells and to cross over at least one other bipolar cell adjacent the single bipolar cell and acting to introduce electrolyte into the single bipolar cell.

Clough, T.J.; Moulton, R.J.

1991-11-26

187

Developing Low-Noise GaAs JFETs For Cryogenic Operation  

NASA Technical Reports Server (NTRS)

Report discusses aspects of effort to develop low-noise, low-gate-leakage gallium arsenide-based junction field-effect transistors (JFETs) for operation at temperature of about 4 K as readout amplifiers and multiplexing devices for infrared-imaging devices. Transistors needed to replace silicon transistors, relatively noisy at 4 K. Report briefly discusses basic physical principles of JFETs and describes continuing process of optimization of designs of GaAs JFETs for cryogenic operation.

Cunningham, Thomas J.

1995-01-01

188

Magnetic Vortex Based Transistor Operations  

PubMed Central

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

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

2014-01-01

189

Bipolar-Battery Construction  

NASA Technical Reports Server (NTRS)

Bipolar batteries fabricated in continuous quasi-automated process. Components of battery configured so processing steps run sequentially. Key components of battery, bipolar plate and bipolar separator, fabricated separately and later joined together.

Rippel, Wally E.; Edwards, Dean B.

1988-01-01

190

Cayley Bipolar Fuzzy Graphs  

PubMed Central

We introduce the concept of Cayley bipolar fuzzy graphs and investigate some of their properties. We present some interesting properties of bipolar fuzzy graphs in terms of algebraic structures. We also discuss connectedness in Cayley bipolar fuzzy graphs. PMID:24453797

Alshehri, Noura O.

2013-01-01

191

positions): transistor,  

E-print Network

) . Biology & Medicine ­ 4 (psychoanalysis, penicillin, DNA, polio) . Physics & Astronomy ­ 3 (Einstein, Fermi, transistor, plastic, WWW) . Biology & Medicine ­ 4 (psychoanalysis, penicillin, DNA, polio) . Physics

Artemov, Sergei N.

192

A voltage compensated series-gate bipolar circuit operating at sub-2V  

Microsoft Academic Search

A low-voltage series-gate (LSG) bipolar circuit is proposed. A lower-input transistor of the series-gate circuit also acts as a current source transistor. A switching current is compensated for a supply voltage. A 4-b counter using this circuit operates at 500 MHz with the supply voltage of -1.6 V

H. Sato; K. Ueda; N. Sasaki; K. Niwano; H. Shinohara

1993-01-01

193

An introduction GaAs microprocessor architecture for VLSI  

SciTech Connect

Gallium arsenide, or GaAs, technology has recently shown rapid increases in maturity. In particular, the advances made in digital chip complexity have been enormous. This progress is especially evident in two types of chips: static rams and gate arrays. In 1983, static rams containing 1K bits were announced. One year later both a 4K-bit and a 16K-bit version were presented. Gate arrays have advanced from a 1000-gate design presented in 1984 to a 2000-gate design announced in 1985. With this enormous progress underway, it is now appropriate to consider the use of this new technology in the implementation of high-performance processors. GaAs technology generates high levels of enthusiasm primarily because of two advantages it enjoys over silicon: higher speed and greater resistance to adverse environmental conditions. GaAs gates switch faster than silicon transistor-transistor logic, or TTL, gates by nearly an order of magnitude. These switching speeds are even faster than those attained by the fastest silicon emitter-coupled logic, or ECL, but at power levels an order of magnitude lower. For this reason, GaAs is seen to have applications in computer design within several computationally intensive areas. In fact, it has been reported that the Cray-3 will contain GaAs parts. GaAs also enjoys greater resistance to radiation and temperature variations than does silicon. GaAs successfully operates in radiation levels of 10 to 100 million rads. Its operating temperature range extends from -200 to 200/sup 0/C. Consequently, GaAs has created great excitement in the military and aerospace markets.

Milutinovic, V.; Fura, D.; Helbig, W.

1986-03-01

194

Terahertz responsivity of field effect transistors versus their static channel conductivity and loading effects  

E-print Network

effects related to capacitive, inductive, and resistive coupling of the detector to the read-out circuit important ones due to low production costs and the ease of integration in electrical circuits. Recently by all studied III-V (GaAs, GaN) and silicon based transistors. Field effect transistors were recently

Levelut, Claire

195

Total Dose Effects on Bipolar Integrated Circuits at Low Temperature  

NASA Technical Reports Server (NTRS)

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.

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

2012-01-01

196

Comparison of the degradation effects of heavy ion, electron, and cobalt-60 irradiation in an advanced bipolar process  

NASA Technical Reports Server (NTRS)

Experimental measurements are reported of the degradation effects of high-energy particles (heavy Br ions and electrons) and Co-60 gamma-rays on the current gain of minimum-geometry bipolar transistors made from an advanced process. The data clearly illustrate the total-ionizing-dose vs particle-fluence behavior of this bipolar transistor produced by an advanced process. In particular, bulk damage from Co-60 gamma rays in bipolar transistors (base transport factor degradation) and surface damage in bipolar transistors from ionizing radiation (emitter-efficiency degradation) have been observed. The true equivalence between various types of radiation for this process technology has been determined on the basis of damage from the log K1 intercepts.

Zoutendyk, John A.; Goben, Charles A.; Berndt, Dale F.

1988-01-01

197

On the inversion in GaAs metal-insulator-semiconductor heterostructures  

SciTech Connect

We report the discovery that the [111] strained Si ({approximately}10 {Angstrom}) as an interlayer between Si{sub 3}N{sub 4} and (111) GaAs may allow the Fermi level to fully scan the GaAs conduction band and induce inversion electrons in GaAs. The band structure calculations indicate that the strained Si on (111) GaAs or (111) AlGaAs has a much wider band gap (0.87 eV) than the strained Si on (001) GaAs (0.34 eV). The energy levels in the quantum well formed by Si{sub 3}N{sub 4}/Si/(111)GaAs are almost unconfined and those of Si{sub 3}N{sub 4}/Si/Al{sub 0.3}Ga{sub 0.7}As/(111)GaAs are confined, but the confined energy level in Si conduction band is {approximately}0.1 eV higher than the GaAs conduction band. Both structures may induce inversion electrons in GaAs potentially paving the way for the realization of GaAs based n-channel inversion mode metal-insulator-semiconductor transistors. {copyright} {ital 1997 American Institute of Physics.}

Chen, Z.; Noor. Mohammad, S.; Park, D.; Morkoc, H. [Coordinated Science Laboratory and Materials Research Laboratory, University of Illinois at Urbana-Champaign, 1101 West Springfield Avenue, Urbana, Illinois 61801 (United States)] [Coordinated Science Laboratory and Materials Research Laboratory, University of Illinois at Urbana-Champaign, 1101 West Springfield Avenue, Urbana, Illinois 61801 (United States); Chang, Y. [Materials Research Laboratory and Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801 (United States)] [Materials Research Laboratory and Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801 (United States)

1997-01-01

198

Analysis and Optimization of Lateral Thin-Film Silicon-on-Insulator (SOI) PMOS Transistor with  

E-print Network

to bipolar transistor and its ease of integration with CMOS technology. P-channel LDMOS (LDPMOS) transistors-type floating layer associated with a field plate defines the double RESURF [5] which leads to competitive Ron of the field plate is possible and the doping concentration of the drift region which sustains the voltage has

Paris-Sud XI, Université de

199

Bipolar fuzzy finite state machines  

Microsoft Academic Search

As a generalization of a fuzzy finite state machine, the notion of a bipolar fuzzy finite state machine is introduced. Also, the concepts of a bipolar (immediate) successor, a bipolar exchange property and a bipolar subsystem are introduced. Some related properties are discussed. A condition for a bipolar fuzzy finite state machine to satisfy the bipolar exchange property is established.

Young Bae Jun; Jacob Kavikumarb

200

Noise characteristics of gallium arsenide field-effect transistors  

Microsoft Academic Search

Small signal and noise characteristics for GaAs field-effect transistors are derived with the saturated drift velocity of the carriers underneath the gate taken into account. The noise contributed by the saturated carriers is nonnegligible and in most cases, exceeds the noise generated by the unsaturated region. Parasitic elements contribute importantly by preventing the full cancellation of the correlated noise of

H. Statz; H. A. Haus; R. A. Pucel

1974-01-01

201

A 3.5GHz Power Amplifier Module Using Directly-Ion-Implanted GaAs MESFET Technology for Wireless Communications  

Microsoft Academic Search

GaAs power amplifier modules are the main components in the transmitter of a wireless com- munication system.High-performance GaAs power transistors play an important role for design of advanced GaAs power amplifier modules.The ion implantation technologies including selective and direct implantation approaches have the advantages of high uniformity, high throughput, and low costs over the epitaxial technologies for fabrication of microwave

Y.-L. Lai; D.-G. Liu; M.-S. Shiau; S.-Y. Yang

2000-01-01

202

Bipolar Disorder in Adults  

MedlinePLUS

... to treat bipolar disorder include mood stabilizers, atypical antipsychotics, and antidepressants. For the most up-to-date ... should be monitored carefully by a doctor. Atypical antipsychotics are sometimes used to treat symptoms of bipolar ...

203

GaAs Optoelectronic Integrated-Circuit Neurons  

NASA Technical Reports Server (NTRS)

Monolithic GaAs optoelectronic integrated circuits developed for use as artificial neurons. Neural-network computer contains planar arrays of optoelectronic neurons, and variable synaptic connections between neurons effected by diffraction of light from volume hologram in photorefractive material. Basic principles of neural-network computers explained more fully in "Optoelectronic Integrated Circuits For Neural Networks" (NPO-17652). In present circuits, devices replaced by metal/semiconductor field effect transistors (MESFET's), which consume less power.

Lin, Steven H.; Kim, Jae H.; Psaltis, Demetri

1992-01-01

204

Cryogenic Low Noise Amplifier with GaAs JFETs  

NASA Astrophysics Data System (ADS)

A SONY n-type GaAs junction field effect transistor (JFET) can operate at deep cryogenic temperatures without exhibiting kink phenomena or hysteresis in its I-V characteristics. Further the GaAs JFET has small gate leakage currents(<4.6×10-19A) and a minute input capacitance (0.037 pF). Moreover, even though the gate terminal of a JFET is surrounded by high-impedance materials, the noise level does not increase and a low noise level of ˜500 nV/Hz1/2 at 1 Hz with low power dissipation (<1 ?W) was achieved. We are currently developing operational amplifiers (Op-Amps) and digital modules for cryogenically cooled high-sensitivity photodetection systems. The GaAs Op-Amp with an open loop gain of 2000 at a power dissipation of 6.5 ?W has been developed.

Fujiwara, Mikio; Nagata, Hirohisa; Hibi, Yasunori; Matsuo, Hiroshi; Sasaki, Masahide

2009-12-01

205

Equivalent bipolar fuzzy relations  

Microsoft Academic Search

We consider a relation between bipolar fuzzy relations (originally called intuitionistic fuzzy relations). This relation turns out to be an equivalence in the family of all bipolar fuzzy relations in a given (crisp) set. It also has many other properties which seem to be useful in applications. We study standard properties of bipolar fuzzy relations in the context of the

Urszula Dudziak; Barbara Pekala

2010-01-01

206

Progress on GaAs cryogenic readout circuits for SISCAM  

NASA Astrophysics Data System (ADS)

We are developing cryogenic readout circuits for the array of superconducting tunneling junctions (STJs) at submillimeter wavelength SISCAM (Superconductive Imaging Submillimeter-wave CAMera). A current conceptual design of SISCAM will employ a direct hybrid array system just like CMOS image sensors widely used at optical and infrared wavelength. Because of relatively large impedance of the STJ fabricated by RIKEN (~10 M? in a dark condition), it requires readout preamplifier with low current noise. Therefore, it is not suitable for the STJ to use a readout system by Superconductive Quantum Interferences Devices as for Transition Edge Sensor. Instead, we selected capacitive transimpedance amplifier (CTIA) using a SONY n-type GaAs Junction Field Effect Transistor (JFET). However, the CTIA has not been used as the readout of the STJ. Therefore, we measured the photocurrent of the STJ by the CTIA with Silicon JFETs and by transimpedance amplifier (TIA), which is a conventional readout for the STJ, in the same bias condition, and confirmed both results are in good agreement. Additionally, we report development of readout integrated circuits with GaAs JFETs. In order to design the CTIA circuit with the GaAs JFETs, we fabricated the independent GaAs JFETs and matched pairs of them. We measured electrical characteristics of these GaAs JFETs at the cryogenic temperatures less than 4.2 K. We demonstrated performance of an operational amplifier fabricated with the GaAs JFETs measuring a differential amplifier with the dual GaAs JFET, and additionally estimate amplifier gain, offset voltage, and power consumption of the CTIA by the circuit simulation using the PSPICE. In consequence, the expected performance fulfills the requirements for the readout amplifier of the STJs except for the noise performance.

Nagata, H.; Kobayashi, J.; Matsuo, H.; Fujiwara, M.

2006-06-01

207

Improved Design and Characterization Method for Very High Speed Bipolar Circuits  

Microsoft Academic Search

An improved design method for high speed bipolar circuits is presented. It uses iso base-collector capacitance curves superposed to the duty cycles plots in the (Ic,Vce) plane. This new optimization way gives the optimum operating region for each transistor of a bipolar circuit to reach the best trade-off between the switching speed and the power consumption. Electrical design of emitter-coupled

Abed-Elhak Kasbari; A. Ouslimani; S. Blayac; A. Konczykowska

2008-01-01

208

Suicide and bipolar disorder  

Microsoft Academic Search

Bipolar disorders are common illnesses with markedly elevated premature mortality, but they remain frequently under-referred,\\u000a under-diagnosed, and under-treated. Suicide is the cause of death in up to 15% of patients with bipolar disorders, and about\\u000a half of them make at least one suicide attempt in their lifetime. The suicide rate of (untreated) bipolar patients is 25 times\\u000a higher than the

Zoltán Rihmer

209

Experimental determination of single-event upset (SEU) as a function of collected charge in bipolar integrated circuits  

NASA Technical Reports Server (NTRS)

Single-Event Upset (SEU) in bipolar integrated circuits (ICs) is caused by charge collection from ion tracks in various regions of a bipolar transistor. This paper presents experimental data which have been obtained wherein the range-energy characteristics of heavy ions (Br) have been utilized to determine the cross section for soft-error generation as a function of charge collected from single-particle tracks which penetrate a bipolar static RAM. The results of this work provide a basis for the experimental verification of circuit-simulation SEU modeling in bipolar ICs.

Zoutendyk, J. A.; Malone, C. J.; Smith, L. S.

1984-01-01

210

A voltage compensated series-gate bipolar circuit operating at sub-2 V  

Microsoft Academic Search

A low-voltage series-gate (LSG) bipolar circuit is proposed. A lower-input transistor of the series-gate circuit acts as a current source transistor. The lower-input is driven by a VEE-traced buffer (VTB). The DC characteristics of the VTB output trace the change in a power supply voltage VEE. The switching current of the series-gate circuit is stable while VEE changes. The design

H. Sato; K. Ueda; N. Sasaki; T. Ikeda; K. Mashiko

1994-01-01

211

A 20GHz Bipolar Latched Comparator With Improved Sensitivity Implemented in InP HBT Technology  

Microsoft Academic Search

A method for improving the sensitivity (or speed) of a master-slave emitter-coupled logic comparator using emitter de- generation resistors is presented. The degeneration resistors in the latching pair reduce the transistor charging time, thus allowing more time for regeneration. Improved and standard comparators were implemented using the InP\\/GaInAs heterojunction bipolar transistor technology and were tested at a clock rate of

Shraga Kraus; Ingmar Kallfass; Robert E. Makon; Rachid Driad; Michael Moyal; Dan Ritter

2011-01-01

212

A high power S-band bipolar amplifier  

NASA Astrophysics Data System (ADS)

Substantial efforts are currently under way to apply monolithic process technology to the fabrication of T/R modules at different frequencies to reduce size and module cost. While recent progress in MMIC phase shifters and low noise amplifiers makes these components a likely choice for an S-band T/R module, the RF power requirements are much more difficult to satisfy in monolithic form. Since the emphasis in the power amplifier is on high efficiency and high peak power, bipolar transistors operating in class C are much better suited for high RF power applications. The capability of hybrid circuits using bipolar transistors and high Q matching networks to achieve high peak pulsed power and high efficiency at S band is demonstrated. This performance may make it feasible to replace tubes with all solid-state T/R modules in modern multifunction phased-array radars.

Fathy, Aly; Kalokitis, David

1989-06-01

213

Modeling of enclosed-gate layout transistors as ESD protection device based on conformal mapping method  

NASA Astrophysics Data System (ADS)

This paper proposes a novel technique for modeling the electrostatic discharge (ESD) characteristic of the enclosed-gate layout transistors (ELTs). The model consists of an ELT, a parasitic bipolar transistor, and a substrate resistor. The ELT is decomposed into edge and corner transistors by solving the electrostatic field problem through the conformal mapping method, and these transistors are separately modeled by BSIM (Berkeley Short-channel IGFET Model). Fast simulation speed and easy implementation is obtained as the model can be incorporated into standard SPICE simulation. The model parameters are extracted from the critical point of the snapback curve, and simulation results are presented and compared to experimental data for verification.

Jia, Zhang; Haigang, Yang; Jiabin, Sun; Le, Yu; Yuanfeng, Wei

2014-08-01

214

Costs of Bipolar Disorder  

Microsoft Academic Search

Bipolar disorder is a chronic affective disorder that causes significant economic burden to patients, families and society. It has a lifetime prevalence of approximately 1.3%. Bipolar disorder is characterised by recurrent mania or hypomania and depressive episodes that cause impairments in functioning and health-related quality of life. Patients require acute and maintenance therapy delivered via inpatient and outpatient treatment. Patients

Leah S. Kleinman; Ana Lowin; Gian Gandhi; Eric Edgell; Dennis A. Revicki

2003-01-01

215

[Atypical bipolar disorders].  

PubMed

Some epidemiologic data reveal how difficult detecting atypic bipolar disorders is: 9 years of progression before the diagnosis is properly established and a specific treatment is initiated, and intervention of 4 to 5 different specialists. Incomplete symptomatology, impulsive actions, periodic alcohol abuse, compulsive buying behaviors, acute delusional episodes, medicolegal actions and comorbidities can hide or modify bipolar symptomatology. Bipolarity should be systematically screened for in case of substance abuse (40 to 60 percent of bipolar disorders), anxiety disorders (panic disorder, generalized anxiety, obsessive-compulsive disorders etc.) and feeding disorders. In these various situations, history taking and clinical examination will help to detect signs of bipolarity: reaction to antidepressants, inefficiency, paradoxical worsening, development of behavior disorders and mood changes. Besides screening for thymic disorders, the examination will be completed by history taking of thymic disorders, suicide, toxic abuse, anxiety disorders, personal history of attention deficit hyperactivity disorder in childhood, depression or postpartum psychosis in women, as well as premenstrual depressive manifestations. PMID:19462868

Gay, Christian

2009-04-20

216

Actigraphy in Remitted Bipolar Patients SLEEP IN REMITTED BIPOLAR DISORDER  

E-print Network

Actigraphy in Remitted Bipolar Patients 1 SLEEP IN REMITTED BIPOLAR DISORDER: A NATURALISTIC CASE euthymic BD cases from HC. 6 keywords: bipolar disorder; actigraphy; euthymia; remission; sleep; circadian Bipolar disorder (BD) is a severe mental disorder and the worldwide prevalence of the BD spectrum is 1

Boyer, Edmond

217

Bipolar Disorder and Substance Abuse  

Microsoft Academic Search

Objectives: To review evidence about mechanisms and consequences of relationships between bipolar and substance use disorders.Methods: Articles were identified using a MEDLINE search linking (1) bipolar disorder to substance use disorders, alcoholism, and specific drugs, (2) bipolar disorder and substance abuse to treatment strategies, and (3) bipolar disorder or substance abuse to behavioral sensitization, impulsivity, and suicide. We attempted to

Alan C. Swann

2005-01-01

218

Structural properties and band offset determination of p-channel mixed As/Sb type-II staggered gap tunnel field-effect transistor structure  

E-print Network

field scattering in AlGaN/AlN/GaN heterostructure field-effect transistors Appl. Phys. Lett. 101, 113501-channel staggered gap In0.7Ga0.3As/ GaAs0.35Sb0.65 heterostructure tunnel field-effect transistor (TFET) grown tunnel field-effect transistor structure Y. Zhu, N. Jain, D. K. Mohata, S. Datta, D. Lubyshev et al

Yener, Aylin

219

Bipolar Disorder in Children  

PubMed Central

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

2014-01-01

220

(Yin) (Yang) bipolar fuzzy sets  

Microsoft Academic Search

A bipolar fuzzy set theory is introduced in the space {?(x,y)|(x,y)?[-1,0]×[0,1]}. Two types of bipolar ?-cuts are proposed. Resolutions of bipolar level sets and their relationships are established. The bipolar fuzzy set theory combines both polarity and fuzziness into a unified model and therefore, provides a theoretical basis for bipolar clustering, conflict resolution, and multiagent coordination

W.-R. Zhang

1998-01-01

221

Misdiagnosis of Bipolar Disorder  

PubMed Central

The objective of this article is to review the literature on one of the most complex topics in contemporary psychiatry—the diagnosis of bipolar disorder. Bipolar disorder is a disabling psychiatric illness that is often misdiagnosed, especially on initial presentation. Misdiagnosis results in ineffective treatment, which further worsens the outcome. Major contributors toward misdiagnosis include lapses in history-taking, presence of psychiatric and medical comorbidities, and limitations in diagnostic criteria. Careful screening for symptoms of hypomania/mania and clinical features suggestive of bipolarity as well as use of collateral history and screening instruments, such as mood questionnaires, might help in limiting the rate of misdiagnosis. PMID:20877548

Rajput, Muhammad

2006-01-01

222

Hardness assurance and testing issues for bipolar/BiCMOS devices  

SciTech Connect

The dose-rate dependence of the total-dose response of bipolar transistors is mapped for several dose rates. comparisons are made between the total-dose response in x-ray and [sup 60]Co irradiations. Implications for hardness assurance are discussed.

Nowlin, R.N.; Schrimpf, R.D. (Arizona Univ., Tucson, AZ (United States). Dept. of Electrical and Computer Engineering); Fleetwood, D.M. (Sandia National Labs., Albuquerque, NM (United States)); Pease, R.L. (Mission Research Corp., Albuquerque, NM (United States)); Combs, W.E. (Naval Surface Warfare Center, Crane, IN (United States))

1993-01-01

223

Bipolar thermoelectric devices  

E-print Network

The work presented here is a theoretical and experimental study of heat production and transport in bipolar electrical devices, with detailed treatment of thermoelectric effects. Both homojunction and heterojunction devices ...

Pipe, Kevin P. (Kevin Patrick), 1976-

2004-01-01

224

A silicon nanocrystal tunnel field effect transistor  

SciTech Connect

In this work, we demonstrate a silicon nanocrystal Field Effect Transistor (ncFET). Its operation is similar to that of a Tunnelling Field Effect Transistor (TFET) with two barriers in series. The tunnelling barriers are fabricated in very thin silicon dioxide and the channel in intrinsic polycrystalline silicon. The absence of doping eliminates the problem of achieving sharp doping profiles at the junctions, which has proven a challenge for large-scale integration and, in principle, allows scaling down the atomic level. The demonstrated ncFET features a 10{sup 4} on/off current ratio at room temperature, a low 30?pA/?m leakage current at a 0.5?V bias, an on-state current on a par with typical all-Si TFETs and bipolar operation with high symmetry. Quantum dot transport spectroscopy is used to assess the band structure and energy levels of the silicon island.

Harvey-Collard, Patrick, E-mail: P.Collard@USherbrooke.ca [Département de Physique, Université de Sherbrooke, 2500 Boulevard de l'Université, Sherbrooke, Quebec J1K 2R1 (Canada); Institut Interdisciplinaire d'Innovation Technologique (3IT), Université de Sherbrooke, 3000 Boulevard de l'Université, Sherbrooke, Quebec J1K 0A5 (Canada); Laboratoire Nanotechnologies Nanosystèmes (LN2)–CNRS UMI-3463, Université de Sherbrooke, 3000 Boulevard de l'Université, Sherbrooke, Quebec J1K 0A5 (Canada); Drouin, Dominique [Institut Interdisciplinaire d'Innovation Technologique (3IT), Université de Sherbrooke, 3000 Boulevard de l'Université, Sherbrooke, Quebec J1K 0A5 (Canada); Laboratoire Nanotechnologies Nanosystèmes (LN2)–CNRS UMI-3463, Université de Sherbrooke, 3000 Boulevard de l'Université, Sherbrooke, Quebec J1K 0A5 (Canada); Pioro-Ladrière, Michel [Département de Physique, Université de Sherbrooke, 2500 Boulevard de l'Université, Sherbrooke, Quebec J1K 2R1 (Canada); CIFAR Program in Quantum Information Science, Canadian Institute for Advanced Research (CIFAR), Toronto, Ontario M5G 1Z8 (Canada)

2014-05-12

225

A 600-MHz median-type digital filter on GaAs  

NASA Technical Reports Server (NTRS)

A single-chip GaAs implementation of an FIR-median hybrid filter is presented. The very high-speed digital filter combines linear averaging structures to a median selector. The filter operates on 5-b samples with ECL-compatible I/O interfaces. The 1500-transistor LSI device with 3.6-sq mm chip size was processed with a 1.0-micron GaAs depletion-mode (D-mode) MESFET process. The filter demonstrates 600-MHz sample rate when operated in test mode utilizing special built-in feedback.

Vainjo, Olli; Sundaram, Mani; Long, Stephen I.; Neuvo, Yrjo

1992-01-01

226

Staging Bipolar Disorder  

Microsoft Academic Search

The purpose of this study was to analyze the evidence supporting a staging model for bipolar disorder. The authors conducted\\u000a an extensive Medline and Pubmed search of the published literature using a variety of search terms (staging, bipolar disorder,\\u000a early intervention) to find relevant articles, which were reviewed in detail. Only recently specific proposals have been made\\u000a to apply clinical

Eduard Vieta; M. Reinares; A. R. Rosa

2011-01-01

227

Outlook and emerging semiconducting materials for ambipolar transistors.  

PubMed

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. PMID:24591008

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

2014-02-26

228

An all-implanted, self-aligned, GaAs JFET with a nonalloyed W/p[sup +]-GaAs ohmic gate contact  

SciTech Connect

The authors describe a self-aligned, refractory metal gate contact, enhancement mode, GaAs junction field effect transistor (JFET) where all impurity doping was done by ion implantation. Processing conditions are presented for realizing a high gate turn on voltage ([approximately]1.0 V at 1 mA/mm of gate current) relative to GaAs MESFET's. The high gate turn-on voltage is the result of optimizing the p+-gate implant and anneal to achieve a nonalloyed ohmic contact between the implanted p[sup +]-GaAs and the sputter deposited tungsten gate contact. Initial nominally 1.0 [mu]m [times] 50 [mu]m n-JFET's have a transconductance of 85 mS/mm and f[sub t] of 11.4 GHz.

Zolper, J.C.; Baca, A.G.; Shul, R.J.; Howard, A.J.; Rieger, D.J.; Sherwin, M.E.; Lovejoy, M.L.; Hjalmarson, H.P.; Draper, B.L.; Klem, J.F.; Hietala, V.M. (Sandia National Labs., Albuquerque, NM (United States))

1994-07-01

229

Active gate voltage control of turn-on di\\/dt and turn-off dv\\/dt in insulated gate transistors  

Microsoft Academic Search

As the characteristics of insulated gate transistors [like metal-oxide-semiconductor field-effect transistors and insulated gate bipolar transistors (IGBTs)] have been constantly improving, their utilization in power converters operating at higher and higher frequencies has become more common. However, this, in turn, leads to fast current and voltage transitions that generate large amounts of electromagnetic interferences over wide frequency ranges. In this

Nadir Idir; Robert Bausière; Jean Jacques Franchaud

2006-01-01

230

Genetics of bipolar disorder  

PubMed Central

Bipolar disorder (also known as manic depressive illness) is a complex genetic disorder in which the core feature is pathological disturbance in mood (affect) ranging from extreme elation, or mania, to severe depression usually accompanied by disturbances in thinking and behaviour. The lifetime prevalence of 1% is similar in males and females and family, twin, and adoption studies provide robust evidence for a major genetic contribution to risk. There are methodological impediments to precise quantification, but the approximate lifetime risk of bipolar disorder in relatives of a bipolar proband are: monozygotic co-twin 40-70%; first degree relative 5-10%; unrelated person 0.5-1.5%. Occasional families may exist in which a single gene plays the major role in determining susceptibility, but the majority of bipolar disorder involves the interaction of multiple genes (epistasis) or more complex genetic mechanisms (such as dynamic mutation or imprinting). Molecular genetic positional and candidate gene approaches are being used for the genetic dissection of bipolar disorder. No gene has yet been identified but promising findings are emerging. Regions of interest identified in linkage studies include 4p16, 12q23-q24, 16p13, 21q22, and Xq24-q26. Chromosome 18 is also of interest but the findings are confusing with up to three possible regions implicated. To date most candidate gene studies have focused on neurotransmitter systems influenced by medication used in clinical management of the disorder but no robust positive findings have yet emerged. It is, however, almost certain that over the next few years bipolar susceptibility genes will be identified. This will have a major impact on our understanding of disease pathophysiology and will provide important opportunities to investigate the interaction between genetic and environmental factors involved in pathogenesis. This is likely to lead to major improvements in treatment and patient care but will also raise important ethical issues that will need to be addressed.???Keywords: bipolar disorder; manic depressive illness PMID:10465107

Craddock, N.; Jones, I.

1999-01-01

231

Bipolar fuzzy subalgebras and bipolar fuzzy ideals of BCK\\/BCI-algebras  

Microsoft Academic Search

The notion of bipolar fuzzy subalgebras and bipolar fuzzy ideals of a BCK\\/BCI-algebra is introduced, and several properties are investigated. Relations between a bipolar fuzzy subalgebra and a bipolar fuzzy ideal are given. A condition for bipolar fuzzy subalgebra to be a bipolar fuzzy ideal is provided, and the characterizations of a bipolar fuzzy ideal are stated. The concept of

Kyoung Ja Lee

2008-01-01

232

Lightweight bipolar storage battery  

NASA Technical Reports Server (NTRS)

An apparatus [10] is disclosed for a lightweight bipolar battery of the end-plate cell stack design. Current flow through a bipolar cell stack [12] is collected by a pair of copper end-plates [16a,16b] and transferred edgewise out of the battery by a pair of lightweight, low resistance copper terminals [28a,28b]. The copper terminals parallel the surface of a corresponding copper end-plate [16a,16b] to maximize battery throughput. The bipolar cell stack [12], copper end-plates [16a,16b] and copper terminals [28a,28b] are rigidly sandwiched between a pair of nonconductive rigid end-plates [20] having a lightweight fiber honeycomb core which eliminates distortion of individual plates within the bipolar cell stack due to internal pressures. Insulating foam [30] is injected into the fiber honeycomb core to reduce heat transfer into and out of the bipolar cell stack and to maintain uniform cell performance. A sealed battery enclosure [ 22] exposes a pair of terminal ends [26a,26b] for connection with an external circuit.

Rowlette, John J. (Inventor)

1992-01-01

233

Yinyang Bipolar Lattices and L-sets for Bipolar Knowledge Fusion, Visualization, and Decision  

Microsoft Academic Search

YinYang bipolar sets, bipolar lattice, bipolar L-crisp sets, and Bipolar L-fuzzy sets are presented for bipolar information\\/knowledge fusion, visualization, and decision. First, a bipolar lattice B is defined as a 4-tuple (B, ?, &, ?) in which every pair of elements has a bipolar lub (blub ?), a bipolar glb (bglb &), and a cross-pole glb (cglb ?). A bipolar

Wen-ran Zhang

2005-01-01

234

High Power GaAs FET Solid State Amplifier (32 watt) Development Program  

Microsoft Academic Search

A High Power Solid State Amplifier (HPSSA) using Gallium Arsenide Field Effect Transistors (GaAs FETs) has been developed to compete with the 40 watt TWTAs on the Defense Satellite Communications System III (DSCS III), the latest generation of United States Military Communications Satellites. The Engineering Model of this state-of-the-art component demonstrates that it is competitive with the 40 watt TWTA

W. Joseph Soo Hoo

1986-01-01

235

Bipolar battery construction  

NASA Technical Reports Server (NTRS)

A lightweight, bipolar battery construction for lead acid batteries in which a plurality of thin, rigid, biplates each comprise a graphite fiber thermoplastic composition in conductive relation to lead stripes plated on opposite flat surfaces of the plates, and wherein a plurality of nonconductive thermoplastic separator plates support resilient yieldable porous glass mats in which active material is carried, the biplates and separator plates with active material being contained and maintained in stacked assembly by axial compression of the stacked assembly. A method of assembling such a bipolar battery construction.

Rippel, Wally E. (Inventor); Edwards, Dean B. (Inventor)

1981-01-01

236

Ion implantation processing for high-speed GaAs JFETs  

SciTech Connect

GaAs Junction Field Effect Transistors (JFETs) offer a higher gate turn-on voltage, resulting in a better noise margin and reduced power dissipation, than the more widely employed GaAs MESFET. The primary reason the JFET has not been more widely used is the speed penalty associated with the gate/channel junction and corresponding gate length broadening. We present the ion implantation processes used for a self-aligned, all ion-implanted, GaAs JFET that minimizes the speed penalty for the JFET while maintaining the advantageous higher gate turn-on voltage. Process characterization of the p{sub +}-gate implant done with either Mg, Zn, or Cd along with the co-implantation of P is presented. In addition, a novel backside channel confinement technology employing ion-implanted carbon is discussed. Complete JFET device results are reported.

Zolper, J.C.; Baca, A.G.; Sherwin, M.E.; Shul, R.J.

1995-07-01

237

Characterization of power transistors as high dose dosimeters  

NASA Astrophysics Data System (ADS)

A bipolar transistor, previously investigated as a possible radiation dosimeter and tested under industrial irradiation conditions in high-activity gamma and high-energy, high-power electron beam facilities has been subjected to stability test in order to understand its behaviour and help to improve its performances. Charge carrier lifetime was measured for several sets of transistors which were then irradiated with various doses (3-60 kGy): seven sets with 60Co gamma rays and eight with a 10 MeV electron beam. After irradiation all the transistors were measured and each set was divided into three groups: one group was left untreated, the second group was heated at 100 °C for 30 minutes and the third group was heated at 150 °C for 30 minutes, for testing the stability of the lifetime. Our data showed that heat treatment quite successfully eliminates post-irradiation changes in the response. Response measurements of the irradiated transistors, heat-treated and untreated, were carried out at room temperature over several weeks after irradiation to establish post-irradiation stability and assess if these transistors could be used for recording dose history. Calibration curves in the range 3-60 kGy for the thermally treated and untreated devices are presented. Dependence of the response of the transistors on the temperature of the measurements in the range 20-50 °C is reported.

Fuochi, P. G.; Lavalle, M.; Corda, U.; Kovacs, A.; Peimel-Stuglik, Z.; Gombia, E.

2009-02-01

238

Temperature dependence of electronic behaviors in quantum dimension junctionless thin-film transistor  

PubMed Central

The high temperature dependence of junctionless (JL) gate-all-around (GAA) poly-Si thin-film transistors (TFTs) with 2-nm-thick nanosheet channel is compared with that of JL planar TFTs. The variation of SS with temperature for JL GAA TFTs is close to the theoretical value (0.2 mV/dec/K), owing to the oxidation process to form a 2-nm-thick channel. The bandgap of 1.35 eV in JL GAA TFTs by fitting experimental data exhibits the quantum confinement effect, indicating greater suppression of Ioff than that in JL planar TFTs. The measured ?Vth?T of ?1.34 mV/°C in JL GAA nanosheet TFTs has smaller temperature dependence than that of ?5.01 mV/°C in JL planar TFTs. PMID:25147491

2014-01-01

239

Radiation effect on silicon transistors in mixed neutrons-gamma environment  

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

240

Using SPICE for the modelization of the static behaviour of the insulated gate transistor  

E-print Network

L-907 Using SPICE for the modelization of the static behaviour of the insulated gate transistor F simulation de circuits (SPICE) est présentée ci-dessous. Le comportement statique d'un composant bipolaire program (SPICE) is presented. The static behaviour of a complex bipolar device (COMFET or IGT) is analysed

Boyer, Edmond

241

High-voltage, high-speed switching transistors using current-mode second breakdown  

NASA Astrophysics Data System (ADS)

Current mode second breakdown is a fast negative resistance phenomenon which occurs in bipolar epitaxial transistors and which can be used to generate fast rise time electrical pulses. A study of this effect and the design of devices capable of generating pulses of greater than 500 volts with 3 to 4 ns rise time is described.

Pocha, M. D.; Koo, J. C.

1983-02-01

242

High-frequency resonant transistor dc-dc converters  

NASA Astrophysics Data System (ADS)

The design of a transistor dc-dc resonant converter operating at 200-300 kHz is presented, and the operation of a 500-W breadboard version is reported. Several configurations of both voltage-input and current-input type are described and illustrated with circuit diagrams and waveforms, and a full-bridge voltage-input resonant inverter using gate turnoff devices is analyzed in detail, using a piecewise linear approach to obtain design curves. The performance of the breadboard voltage-input half bridge using FET power switches is shown in graphs, demonstrating the low switching losses and transistor stresses achieved by lossless-snubber design. It is predicted that similar designs using bipolar transistors or GTOs can attain energy efficiencies greater than 90 percent. Applications to switching power supplies and battery chargers are suggested.

Steigerwald, R. L.

1984-05-01

243

Neutron damage equivalence for silicon, silicon dioxide, and GaAs  

NASA Astrophysics Data System (ADS)

Displacement-energy and ionization-energy transfers to Si, SiO2, and GaAs as functions of incident neutron energy were calculated using cross-section data and fine group structure in the NJOY code system. Neutron spectra determinations for several reactor neutron environments were made using activation cross sections and a novel technique with the SAND II code. Measurements of carrier-removal rates in GaAs and of Si transistor gain degradation were made in representative neutron environments. Experimental results are compared to damage ratios predicted with the spectra and NJOY displacement functions. For fission-like spectra, calculated Si damage ratios are in good agreement with those determined with ASTM E722-85 and with measured transistor damage ratios. Significant differences are found between Si NJOY and ASTM E722-85 for 14-MeV-to-reactor neutron damage ratios; NJOY gives better agreement with experimental data reported in the literature. In GaAs, 14-MeV-to-reactor experimental damage ratios are smaller than predicted by calculated displacement ratios. This suggests that a more complex model of damage for majority carrier removal in GaAs is required. The use of incorrect damage functions is shown to adversely affect simulation fidelity in some representative neutron environments.

Luera, Theodore F.; Kelly, John G.; Stein, Herman J.; Lazo, Maximo S.; Lee, Clarence E.

1987-12-01

244

Stainless steel bipolar plates  

Microsoft Academic Search

In this research, a specific surface modification technology was developed for stainless steel bipolar plates to obtain a corrosion-resistant oxide film. The surface roughness was measured, and an electron spectroscopy analysis (ESCA) was conducted to verify the chemical composition of the surface layer. From the binding energy of the ESCA spectrum, the amounts of chemical shift were used to identify

Shuo-Jen Lee; Jian-Jang Lai; Ching-Han Huang

2005-01-01

245

Bipolar battery plate  

SciTech Connect

A method is described of forming a bipolar plate for a battery comprising the steps of: disposing metal pellets in each aperture of a perforated thermoplastic sheet to form an assembly; heating and pressing the assembly to seal the pellets into the apertures with first and second surfaces exposed in the opposite faces of the sheet.

Rowlette, J.J.

1987-04-21

246

Design, Simulation and Modeling of Insulated Gate Bipolar Transistor  

E-print Network

of IGBT circuits based on device simulation and combinatorial optimization. Our method leads to the optimal IGBT layout consisting of hexagons, which is 6 % more efficient in terms of performance (current per unit area) over that of squares, and up to 80...

Gupta, Kaustubh

2013-07-09

247

InP heterojunction bipolar transistor decision circuits  

Microsoft Academic Search

We have designed and built 30 Gb\\/s master-slave D-flip-flop circuits using InGaAs-InAlAs HBT's. The HBT devices have a ? of 30, and fmax and f, of 160 and 106 GHz, respectively. We discuss methods of testing decision circuits when bit error rate testing is not available at high data rates

L. Samoska; R. Pullela; B. Agarwal; D. Mensa; Q. Lee; V. Kaman; J. Guthrie; M. J. Rodwell

1998-01-01

248

Bipolar patients with seasonal pattern 1 BIPOLAR DISORDER WITH SEASONAL PATTERN  

E-print Network

Bipolar patients with seasonal pattern 1 BIPOLAR DISORDER WITH SEASONAL PATTERN: CLINICAL patients with seasonal pattern 2 ABSTRACT Bipolar disorder (BD) has a multifactorial etiology of disorder. KEYWORDS: bipolar disorder, seasonality, seaso

Boyer, Edmond

249

Polyphosphonium-based bipolar membranes for rectification of ionic currents.  

PubMed

Bipolar membranes (BMs) have interesting applications within the field of bioelectronics, as they may be used to create non-linear ionic components (e.g., ion diodes and transistors), thereby extending the functionality of, otherwise linear, electrophoretic drug delivery devices. However, BM based diodes suffer from a number of limitations, such as narrow voltage operation range and/or high hysteresis. In this work, we circumvent these problems by using a novel polyphosphonium-based BM, which is shown to exhibit improved diode characteristics. We believe that this new type of BM diode will be useful for creating complex addressable ionic circuits for delivery of charged biomolecules. PMID:24400035

Gabrielsson, Erik O; Berggren, Magnus

2013-01-01

250

Microstructure characterization of Cu,Ge/n-type GaAs ohmic contacts M. 0. Aboelfotoh, S. Oktyabrsky, and J. Narayan  

E-print Network

to the Ge/Pd contacts,' and that n-channel GaAs metal- semiconductor field-effect transistors using the q of the heterostructure we deduce the optimum concentration of Ge to be 30 at. % for formation of low-resistance ohmic

Woodall, Jerry M.

251

Materials Science and Engineering, B3 (1989) 273-277 273 Ion-beam-induced Intermixing of WSio.45and GaAs  

E-print Network

height [1]. The most common gate metallization for GaAs field effect transistors (FETs) is WSix, which of disorder near the metal-semiconductor interface, which is not repaired by annealing. This damage consists contacts commonly used in device applications generally exhibit a rather restricted range of Schottky

Florida, University of

252

n-Type Doping of Vapor-Liquid-Solid Grown GaAs Nanowires  

NASA Astrophysics Data System (ADS)

In this letter, n-type doping of GaAs nanowires grown by metal-organic vapor phase epitaxy in the vapor-liquid-solid growth mode on (111)B GaAs substrates is reported. A low growth temperature of 400°C is adjusted in order to exclude shell growth. The impact of doping precursors on the morphology of GaAs nanowires was investigated. Tetraethyl tin as doping precursor enables heavily n-type doped GaAs nanowires in a relatively small process window while no doping effect could be found for ditertiarybutylsilane. Electrical measurements carried out on single nanowires reveal an axially non-uniform doping profile. Within a number of wires from the same run, the donor concentrations N D of GaAs nanowires are found to vary from 7 × 1017 cm-3 to 2 × 1018 cm-3. The n-type conductivity is proven by the transfer characteristics of fabricated nanowire metal-insulator-semiconductor field-effect transistor devices.

Gutsche, Christoph; Lysov, Andrey; Regolin, Ingo; Blekker, Kai; Prost, Werner; Tegude, Franz-Josef

2011-12-01

253

Pleated metal bipolar assembly  

DOEpatents

A thin low-cost bipolar plate for an electrochemical cell is formed from a polymer support plate with first flow channels on a first side of the support plate and second flow channels on a second side of the support plate, where the first flow channels and second flow channels have intersecting locations and have a depth effective to form openings through the support plate at the intersecting locations. A first foil of electrically conductive material is pressed into the first flow channels. A second foil of electrically conductive material pressed into the second flow channels so that electrical contact is made between the first and second foils at the openings through the support plate. A particular application of the bipolar plate is in polymer electrolyte fuel cells.

Wilson, Mahlon S. (Los Alamos, NM); Zawodzinski, Christine (Los Alamos, NM)

2001-01-01

254

Bipolar Disorder in Children and Teens  

MedlinePLUS

... How is bipolar disorder different in children and teens than it is in adults? When children develop ... Think about death or suicide. Do children and teens with bipolar disorder have other problems? Bipolar disorder ...

255

Update on pediatric bipolar disorder  

Microsoft Academic Search

Children and adolescents with a bipolar disorder experience mood dysregulation that is often chronic with little interepisodic\\u000a recovery. Although bipolar disorder in youth is recognized by more and more clinicians, much is still not known regarding\\u000a how best to accurately diagnose and effectively treat it. As a result, children and adolescents with bipolar disorder are\\u000a often symptomatic for long periods

Lisa D. Townsend; Christine A. Demeter; Michael Wilson; Robert L. Findling

2007-01-01

256

Reduced-dimension transistors: Reduced-dimension transistors  

E-print Network

1 Reduced-dimension transistors: the HEMT LECTURE 20 · Reduced-dimension transistors · HEMT · 2-D;2 Examples of 3-, 2- and 1-D transistors #12;3 High electron-mobility Transistor · Note the Schottky barrier

Pulfrey, David L.

257

Total Dose Effects on Single Event Transients in Digital CMOS and Linear Bipolar Circuits  

NASA Technical Reports Server (NTRS)

This presentation discusses the effects of ionizing radiation on single event transients (SETs) in circuits. The exposure of integrated circuits to ionizing radiation changes electrical parameters. The total ionizing dose effect is observed in both complementary metal-oxide-semiconductor (CMOS) and bipolar circuits. In bipolar circuits, transistors exhibit grain degradation, while in CMOS circuits, transistors exhibit threshold voltage shifts. Changes in electrical parameters can cause changes in single event upset(SEU)/SET rates. Depending on the effect, the rates may increase or decrease. Therefore, measures taken for SEU/SET mitigation might work at the beginning of a mission but not at the end following TID exposure. The effect of TID on SET rates should be considered if SETs cannot be tolerated.

Buchner, S.; McMorrow, D.; Sibley, M.; Eaton, P.; Mavis, D.; Dusseau, L.; Roche, N. J-H.; Bernard, M.

2009-01-01

258

Monolithic integration of a GaAlAs buried-heterostructure laser and a bipolar phototransistor  

NASA Technical Reports Server (NTRS)

A GaAlAs buried-heterostructure laser has been monolithically integrated with a bipolar phototransistor. The heterojunction transistor was formed by the regrowth of the burying layers of the laser. Typical threshold current values for the lasers were 30 mA. Common-emitter current gains for the phototransistor of 100-400 and light responsitivity of 75 A/W (for wavelengths of 0.82 micron) at collector current levels of 15 mA were obtained.

Bar-Chaim, N.; Harder, CH.; Margalit, S.; Yariv, A.; Katz, J.; Ury, I.

1982-01-01

259

An ultrawideband spin-wave medium-power chaos generator based on field-effect transistors  

NASA Astrophysics Data System (ADS)

A prototype of an ultrawideband (UWB) microwave chaos generator based on a nonlinear spin-wave transmission line, a multistage transistor amplifier with an output amplifier based on GaAs field-effect transistors, and a microstrip bandpass filter was constructed. The possibility of autonomous generation of a UWB chaotic microwave signal with a central frequency of 3 GHz and a total power of about 4 W in a frequency band exceeding 30% was demonstrated. The proposed chaos generator is characterized by a fairly high efficiency of about 20%.

Grishin, S. V.; Grishin, V. S.; Romanenko, D. V.; Sharaevskii, Yu. P.

2014-10-01

260

Bipolar disorder: the neglected psychosis  

Microsoft Academic Search

Bipolar disorder is a serious chronic illness which is ranked sixth among all medical disorders in years of life lost to death or disability. While abnormalities of monoaminergic neurotransmitter systems have been observed in the illness, various intracellular signalling pathways, which are potential substrates of lithium and valproate, are also implicated in the pathophysiology of bipolar disorder. The illness is

Zubin Bhagwagar; Guy M Goodwin

2004-01-01

261

Staying well with bipolar disorder  

Microsoft Academic Search

Objective: The research aimed to investigate how people diagnosed with bipolar mood disorder avoided episodes of illness and managed to stay well. The research also examined the role that personal, social and environmental factors played in helping people with bipolar mood disorder to stay well. Method: This project used a combination of qualitative research methods. The design contained three (3)

Sarah J. Russell; Jan L. Browne

2005-01-01

262

Fracture mechanics evaluation of GaAs  

NASA Technical Reports Server (NTRS)

A data base of mechanical and fracture properties for GaAs was generated. The data for single crystal GaAs will be used to design reusable GaAs solar modules. Database information includes; (1) physical property characterizations; (2) fracture behavior evaluations; and (3) strength of cells determined as a function of cell processing and material parameters.

Chen, C. P.

1984-01-01

263

Kleine-Levin syndrome and bipolar disorder Kleine-Levin syndrome and bipolar disorder  

E-print Network

Kleine-Levin syndrome and bipolar disorder Kleine-Levin syndrome and bipolar disorder in "Bipolar Disorders 2013;15(8):899-902" DOI : 10.1111/bdi.12119 #12;Kleine-Levin syndrome and bipolar. Methods: We report the case of a 44-year-old Caucasian woman with bipolar disorder (BD) subtype I referred

264

Bipolar pulse forming line  

DOEpatents

A bipolar pulse forming transmission line module for linear induction accelerators having first, second, third, fourth, and fifth planar conductors which form an interleaved stack with dielectric layers between the conductors. Each conductor has a first end, and a second end adjacent an acceleration axis. The first and second planar conductors are connected to each other at the second ends, the fourth and fifth planar conductors are connected to each other at the second ends, and the first and fifth planar conductors are connected to each other at the first ends via a shorting plate adjacent the first ends. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short a high voltage from the first end of the third planar conductor to the first end of the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

Rhodes, Mark A. (Pleasanton, CA)

2008-10-21

265

Microwave operation of GaN\\/AlGaN-doped channel heterostructure field effect transistors  

Microsoft Academic Search

We report on the microwave operation of 1 ?m gate AlGaN\\/GaN doped channel heterostructure field effect transistors (DC-HFET's) with the cutoff frequency fT of 18.3 GHz. These devices exhibit the cutoff frequency-gate length product in excess of 18 GHz·?m, comparable to that of the state-of-the-art GaAs MESFET's. We explain these improvements in the device performance by the increased sheet carrier

M. Asif Khan; Q. Chen; J. W. Yang; Michael S. Shur; B. T. Dermott; J. A. Higgins

1996-01-01

266

HCI and NBTI induced degradation in gate-all-around silicon nanowire transistors  

Microsoft Academic Search

The silicon nanowire transistor (SNWT) with gate-all-around (GAA) structure can be considered as one of the potential candidates for ultimate scaling due to its superior gate control capability and improved carrier transportation property. In this paper, hot carrier injection (HCI) and negative bias temperature instability (NBTI) behavior of n-type and p-type SNWTs with top-down approach is discussed. In addition to

Ru Huang; Runsheng Wang; Changze Liu; Liangliang Zhang; Jing Zhuge; Yu Tao; Jibin Zou; Yuchao Liu; Yangyuan Wang

2011-01-01

267

Bipolar Disorder Among Children Overall Prevalence  

E-print Network

Bipolar Disorder Among Children Overall Prevalence · Bipolar Disorder usually starts in late adolescence or early adulthood, but children can have bipolar disorder too. · Community studies estimate are complex. Different kinds of psychotherapy can also help children with bipolar disorder

Baker, Chris I.

268

Neuropsychological performance in pediatric bipolar disorder  

Microsoft Academic Search

BackgroundGrowing awareness of childhood bipolar disorder necessitates further cognitive neuroscience research to determine unique developmental differences between pediatric and adult onset bipolar disorder. We sought to examine whether neuropsychological function in children with bipolar disorder resembles that in adults with the illness and to extend our knowledge about cognitive function in pediatric bipolar disorder.

Daniel P Dickstein; Julia E Treland; Joseph Snow; Erin B McClure; Mona S Mehta; Kenneth E Towbin; Daniel S Pine; Ellen Leibenluft

2004-01-01

269

Comparison of GaAs JFETs to MESFETs for high-temperature operation  

SciTech Connect

GaAs-based Metal Semiconductor Field Effect transistors (MESFETs) and High Electron Mobility Transistors (HEMTs) have been the focus of research for high-temperature operation due to the 1.42 eV band gap of GaAs that reduces thermal carrier generation as compared to 1.1 eV silicon-based electronics. Although schemes have been proposed to minimize substrate currents at elevated temperatures, high-temperature operation of these devices is ultimately limited by the gate leakage current of the Schottky gate contact. Since a Junction Field Effect Transistor (JFET) has a higher gate barrier to current flow than a Schottky barrier MESFET as a result of the p/n junction gate, JFETs should have superior performance at elevated temperatures. This paper compares the high-temperature performance of a self-aligned GaAs MESFET and JFET. Both devices suffer from substrate leakage at high temperature; however, the JFET has superior gate characteristics and maintains a larger fraction of its room temperature transconductance at 300 C.

Zolper, J.C.; Hietala, V.M.; Housel, M.S.; Baca, A.G. [Sandia National Labs., Albuquerque, NM (United States); Sherwin, M.E. [Microwave Signal, Inc., Clarksburg, MD (United States)

1996-06-01

270

An analytical model for square GAA MOSFETs including quantum effects  

NASA Astrophysics Data System (ADS)

In this paper we introduce an analytical model for square Gate-All-Around (GAA) MOSFETs including quantum effects. With the model developed, it is possible to provide an analytical description of the 2D inversion charge distribution function (ICDF) in square GAA MOSFETs of different sizes and for all the operational regimes. The accuracy of the model is verified by comparing the data with that obtained by means of a 2D numerical simulator that self-consistently solves the Poisson and Schrödinger equations. The expressions presented here are useful to achieve a good description of the physics of these transistors; in particular, of the quantization effects on the inversion charge. The analytical ICDF obtained is used to calculate important parameters from the device compact modeling viewpoint, such as the inversion charge centroid and the gate-to-channel capacitance, which are modeled for different device geometries and biases. The model presented accurately reproduces the simulation results for the devices under study and for different operational regimes.

Moreno, E.; Roldán, J. B.; Ruiz, F. G.; Barrera, D.; Godoy, A.; Gámiz, F.

2010-11-01

271

Comorbid anxiety in bipolar disorder  

PubMed Central

Objective Comorbid anxiety disorder is reported to increase suicidality in bipolar disorder. However, studies of the impact of anxiety disorders on suicidal behavior in mood disorders have shown mixed results. The presence of personality disorders, often comorbid with anxiety and bipolar disorders, may explain these inconsistencies. This study examined the impact of comorbid Cluster B personality disorder and anxiety disorder on suicidality in bipolar disorder. Methods A total of 116 depressed bipolar patients with and without lifetime anxiety disorder were compared. Multiple regression analysis tested the association of comorbid anxiety disorder with past suicide attempts and severity of suicidal ideation, adjusting for the effect of Cluster B personality disorder. The specific effect of panic disorder was also explored. Results Bipolar patients with and without anxiety disorders did not differ in the rate of past suicide attempt. Suicidal ideation was less severe in those with anxiety disorders. In multiple regression analysis, anxiety disorder was not associated with past suicide attempts or with the severity of suicidal ideation, whereas Cluster B personality disorder was associated with both. The results were comparable when comorbid panic disorder was examined. Conclusions Comorbid Cluster B personality disorder appears to exert a stronger influence on suicidality than comorbid anxiety disorder in persons with bipolar disorder. Assessment of suicide risk in patients with bipolar disorder should include evaluation and treatment of Cluster B psychopathology. PMID:18452449

Nakagawa, Atsuo; Grunebaum, Michael F; Sullivan, Gregory M; Currier, Dianne; Ellis, Steven P; Burke, Ainsley K; Brent, David A; Mann, J John; Oquendo, Maria A

2009-01-01

272

Advances in photoreflectance characterisation of photonic (resonant-cavity) and transistor epiwafers  

NASA Astrophysics Data System (ADS)

Advances in the application of non-contact photoreflectance (PR) spectroscopy to the characterisation of epiwafer device materials are presented. The study examines both vertical cavity surface emitting laser (VCSEL) and heterojunction bipolar transistor (HBTs) device structures. Emphasis is placed on the technologically important applications of VCSEL device material characterisation, for which PR offers the only true non-destructive testing capability, as well as upon the measurement of electric fields in device epiwafers for rf application transistors such as HBTs. This paper demonstrates the application of non-destructive and rapid techniques for evaluation and control of compound semiconductor materials for both VCSEL and HBT technology.

Murtagh, M. E.; Ward, S.; Kelly, P. V.

2005-03-01

273

Transistor-based interface circuitry  

DOEpatents

Among the embodiments of the present invention is an apparatus that includes a transistor, a servo device, and a current source. The servo device is operable to provide a common base mode of operation of the transistor by maintaining an approximately constant voltage level at the transistor base. The current source is operable to provide a bias current to the transistor. A first device provides an input signal to an electrical node positioned between the emitter of the transistor and the current source. A second device receives an output signal from the collector of the transistor.

Taubman, Matthew S. (Richland, WA)

2007-02-13

274

Transistor-based interface circuitry  

DOEpatents

Among the embodiments of the present invention is an apparatus that includes a transistor, a servo device, and a current source. The servo device is operable to provide a common base mode of operation of the transistor by maintaining an approximately constant voltage level at the transistor base. The current source is operable to provide a bias current to the transistor. A first device provides an input signal to an electrical node positioned between the emitter of the transistor and the current source. A second device receives an output signal from the collector of the transistor.

Taubman, Matthew S. (Richland, WA)

2004-02-24

275

Preventing Simultaneous Conduction In Switching Transistors  

NASA Technical Reports Server (NTRS)

High voltage spikes and electromagnetic interference suppressed. Power-supply circuit including two switching transistors easily modified to prevent simultaneous conduction by both transistors during switching intervals. Diode connected between collector of each transistor and driving circuit for opposite transistor suppresses driving signal to transistor being turned on until transistor being turned off ceases to carry current.

Mclyman, William T.

1990-01-01

276

[Revisiting bipolar disorder].  

PubMed

According to the theory of evolution of Charles Darwin which is an author of The Origin of Species, human being evolves after long time to be profitable to "prosperity of a kind", and it is thought that there is the adaptive meaning. In other words, man stand on various creatures in number, and it may be said that human being building a high civilized society is the creature which was able to have an element of chosen mind and body in natural selection. However, a disease does not disappear from our daily life and tends to consider us to be "the misfortune" even if we human being is easy to suffer from a disease. "Evolution medicine" (Darwinian medicine) drop hint of meaning/the significance in aging and the process of the pathology. This paper refers to such a conception of bipolar disorder. PMID:17877000

Senjyu, Yoshika; Ozawa, Hiroki

2007-09-01

277

Growth and properties of crystalline barium oxide on the GaAs(100) substrate  

SciTech Connect

Growing a crystalline oxide film on III-V semiconductor renders possible approaches to improve operation of electronics and optoelectronics heterostructures such as oxide/semiconductor junctions for transistors and window layers for solar cells. We demonstrate the growth of crystalline barium oxide (BaO) on GaAs(100) at low temperatures, even down to room temperature. Photoluminescence (PL) measurements reveal that the amount of interface defects is reduced for BaO/GaAs, compared to Al{sub 2}O{sub 3}/GaAs, suggesting that BaO is a useful buffer layer to passivate the surface of the III-V device material. PL and photoemission data show that the produced junction tolerates the post heating around 600?°C.

Yasir, M.; Dahl, J.; Lång, J.; Tuominen, M.; Punkkinen, M. P. J.; Laukkanen, P., E-mail: pekka.laukkanen@utu.fi; Kokko, K. [Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland)] [Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Kuzmin, M. [Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland) [Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Ioffe Physical-Technical Institute, Russian Academy of Sciences, St. Petersburg 194021 (Russian Federation); Korpijärvi, V.-M.; Polojärvi, V.; Guina, M. [Optoelectronics Research Centre, Tampere University of Technology, FI-33101 Tampere (Finland)] [Optoelectronics Research Centre, Tampere University of Technology, FI-33101 Tampere (Finland)

2013-11-04

278

The history of bipolar disorders  

Microsoft Academic Search

Bipolar disorders have a long history. Depression and mania are mankind’s oldest known mental disorders, and they were the\\u000a first mental disorders conceptualised by Hippocrates as a part of medicine. Mania and depression as part of one and the same\\u000a disease—what we today call bipolar disorder—was first described by the famous Greek physician of the first century AD, Aretaeus\\u000a of

Andreas Marneros

279

Characterization of current-induced degradation in Be-doped HBTs based in GaAs and InP  

Microsoft Academic Search

The changes in the device characteristics under high-bias conditions are investigated for InAlAs\\/InGaAs and AlGaAs\\/GaAs heterojunction bipolar transistors (HBTs) with heavily Be-doped base lasers, focusing on the base current and 1\\/f noise characteristics. It is shown that the ideality factor of the surface recombination base current provides information on the Be movement accompanying the degradation. For stress current densities up

Shin-ichi Tanaka; Hidenori Shimawaki; Kensuke Kasahara; Kazuhiko Honjo

1993-01-01

280

Boron nitride housing cools transistors  

NASA Technical Reports Server (NTRS)

Boron nitride ceramic heat sink cools transistors in r-f transmitter and receiver circuits. Heat dissipated by the transistor is conducted by the boron nitride housing to the metal chassis on which it is mounted.

1965-01-01

281

Threat sensitivity in bipolar disorder.  

PubMed

Life stress is a major predictor of the course of bipolar disorder. Few studies have used laboratory paradigms to examine stress reactivity in bipolar disorder, and none have assessed autonomic reactivity to laboratory stressors. In the present investigation we sought to address this gap in the literature. Participants, 27 diagnosed with bipolar I disorder and 24 controls with no history of mood disorder, were asked to complete a complex working memory task presented as "a test of general intelligence." Self-reported emotions were assessed at baseline and after participants were given task instructions; autonomic physiology was assessed at baseline and continuously during the stressor task. Compared to controls, individuals with bipolar disorder reported greater increases in pretask anxiety from baseline and showed greater cardiovascular threat reactivity during the task. Group differences in cardiovascular threat reactivity were significantly correlated with comorbid anxiety in the bipolar group. Our results suggest that a multimethod approach to assessing stress reactivity-including the use of physiological parameters that differentiate between maladaptive and adaptive profiles of stress responding-can yield valuable information regarding stress sensitivity and its associations with negative affectivity in bipolar disorder. (PsycINFO Database Record (c) 2015 APA, all rights reserved). PMID:25688436

Muhtadie, Luma; Johnson, Sheri L

2015-02-01

282

K-band receiver front-ends in a GaAs metamorphic HEMT process  

Microsoft Academic Search

In this paper, we present K-band receiver blocks fabricated in a state-of-the-art 0.18-?m GaAs metamorphic high electron-mobility transistor (MHEMT) process using a 60% indium-content InGaAs channel. Several circuits are developed to demonstrate the superior noise performance and successful integration of K-band receiver components in such a process. We show a low-power three-stage low-noise amplifier (LNA) with a gain of 23

Babak Matinpour; Neeraj Lal; Joy Laskar; Robert E. Leoni; Colin S. Whelan

2001-01-01

283

Safe operating area of AlGaAs\\/InGaAs\\/GaAs HEMT power transistors  

Microsoft Academic Search

A study of the physical phenomena leading to second breakdown of AlGaAs\\/InGaAs\\/GaAs power HEMTs in high voltage and high current conditions is presented. The boundary of the safe operating area (SOA) is measured in both DC and pulsed conditions. The effect of gate de-biasing and triggering of the parasitic bipolar transistor are identified as reasons for deterioration of the SOA.

Vipindas Pala; Mona Hella; T. Paul Chow

2011-01-01

284

ORIGINAL PAPER Olfactory identification and preference in bipolar disorder  

E-print Network

ORIGINAL PAPER Olfactory identification and preference in bipolar disorder and schizophrenia Amanda and olfactory preference in schizophrenia and bipolar disorder. Individuals with schizophrenia or bipolar in bipolar disorder. Social competence was associated with better olfactory identification performance

Palmeri, Thomas

285

Development of a HgCdTe photomixer and impedance matched GaAs FET amplifier  

NASA Technical Reports Server (NTRS)

A research program for the development of a 10.6 micron HgCdTe photodiode/GaAs field effect transistor amplifier package for use at cryogenic temperatures (77k). The photodiode/amplifier module achieved a noise equivalent power per unit bandwidth of 5.7 times 10 to the 20th power W/Hz at 2.0 GHz. The heterodyne sensitivity of the HgCdTe photodiode was improved by designing and building a low noise GaAs field effect transistor amplifier operating at 77K. The Johnson noise of the amplifier was reduced at 77K, and thus resulted in an increased photodiode heterodyne sensitivity.

Shanley, J. F.; Paulauskas, W. A.; Taylor, D. R.

1982-01-01

286

CARBON NANOTUBE TRANSISTORS: AN EVALUATION  

E-print Network

CARBON NANOTUBE TRANSISTORS: AN EVALUATION L.C. Castro, D.L. John, and D.L. Pulfrey Department-effect transistors. It is shown that, by appropriate work function engineering of the source, drain and gate contacts-effect transistors, nanotechnology 1. INTRODUCTION Carbon nanotube molecules can be either metallic or semiconducting

Pulfrey, David L.

287

[Unipolar versus bipolar depression: clues toward predicting bipolarity disorder].  

PubMed

Bipolar and unipolar disorders share a common depressive clinical manifestation. It is important to distinguish between these two forms of depression for several reasons. First, prescribing antidepressors in monotherapy indubitably worsens the prognosis of bipolarity disorders. Second, postponing the prescription of a mood stabilizer reduces the efficacy of the treatment and multiplies the suicidal risks by two. The object of this study is to reveal the factors that distinguish between unipolar and bipolar depression. This is a retrospective study on patients' files. It includes 186 patients divided according to DSM IV criteria into two groups: patients with bipolar disorder type I or II with a recent depressive episode (123 patients) and patients with recurrent depressive disorder (63 patients). A medical record card was filled-in for every patient. It included socio-demographic data, information about the disorder, family antecedents, CGI score (global clinical impressions), physical comorbidity, substance abuse and personality disorder. In order to sort out the categorization variables, the two groups were compared using chi2 test or Fischer's test. With regard to the quantitative variables, the two groups were compared using Krostal Wallis's test or Ancova. Our study has revealed that bipolar disorder differs significantly from unipolar disorder in the following respects: bipolar disorder is prevalent among men (sex-ratio 2) while unipolar disorder is prevailing among women (sex-ratio 0.8); patients with bipolar disorder are younger than patients with unipolar disorder (38.1 +/- 5 years vs. 49.7 +/- years); the age at the onset of bipolar disorder is earlier than that of unipolar disorder (20.8 +/- 2 years vs. 38.7 +/- 5 years); family antecedents are more important in bipolar patients than in unipolar patients (51.1% vs. 33%). More importantly, bipolar disorder differs from unipolar disorder in the following aspects: The number of suicidal attempts (25.3% vs. 23.6%); the degree of substance abuse (15.4% vs. 14.5%); the level of somatic comorbidity (20.3% vs. 17.4%); the amount of anxiety manifestations (5.6% vs. 4.8%); the extent of personality disorder (30.8% vs. 23.8%); the degree of socio-professional impairment (bachelorhood and unemployment). On the other hand, we noted that unipolar patients differ from bipolar patients in terms of the frequency of hospitalizations (3.5 vs. 3.1) and the length of stays in hospitals (25.8 vs. 20.7 days) with significant differences of 0.003 and 0.0000001 respectively. Moreover, the CGI scores of unipolar patients are higher than those of bipolar patients. However, the difference is not significant. Consequently, an early distinction between bipolar and unipolar disorder is of utmost importance for the treatment of these two illnesses. PMID:17372540

Ben Abla, T; Ellouze, F; Amri, H; Krid, G; Zouari, A; M'Rad, M F

2006-01-01

288

Bipolarity and the relational division Nouredine Tamani1  

E-print Network

then a bipolar query as a query that involves bipolar conditions. This paper is set in the general case of fuzzy/ENSSAT/Univ. Rennes 1, rocacher@enssat.fr Abstract A fuzzy bipolar relation is a relation defined by a fuzzy bipolar, several forms of bipolar division when the involved relations are defined by fuzzy bipolar conditions

Boyer, Edmond

289

Treatment of bipolar disorder  

PubMed Central

We review recent developments in the acute and long-term treatment of bipolar disorder and identify promising future routes to therapeutic innovation. Overall, advances in drug treatment remain quite modest. Antipsychotic drugs are effective in the acute treatment of mania; their efficacy in the treatment of depression is variable with the clearest evidence for quetiapine. Despite their widespread use, considerable uncertainty and controversy remains about the use of antidepressant drugs in the management of depressive episodes. Lithium has the strongest evidence for long-term relapse prevention; the evidence for anticonvulsants such as divalproex and lamotrigine is less robust and there is much uncertainty about the longer term benefits of antipsychotics. Substantial progress has been made in the development and assessment of adjunctive psychosocial interventions. Long-term maintenance and possibly acute stabilisation of depression can be enhanced by the combination of psychosocial treatments with drugs. The development of future treatments should consider both the neurobiological and psychosocial mechanisms underlying the disorder. We should continue to repurpose treatments and to recognise the role of serendipity. We should also investigate optimum combinations of pharmacological and psychotherapeutic treatments at different stages of the illness. Clarification of the mechanisms by which different treatments affect sleep and circadian rhythms and their relation with daily mood fluctuations is likely to help with the treatment selection for individual patients. To be economically viable, existing psychotherapy protocols need to be made briefer and more efficient for improved scalability and sustainability in widespread implementation. PMID:23663953

2013-01-01

290

Stainless steel bipolar plates  

NASA Astrophysics Data System (ADS)

In this research, a specific surface modification technology was developed for stainless steel bipolar plates to obtain a corrosion-resistant oxide film. The surface roughness was measured, and an electron spectroscopy analysis (ESCA) was conducted to verify the chemical composition of the surface layer. From the binding energy of the ESCA spectrum, the amounts of chemical shift were used to identify the major chemical compositions. The thickness of the oxide film was analyzed by auger electron spectroscopy (AES). From the results of the ESCA and AES analyses, the effects of the surface modification on the integrity of the surface were evaluated. Uniform corrosion and localized corrosion tests were also conducted to investigate any improvement on the corrosion characteristics. A single cell was assembled for cell performance tests. The surface of the treated plates was bright and smooth. The ESCA and AES analyses showed that the treated plates had a much higher chrome content. The metallurgical structure was dense with substantially less defects. The chemical and electrochemical properties were more stable. The corrosion rates of the treated plates were also much improved, resulting in better electric conductivity, stable cell performance as well as longer cell life.

Lee, Shuo-Jen; Lai, Jian-Jang; Huang, Ching-Han

291

Early onset bipolar disorder Early Onset Bipolar Disorder: validation from admixture analyses and biomarkers.  

E-print Network

Early onset bipolar disorder 1 Early Onset Bipolar Disorder: validation from admixture analyses of Psychiatry / Revue Canadienene de Psychiatrie 2013;58(4):240-248" #12;Early onset bipolar disorder 2 Abstract-11Apr2013 #12;Early onset bipolar disorder 3 Résumé français : Objectifs : Le Trouble Bipolaire (TB) est

Paris-Sud XI, Université de

292

Hippocampal interneurons in bipolar disorder  

PubMed Central

Context Postmortem studies have reported decreased density and decreased gene expression of hippocampal interneurons in bipolar disorder, but neuroimaging studies of hippocampal volume and function have been inconclusive. Objective To assess hippocampal volume, neuron number and interneurons in the same specimens of bipolar and healthy control subjects. Design Whole human hippocampi of 14 bipolar and 18 healthy control subjects were cut at 2.5 mm intervals and sections from each tissue block were either Nissl-stained or stained with antibodies against somatostatin or parvalbumin. Messenger RNA was extracted from fixed tissue and real-time quantitative PCR was performed. Setting Basic research laboratories at Vanderbilt University and McLean Hospital. Samples Brain specimens from the Harvard Brain Tissue Resource Center at McLean Hospital. Main Outcome Measures Volume of pyramidal and non-pyramidal cell layers, overall neuron number and size, number of somatostatin- and parvalbumin-positive interneurons and messenger RNA levels of somatostatin, parvalbumin and glutamic acid decarboxylase 1. Results The two groups did not differ in the total number of hippocampal neurons, but the bipolar disorder group showed reduced volume of the non-pyramidal cell layers, reduced somal volume in cornu ammonis sector 2/3, reduced number of somatostatin and parvalbumin-positive neurons, and reduced messenger RNA levels for somatostatin, parvalbumin and glutamate decarboxylase 1. Conclusions Our results indicate a specific alteration of hippocampal interneurons in bipolar disorder, likely resulting in hippocampal dysfunction. PMID:21135314

Konradi, Christine; Zimmerman, Eric I.; Yang, C. Kevin; Lohmann, Kathryn M.; Gresch, Paul; Pantazopoulos, Harry; Berretta, Sabina; Heckers, Stephan

2011-01-01

293

Treatments in child and adolescent bipolar disorders  

Microsoft Academic Search

The existence of bipolar disorder in adolescents is now clearly established. However, whether bipolarity exists in children\\u000a is more controversial. We reviewed the literature on acute and prophylactic treatment of bipolar disorder in youths. The guidelines\\u000a for the treatment of bipolar disorder in children and adolescents are generally similar to those applied in adult practice.\\u000a But no evidence-based data support

Angèle Consoli; Emmannuelle Deniau; Christophe Huynh; Diane Purper; David Cohen

2007-01-01

294

Radiation damage testing of transistors for SSC front-end electronics  

SciTech Connect

Over the ten year expected lifetime of a typical SSC detector operating at the design luminosity of 10{sup 33} cm{sup {minus}2}s{sup {minus}1}, the front-end electronics at large pseudorapidities may receive total doses as high as 20 MRad(Si) of ionizing radiation and 10{sup 16} neutrons/cm{sup 2}. Discrete JFETs and monolithic MOS and bipolar transistors have been irradiated at 10 MRad(Si) and 10{sup 14} neutrons/cm{sup 2}, and the effect on transfer characteristics and noise performance have been measured. All transistors were still functional after irradiation but suffered increased noise and the MOS transistors showed significant threshold shifts and increased leakage currents. 4 refs., 2 figs.

Dawson, J.; Ekenberg, T.; Stevens, A. (Argonne National Lab., IL (USA)); Kraner, H.; Radeka, V.; Rescia, S. (Brookhaven National Lab., Upton, NY (USA)); Kerns, S. (Vanderbilt Univ., Nashville, TN (USA). Dept. of Electrical Engineering)

1990-01-01

295

Reconfigurable silicon nanowire transistors.  

PubMed

Over the past 30 years electronic applications have been dominated by complementary metal oxide semiconductor (CMOS) devices. These combine p- and n-type field effect transistors (FETs) to reduce static power consumption. However, CMOS transistors are limited to static electrical functions, i.e., electrical characteristics that cannot be changed. Here we present the concept and a demonstrator of a universal transistor that can be reversely configured as p-FET or n-FET simply by the application of an electric signal. This concept is enabled by employing an axial nanowire heterostructure (metal/intrinsic-silicon/metal) with independent gating of the Schottky junctions. In contrast to conventional FETs, charge carrier polarity and concentration are determined by selective and sensitive control of charge carrier injections at each Schottky junction, explicitly avoiding the use of dopants as shown by measurements and calculations. Besides the additional functionality, the fabricated nanoscale devices exhibit enhanced electrical characteristics, e.g., record on/off ratio of up to 1 × 10(9) for Schottky transistors. This novel nanotransistor technology makes way for a simple and compact hardware platform that can be flexibly reconfigured during operation to perform different logic computations yielding unprecedented circuit design flexibility. PMID:22111808

Heinzig, André; Slesazeck, Stefan; Kreupl, Franz; Mikolajick, Thomas; Weber, Walter M

2012-01-11

296

Photosensitive graphene transistors.  

PubMed

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. PMID:24715703

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

2014-08-20

297

Neurobiological basis of bipolar disorder Tadafumi Kato  

E-print Network

Neurobiological basis of bipolar disorder Tadafumi Kato Laboratory for Molecular Dynamics of Mental Disorders, RIKEN Brain Science Institute Bipolar disorder is characterized by recurrent episodes of mania channel genes including CACNA1C. Mendelian diseases accompanying bipolar disorder or depression include

Fukai, Tomoki

298

Metallic Bipolar Plates with Composite Coatings  

E-print Network

Metallic Bipolar Plates with Composite Coatings Jennifer Mawdsley Argonne National Laboratory Fuel Cell Projects Kickoff Meeting Washington DC October 1, 2009 #12;2 Metallic Bipolar Plates with Composite Coatings Project Objective Make aluminum-based bipolar plates an option for replacing machined

299

Transformation of bipolar fuzzy rough set models  

Microsoft Academic Search

In this paper, the notions of the union, the intersection, and the inverse of bipolar fuzzy approximation spaces are first introduced, respectively, and some related results are obtained. Then, the composition of bipolar fuzzy approximation spaces are proposed, and some properties are discussed. Finally, we give two examples to illustrate the applications of bipolar fuzzy rough set models’ transformation in

Hai-Long Yang; Sheng-Gang Li; Zhi-Lian Guo; Chun-Hui Ma

300

Equilibrium relations and bipolar fuzzy clustering  

Microsoft Academic Search

Equilibrium relations bipolar fuzzy sets are introduced. Equilibrium relations are bipolar reflexive, symmetrical, and transitive. It is proved that: (1) crisp equilibrium relations induce hard partitions of harmony sets, coalition sets, and conflict sets; and (2) fuzzy equilibrium relation induces fuzzy harmony, coalition, and conflict sets which can be either disjoint or overlapped. Conditions for disjoint bipolar fuzzy partitioning are

Wen-Ran Zhang

1999-01-01

301

Mathematical Models of Bipolar Disorder  

E-print Network

We use limit cycle oscillators to model Bipolar II disorder, which is characterized by alternating hypomanic and depressive episodes and afflicts about one percent of the United States adult population. We consider two nonlinear 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.

Darryl Daugherty; Tairi Roque-Urrea; John Urrea-Roque; Jessica Snyder; Stephen Wirkus; Mason A. Porter

2004-06-16

302

Mathematical models of bipolar disorder  

NASA Astrophysics Data System (ADS)

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.

Daugherty, Darryl; Roque-Urrea, Tairi; Urrea-Roque, John; Troyer, Jessica; Wirkus, Stephen; Porter, Mason A.

2009-07-01

303

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

PubMed Central

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

Grimmer, Yvonne; Hohmann, Sarah

2014-01-01

304

Deep level analysis in heterostructure field-effect transistors by means of the photo-FET method  

Microsoft Academic Search

The photo-FET method, a fast and simple room-temperature method for deep level analysis, was applied to heterostructure field-effect transistors for the first time. Well-known donor-like and several unknown acceptor-like levels were detected. By comparing heterostructures and homogeneously doped AlGaAs layers, GaAs- and AlGaAs-related traps could be separated. For comparison, similar samples were investigated independently by photocapacitance- and by low-frequency noise

Michael Heuken; Klaus Heime; Lutz Loreck; Klaus Ploog; Winfried Schlapp; G. Weimann

1986-01-01

305

Bipolar lead acid battery development  

NASA Technical Reports Server (NTRS)

A modular bipolar battery configuration is under development at Johnson Control, Inc. (JCI) and the Jet Propulsion Laboratory (JPL). The battery design, incorporating proven lead acid electrochemistry, yields a rechargeable, high-power source that is light weight and compact. This configuration offers advantages in power capability, weight, and volume over conventional monopolar batteries and other battery chemistries. The lead acid bipolar battery operates in a sealed, maintenance-free mode allowing for maximum application flexibility. It is ideal for high-voltage and high-power applications.

Eskra, Michael; Vidas, Robin; Miles, Ronald; Halpert, Gerald; Attia, Alan; Perrone, David

1991-01-01

306

Bipolar dislocation of the clavicle.  

PubMed

Bipolar dislocation of the clavicle at acromioclavicular and sternoclavicular joint is an uncommon traumatic injury. The conservative treatments adopted in the past is associated with redislocation dysfunction and deformity. A 41 years old lady with bipolar dislocation of right shoulder is treated surgically by open reduction and internal fixation by oblique T-plate at sternoclavicular joint and Kirschner wire stabilization at acromioclavicular joint. The patient showed satisfactory recovery with full range of motion of the right shoulder and normal muscular strength. The case reported in view of rarity and at 2 years followup. PMID:23325981

Jiang, Wei; Gao, Shu-Guang; Li, Yu-Sheng; Lei, Guang-Hua

2012-11-01

307

The bipolar spectrum: myth or reality?  

PubMed

The idea of a "bipolar spectrum" is controversial due to 1) lack of widely accepted definitions, 2) concern that spectrum definitions might subsume cases with non-bipolar disorders, 3) worry that "diagnostic creep" may lead practitioners to overdiagnose bipolar disorder in marginal cases, and 4) worry that more diagnosis of bipolar spectrum may increase aggressive pharmacotherapy. These concerns are weighed against theoretical and empiric evidence converging in support of the bipolar spectrum as having prognostic and prescriptive validity. Practitioners can use inexpensive and practical strategies to incorporate the spectrum concept into their work while minimizing risks of overdiagnosis or unnecessary medication exposure. PMID:20857347

Youngstrom, Eric; Van Meter, Anna; Algorta, Guillermo Perez

2010-12-01

308

Improved chopper circuit uses parallel transistors  

NASA Technical Reports Server (NTRS)

Parallel transistor chopper circuit operates with one transistor in the forward mode and the other in the inverse mode. By using this method, it acts as a single, symmetrical, bidirectional transistor, and reduces and stabilizes the offset voltage.

1966-01-01

309

Gyrator employing field effect transistors  

NASA Technical Reports Server (NTRS)

A gyrator circuit of the conventional configuration of two amplifiers in a circular loop, one producing zero phase shift and the other producing 180 deg phase reversal is examined. All active elements are MOS field effect transistors. Each amplifier comprises a differential amplifier configuration with current limiting transistor, followed by an output transistor in cascode configuration, and two load transistors of opposite conductivity type from the other transistors. A voltage divider control circuit comprises a series string of transistors with a central voltage input to provide control, with locations on the amplifiers receiving reference voltages by connection to appropriate points on the divider. The circuit produces excellent response and is well suited for fabrication by integrated circuits.

Hochmair, E. S. (inventor)

1973-01-01

310

Suicidality in Bipolar I Disorder  

ERIC Educational Resources Information Center

People with bipolar disorder are at high suicide risk. The literature suggests that suicidality is predicted by higher symptom severity and less use of pharmacological agents, but few studies have examined the joint contributions of these variables. The present study examines the conjoint contribution of symptom severity and pharmacological…

Johnson, Sheri L.; McMurrich, Stephanie L.; Yates, Marisa

2005-01-01

311

Corrosion resistant metallic bipolar plate  

DOEpatents

A corrosion resistant, electrically conductive component such as a bipolar plate for a PEM fuel cell includes 20 55% Cr, balance base metal such as Ni, Fe, or Co, the component having thereon a substantially external, continuous layer of chromium nitride.

Brady, Michael P. (Oak Ridge, TN); Schneibel, Joachim H. (Knoxville, TN); Pint, Bruce A. (Knoxville, TN); Maziasz, Philip J. (Oak Ridge, TN)

2007-05-01

312

Modelling bipolar multicriteria decision making  

Microsoft Academic Search

In this paper we revisit some classical multicriteria decision making aid models in order to stress the presence of dual concepts, which will be consistent with Bipolar Fuzzy Sets (sometimes called Atanassov's Intuitionistic Fuzzy Sets). In addition, we point out how such a dual approach is a non necessary binary heritage, so we can conclude how relevant in practice are

J. T. Rodriguez; B. Vitoriano; J. Montero; D. Gomez

2009-01-01

313

GaAs photovoltaics and optoelectronics using releasable multilayer epitaxial assemblies.  

PubMed

Compound semiconductors like gallium arsenide (GaAs) provide advantages over silicon for many applications, owing to their direct bandgaps and high electron mobilities. Examples range from efficient photovoltaic devices to radio-frequency electronics and most forms of optoelectronics. However, growing large, high quality wafers of these materials, and intimately integrating them on silicon or amorphous substrates (such as glass or plastic) is expensive, which restricts their use. Here we describe materials and fabrication concepts that address many of these challenges, through the use of films of GaAs or AlGaAs grown in thick, multilayer epitaxial assemblies, then separated from each other and distributed on foreign substrates by printing. This method yields large quantities of high quality semiconductor material capable of device integration in large area formats, in a manner that also allows the wafer to be reused for additional growths. We demonstrate some capabilities of this approach with three different applications: GaAs-based metal semiconductor field effect transistors and logic gates on plates of glass, near-infrared imaging devices on wafers of silicon, and photovoltaic modules on sheets of plastic. These results illustrate the implementation of compound semiconductors such as GaAs in applications whose cost structures, formats, area coverages or modes of use are incompatible with conventional growth or integration strategies. PMID:20485431

Yoon, Jongseung; Jo, Sungjin; Chun, Ik Su; Jung, Inhwa; Kim, Hoon-Sik; Meitl, Matthew; Menard, Etienne; Li, Xiuling; Coleman, James J; Paik, Ungyu; Rogers, John A

2010-05-20

314

Integrated Neurobiology of Bipolar Disorder  

PubMed Central

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 bipolarity is one of the great questions facing the field and one that is likely to have profound treatment implications, given that fact that such a discovery would greatly increase our ability to individualize – and by extension, enhance – treatment. PMID:25202283

Maletic, Vladimir; Raison, Charles

2014-01-01

315

Characterization of semiconductor device processing etchant solutions for GaAs and p+ GaAs layers employed in AlxGa(1-x)As/GaAs MODFETs and related heterojunction devices  

NASA Astrophysics Data System (ADS)

The etch rates of GaAs, p+ GaAs, Al(x)Ga(1-x)As and n-Al(x)Ga(1-x)As were examined with respect to solution composition and pH in an effort to determine a solution that will selectively etch only GaAs from the area between the gate-and-source and gate-and-drain of a p+ GaAs/Al(x)Ga(1-x)As/GaAs Modulation-Doped Field-Effect Transistor. The measurement of the etch rates for GaAs and Al(x)Ga(1-x)As was approached from different perspectives. First, a method based upon corrosion testing, that determines etch rates from weight loss, was attempted. A second method involved the use of a Fischione Twin-Jet Electropolisher. Both techniques were verified against a known method of etch depth measurement using a profilometer. A selective etch would also be useful in the last step of the fabrication process of the (ES)MODFET.

Mayhew, Brett F.

1988-11-01

316

High-frequency operation of 0.3 {mu}m GaAs JFETs for low-power electronic  

SciTech Connect

GaAs Junction Field Effect Transistors (JFETs) have attracted renewed attention for low-power, low-voltage electronics. JFETs have a significant advantage over MESFETs for low-power operation due to their higher gate barrier to current flow resulting from p/n junction gate. This paper reports recent advances in an all ion implanted self-aligned GaAs JFET with a gate length down to 0.3 {mu}m. By employing shallopw SiF implants next to the gate, dielectric sidewall spacers, and 50 keV source and drain implants, JFETs with a f{sub t} up to 49 GHz with good pinchoff and subthreshold characteristics have been realized. In addition, the JFET benefits from the use of shallow Zn or Cd implantation to form abrupt p{sup +}/n gate profiles.

Zolper, J.C.; Baca, A.G.; Hietala, V.M.; Shul, R.J. [Sandia National Labs., Albuquerque, NM (United States); Sherwin, M.E. [Microwave Signal, Clarksburg, MD (United States)

1996-09-01

317

Pulse transformer for GaAs laser  

NASA Technical Reports Server (NTRS)

High-radiance gallium arsenide (GaAs) laser operating at room temperature is utilized in optical navigation system. For efficient transformer-to-laser impedance match, laser should be connected directly to pulse transformer secondary winding.

Rutz, E. M.

1976-01-01

318

Unsplit bipolar pulse forming line  

DOEpatents

A bipolar pulse forming transmission line module and system for linear induction accelerators having first, second, third, and fourth planar conductors which form a sequentially arranged interleaved stack having opposing first and second ends, with dielectric layers between the conductors. The first and second planar conductors are connected to each other at the first end, and the first and fourth planar conductors are connected to each other at the second end via a shorting plate. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short at the first end a high voltage from the third planar conductor to the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

Rhodes, Mark A. (Pleasanton, CA)

2011-05-24

319

Depression and Bipolar Support Alliance  

NSDL National Science Digital Library

Living and coping with depression or bipolar disorder can be difficult, but there are a number of high-quality online resources that can be very useful to those with these conditions, or for those who work directly with these individuals. The homepage of the Depression and Bipolar Support Alliance (DBSA) can be of great help in this area, as their site includes everything from their "Real Recovery" podcasts to such basics as factsheets on both diseases. A good place to start here would be with any of the five primary sections, which include crisis intervention resources and recovery steps. Visitors can also view many of these materials in Spanish and they may also wish to sign up to receive the DBSA's electronic newsletter.

320

Depression and Bipolar Support Alliance  

NSDL National Science Digital Library

Living and coping with depression or bipolar disorder can be difficult, but there are a number of high-quality online resources that can be very useful to those with these conditions, or for those who work directly with these individuals. The homepage of the Depression and Bipolar Support Alliance (DBSA) can be of great help in this area, as their site includes everything from their �Real Recovery� podcasts to such basics as factsheets on both diseases. A good place to start here would be with any of the five primary sections, which include crisis intervention resources and recovery steps. Visitors can also view many of these materials in Spanish and they may also wish to sign up to receive the DBSA�s electronic newsletter.

321

Ion-implanted GaAs JFETs with f{sub t} {gt} 45 GHz for low-power electronics  

SciTech Connect

GaAs Junction Field Effect Transistors (JFETs) are reported with gate lengths down to 0.3 micrometers. The structure is fully self-aligned and employs all ion implantation doping. p[sup +]-gate regions are formed with either Zn or Cd implants along with a P coimplantation to reduce diffusion. The source and rain implants are engineered with Si or SiF implants to minimize short channel effects. JFETs with 0.3 micrometer gate length are demonstrated with a sub-threshold slope of 110 mV/decade along with an intrinsic unity current gain cutoff frequency as high as 52 GHz.

Zolper, J.C.; Baca, A.G.; Hietala, V.M.; Shul, R.J. [Sandia National Labs., Albuquerque, NM (United States); Sherwin, M.E. [Sandia National Labs., Albuquerque, NM (United States)]|[Microwave Signal, Clarksburg, MD (United States)

1996-12-31

322

Bipolar spintronics: Fundamentals and applications  

Microsoft Academic Search

By incorporating spin-dependent properties and magnetism in semiconductor structures, new applications can be considered which go beyond magnetoresistive effects in metallic systems. Notwithstanding the prospects for spin\\/magnetism-enhanced logic in semiconductors, many important theoretical, experimental, and materials challenges remain. Here we discuss the challenges for realizing a particular class of associated applications and our proposal for bipolar spintronic devices in which

Igor Zutic; Jaroslav Fabian; Steven C. Erwin

2006-01-01

323

Mutant Mouse Models of Bipolar Disorder  

Microsoft Academic Search

Bipolar disorder (also known as manic-depressive illness) is distinctive among psychiatric illnesses in that it is characterized\\u000a by spontaneously alternating episodes of depression and mania. Over the years, extensive research into the pathophysiology\\u000a of bipolar disorder has resulted in a growing understanding of the cellular, biochemical, and molecular changes associated\\u000a with bipolar disorder and its treatment. However, given its unique

Anneloes Dirks; Lucianne Groenink; Berend Olivier

324

Carbon Nanotubes as Schottky Barrier Transistors  

Microsoft Academic Search

We show that carbon nanotube transistors operate as unconventional ``Schottky barrier transistors,'' in which transistor action occurs primarily by varying the contact resistance rather than the channel conductance. Transistor characteristics are calculated for both idealized and realistic geometries, and scaling behavior is demonstrated. Our results explain a variety of experimental observations, including the quite different effects of doping and adsorbed

S. Heinze; J. Tersoff; R. Martel; V. Derycke; J. Appenzeller; Ph. Avouris

2002-01-01

325

RICE UNIVERSITY Transport in Single Molecule Transistors  

E-print Network

RICE UNIVERSITY Transport in Single Molecule Transistors by Lam H. Yu A Thesis Submitted in Partial Houston, Texas January, 2006 #12;Abstract Transport in Single Molecule Transistors by Lam H. Yu molecule transistors (SMTs), nanometer-scale transistors in which charge transport occurs through

Natelson, Douglas

326

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

ERIC Educational Resources Information Center

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…

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

327

Bipolar fuzzy cognitive mapping and bipolar visualization for OLAP\\/OLAM  

Microsoft Academic Search

Bipolar fuzzy sets and bipolar fuzzy cognitive maps (FCMs) are introduced for online analytical processing (OLAP) and online analytical mining (OLAM). As cognitive models CMs hold great potential for visualization in OLAP and OLAM. Due to the lack of formal mathematical basis, however, CM-based OLAP and OLAM have not become popular. Compared with existing approaches, bipolar fuzzy sets and CMs

Wen-Ran Zhang

2002-01-01

328

Power transistor switching characterization  

NASA Technical Reports Server (NTRS)

The switching properties of power transistors are investigated. The devices studied were housed in IO-3 cases and were of an n(+)-p-n(-)-n(+) vertical dopant structure. The effects of the magnitude of the reverse-base current and temperature on the reverse-bias second breakdown characteristics are discussed. Brief discussions of device degradation due to second breakdown and of a constant voltage turn-off circuit are included. A description of a vacuum tube voltage clamp circuit which reduces clamped collector voltage overshoot is given.

Blackburn, D. L.

1981-01-01

329

Distinctions between bipolar and unipolar depression  

PubMed Central

This is a review of the studies comparing unipolar and bipolar depression, with focus on the course, symptomatology, neurobiology, and psychosocial literatures. These are reviewed with one question in mind: does the evidence support diagnosing bipolar and unipolar depressions as the same disorder or different? The current nomenclature of bipolar and unipolar disorders has resulted in research that compares these disorders as a whole, without considering depression separately from mania within bipolar disorder. Future research should investigate two broad categories of depression and mania as separate disease processes that are highly comorbid. PMID:15792852

Cuellar, Amy K.; Johnson, Sheri L.; Winters, Ray

2010-01-01

330

Terahertz detection with field-effect-transistors via bulk plasmon-assisted self-mixing  

NASA Astrophysics Data System (ADS)

We previously reported resonant photovoltaic terahertz detection via bulk plasmons in GaAs field-effect-transistors (FETs). Here, we introduce a device model which incorporates the microscopic dynamics of terahertz-field-driven electrons in the FET channel, resonant excitation of three dimensional (bulk) plasmons, and self-mixing theory of Lisauskas and Pfeiffer. The resulting model can simulate our experimental results and implies a bulk plasmon-assisted terahertz self-mixing process occurs in the FET-based terahertz detectors. The model also suggests three factors are important to improving the device performance - power coupling efficiency, self-mixing efficiency, and resonance with bulk plasmons.

Kim, Sangwoo; Sherwin, Mark S.

2010-04-01

331

GaAs Semi-Insulating Layer for a GaAs Device  

NASA Technical Reports Server (NTRS)

Improved design for GaAs electronic device or integrated circuit designed to operate at cryogenic temperatures, customary SiO2 insulating layer replaced by semi-insulating layer of GaAs. Thermal expansions of device and covering layer therefore match closely, and thermal stresses caused by immersion in cryogenic chamber nearly eliminated.

Sherrill, G.; Mattauch, R. J.

1986-01-01

332

Current steering detection scheme of three terminal antenna-coupled terahertz field effect transistor detectors.  

PubMed

An antenna-coupled field effect transistor (FET) as a plasma wave terahertz detector is used with the current steering to record separately the gate-source and gate-drain photoresponses and their phase sensitive combination. This method is based on the observation that the plasmon-terminal coupling is cut off in saturation, resulting in only one-sided sensitivity. A polarimetric example is presented with intensity and polarization angle reconstruction using a single three-terminal antenna-coupled Si-metal-oxide semiconductor FET (MOSFET). The technique is applicable to various detection schemes and technologies (high electron mobility transistors and GaAs-, GaN-, and Si-MOSFETs), and other application possibilities are discussed. PMID:23903147

Földesy, Péter

2013-08-01

333

Field-effect tunneling transistor based on vertical graphene heterostructures.  

PubMed

An obstacle to the use of graphene as an alternative to silicon electronics has been the absence of an energy gap between its conduction and valence bands, which makes it difficult to achieve low power dissipation in the OFF state. We report a bipolar field-effect transistor that exploits the low density of states in graphene and its one-atomic-layer thickness. Our prototype devices are graphene heterostructures with atomically thin boron nitride or molybdenum disulfide acting as a vertical transport barrier. They exhibit room-temperature switching ratios of ?50 and ?10,000, respectively. Such devices have potential for high-frequency operation and large-scale integration. PMID:22300848

Britnell, L; Gorbachev, R V; Jalil, R; Belle, B D; Schedin, F; Mishchenko, A; Georgiou, T; Katsnelson, M I; Eaves, L; Morozov, S V; Peres, N M R; Leist, J; Geim, A K; Novoselov, K S; Ponomarenko, L A

2012-02-24

334

Transistor Characteristics for Direct-Coupled Transistor Logic Circuits  

Microsoft Academic Search

The basic requirement for stability of a direct-coupled transistor logic (dctl) circuit is that a voltage margin exist between the maximum collect-emitter voltage of an ``on'' unit in the system environment and the minimum base-emitter voltage required for a transistor to be sufficiently ``off.'' This margin has been expressed in terms of the fundamental device parameters: commonbase forward and inverse

James W. Easley

1958-01-01

335

Bipolar Disorder and Cognitive Therapy: A Commentary  

ERIC Educational Resources Information Center

This article comments on the three articles (Leahy, 2005; Newman, 2005; and Reilly-Harrington & Knauz, 2005) that deal with the applications of cognitive therapy to treatment of bipolar disorder. They focus on the uses of cognitive therapy in treating three important facets of the special problems of bipolar patients: rapid cycling, severe…

Riskind, John H.

2005-01-01

336

Lithium in maintenance therapy for bipolar disorder  

Microsoft Academic Search

Lithium has been used for the medical treatment of bipolar disorder for over 50 years. The purpose of this paper is to review the evidence base supporting the use of lithium in the maintenance phase of treatment of bipolar disorder and the limitations which reduce the clinical effectiveness of this medication. A selective review of the relevant literature was carried

Allan H. Young; James I. Newham

2006-01-01

337

Swimming in Deep Water: Childhood Bipolar Disorder  

ERIC Educational Resources Information Center

The authors focused on one parent's struggles in finding a diagnosis and intervention for a child who had bipolar disorder. The authors explain the process of identification, diagnosis, and intervention of a child who had bipolar disorder. In addition to the personal story, the authors provide information on the disorder and outline strategies…

Senokossoff, Gwyn W.; Stoddard, Kim

2009-01-01

338

Bipolar plates for PEM fuel cells  

Microsoft Academic Search

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

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

2003-01-01

339

GENOMIC IMPRINTING IN BIPOLAR AFFECTIVE DISORDER  

PubMed Central

With recent advances in molecular genetics, a new mechanism proposed for the inheritance of Bipolar Disorder is Genomic Imprinting or Parent of Origin Affect. In this study of 79 consecutive first episode manic patients, predominantly male, we failed to establish the phenomenon of imprinting. With other proposed non-Mendelian patterns of inheritance, it may be that bipolar disorder is genetically heterogenous. PMID:21407931

Kumar, Ratanendra; Chopra, V.K.; Parial, A.; Khess, C.R.J.

2000-01-01

340

Bipolar Disorder in School-Age Children  

ERIC Educational Resources Information Center

This article examines the individual components of bipolar disorder in children and the behaviors that can escalate as a result of misdiagnosis and treatment. The brain/behavior relationship in bipolar disorders can be affected by genetics, developmental failure, or environmental influences, which can cause an onset of dramatic mood swings and…

Olson, Patricia M.; Pacheco, Mary Rae

2005-01-01

341

Bipolar II disorder and self-identity   

E-print Network

Background: Studies on bipolar II disorder have covered a wide scope; many report the importance of a cohesive self-concept for recovery. In spite of this, there is a dearth of research explicitly investigating how bipolar II impacts one’s self...

Hannon, Julia

2012-06-27

342

Impacts of crystal orientation of GaAs on the interfacial structures and electrical properties of Hf{sub 0.6}La{sub 0.4}O{sub x} films  

SciTech Connect

One of the major challenges in realizing the GaAs channel in the metal oxide semiconductor field effect transistor is the degrading in electron transport properties at the interface between GaAs and the gate oxide. In this study, Hf{sub 0.6}La{sub 0.4}O{sub x} gate oxide films were deposited at a low temperature (200?°C) on GaAs(111)A and GaAs(100) substrates by plasma enhanced atomic layer deposition. Microstructure analysis indicates that residuals of gallium oxide, arsenic oxide, and As element remained at the interface of Hf{sub 0.6}La{sub 0.4}O{sub x}/GaAs(100). On contrast, a smoother interface is observed between Hf{sub 0.6}La{sub 0.4}O{sub x} thin film and GaAs(111)A substrate. Furthermore, a reduction of interfacial layer is observed in Hf{sub 0.6}La{sub 0.4}O{sub x}/GaAs(111)A. Electrical characterization of the metal-insulator-semiconductor Pt/Hf{sub 0.6}La{sub 0.4}O{sub x}/n-GaAs(111)A capacitor indicated a reduction of D{sub it} and leakage current compared with the capacitor fabricated on GaAs(100)

Jia, Tingting; Kimura, Hideo, E-mail: kimura.hideo@nims.go.jp [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Zhao, Hongyang [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Dingxi Road 1295, Shanghai 200050 (China); Yao, Qiwen; Cheng, Zhenxiang [Institute for Superconducting and Electronic Materials, University of Wollongong, Squires Way, North Wollongong, NSW 2500 (Australia); Cheng, Xinghong; Yu, Yuehui [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Sciences, Changning Road 865, Shanghai 200050 (China)

2014-04-07

343

High transconductance organic electrochemical transistors  

PubMed Central

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

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

344

Adiabatic Quantum Transistors  

E-print Network

We describe a many-body quantum system which can be made to quantum compute by the adiabatic application of a large applied field to the system. Prior to the application of the field quantum information is localized on one boundary of the device, and after the application of the field this information has propagated to the other side of the device with a quantum circuit applied to the information. The applied circuit depends on the many-body Hamiltonian of the material, and the computation takes place in a degenerate ground space with symmetry-protected topological order. Such adiabatic quantum transistors are universal adiabatic quantum computing devices which have the added benefit of being modular. Here we describe this model, provide arguments for why it is an efficient model of quantum computing, and examine these many-body systems in the presence of a noisy environment.

Dave Bacon; Steven T. Flammia; Gregory M. Crosswhite

2012-07-11

345

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

SciTech Connect

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&T`s CBIC-U2, 4 GHz f{sub 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 {mu}m pitch double-sided silicon strip detector. The chip measures 6.8 mm {times} 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 {Phi}=10{sup 14} protons/cm{sup 2} have been performed on the IC, demonstrating the radiation hardness of the complementary bipolar process.

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

1993-11-01

346

The prestige model of spectrum bipolarity.  

PubMed

Because affective pathogenesis is a hard problem for psychiatry, it behoves researchers to develop and test novel models of causality. We examine the notion that the adaptive drive to social investment - prestige - provides clues to the bipolar spectrum. A seven node bipolar spectrum is proposed, based on a putative gradient of "bipolarity". It is conceived that this gradient may correlate with the drive to social investment (prestige). In order to test this hypothesis with proof of concept data, a case control study categorised 228 subjects into a seven node bipolar spectrum. Whilst controlling for mood elevation and depression, differences in strategic prestige (leadership) motivation (MSPM) between spectrum groups were examined. The bipolar I (S1) node had a greater strategic prestige (leadership) motivation score than the controls (S7) by 21.17 points, 95% CI [8.16, 34.18], p<.001, d=1.05, while the bipolar II (S2) node was higher than the control group by 16.73 points, 95% CI [0.92, 32.54], p=.030, d=0.84. Whilst the pseudounipolar (S3) node (those with depression and bipolar family histories; n=17) had only a marginally statistical difference in MSPM compared to controls (p=.051), the mean difference (16.98) and d value (0.86) indicated an elevated MSPM level. Prestige (leadership) motivation score positively correlated with dimensional lifetime bipolarity (Mood Disorder Questionnaire) score (rp=0.47), supporting the spectrum prestige motivation gradient notion. Evidence is presented for a genetic disposition to elevated strategic prestige (leadership) motivation. Sensitivity to Social Inclusion (MSIS), Contingency of Self-Worth (CSW.av) and tension significantly predicted strategic prestige (leadership) motivation (MSPM) score in a multiple regression. - suggesting that a vulnerability of the social self may be a feature of bipolar disorders. The prestige model of spectrum bipolarity offers a new conceptualisation of affective disorders and has received preliminary support. PMID:25554538

Le Bas, James; Newton, Richard; Sore, Rachel; Castle, David

2015-02-01

347

Crystal growth of device quality GaAs in space  

NASA Technical Reports Server (NTRS)

The optimization of space processing of GaAs is described. The detailed compositional, structural, and electronic characterization of GaAs on a macro- and microscale and the relationships between growth parameters and the properties of GaAs are among the factors discussed. The key parameters limiting device performance are assessed.

Gatos, H. C.; Lagowski, J.

1979-01-01

348

A light emitting transistor based on a hybrid metal oxide-organic semiconductor lateral heterostructure  

NASA Astrophysics Data System (ADS)

A light-emitting field-effect transistor was fabricated, with its architecture based on a distinct heterojunction located midway between the source and drain contacts. Tetracene enabled hole transport on one side of the heterojunction (hole mobility ˜0.071 cm2/Vs), while amorphous solution-processed zinc tin oxide supported electron transport on the other side (electron mobility ˜0.81 cm2/Vs). The drain current vs. gate voltage curves of this device have a bell-shaped profile that is characteristic of lateral heterojunction bipolar field-effect transistors. The green light emission—from tetracene—closely follows the trend in drain current and is naked-eye visible in a darkened room.

Ooi, Zi-En; Foong, Thelese R. B.; Singh, Samarendra P.; Leok Chan, Khai; Dodabalapur, Ananth

2012-02-01

349

Spin-dependent quasiparticle transport in aluminum single-electron transistors.  

PubMed

We investigate the effect of Zeeman splitting on quasiparticle transport in normal-superconducting-normal (NSN) aluminum single-electron transistors (SETs). In the above-gap transport, the interplay of Coulomb blockade and Zeeman splitting leads to spin-dependence of the sequential tunneling. This creates regimes where either one or both spin species can tunnel onto or off the island. At lower biases, spin-dependence of the single quasiparticle state is studied, and operation of the device as a bipolar spin filter is suggested. PMID:17026322

Ferguson, A J; Andresen, S E; Brenner, R; Clark, R G

2006-08-25

350

Evolvable circuit with transistor-level reconfigurability  

NASA Technical Reports Server (NTRS)

An evolvable circuit includes a plurality of reconfigurable switches, a plurality of transistors within a region of the circuit, the plurality of transistors having terminals, the plurality of transistors being coupled between a power source terminal and a power sink terminal so as to be capable of admitting power between the power source terminal and the power sink terminal, the plurality of transistors being coupled so that every transistor terminal to transistor terminal coupling within the region of the circuit comprises a reconfigurable switch.

Stoica, Adrian (Inventor); Salazar-Lazaro, Carlos Harold (Inventor)

2004-01-01

351

Neurocognitive function in bipolar disorder: a comparison between bipolar I and II disorder and matched controls  

PubMed Central

Background Cognitive deficits have been documented in patients with bipolar disorder. Further, it has been suggested that the degree and type of cognitive impairment differ between bipolar I and bipolar II disorder, but data is conflicting and remains inconclusive. This study aimed to clarify the suggested differences in cognitive impairment between patients with bipolar I and II disorder in a relatively large, clinically stable sample while controlling for potential confounders. Methods 67 patients with bipolar I disorder, 43 with bipolar II disorder, and 86 randomly selected population-based healthy controls were compared. A number of neuropsychological tests were administered, assessing verbal and visual memory and executive functions. Patients were in a stable phase during testing. Results Patients with bipolar type I and type II were cognitively impaired compared to healthy controls, but there were no statistically significant differences between the two subtypes. The strongest predictor of cognitive impairment within the patient group was current antipsychotic treatment. Conclusions The present study suggests that the type and degree of cognitive dysfunction is similar in bipolar I and II patients. Notably, treatment with antipsychotics - but not a history of psychosis - was associated with more severe cognitive impairment. Given that patients with bipolar I disorder are more likely to be on antipsychotic drugs, this might explain why some previous studies have found that patients with type I bipolar disorder are more cognitively impaired than those with type II. PMID:23758923

2013-01-01

352

Monolithic GaAs interdigitated couplers  

NASA Astrophysics Data System (ADS)

This paper describes the design, fabrication, and performance of two monolithic GaAs C-band 90 deg interdigitated couplers with 50- and 25 omega impedances, respectively. A comparison of the performance of these two couplers shows that the 25-omega coupler has the advantages of lower loss and higher fabrication yield. The balanced amplifier configuration using 25 omega couplers will require a fewer number of elements in the input-output matching circuit of the FET amplifier. The fewer number of matching elements results in great savings in the GaAs real estate for microwave monolithic intergrated circuits. Both the couplers have been fabricated on a 0.1-mm-thick GaAs SI substrate. The measured results agree quite well with calculated results. The losses of the 50- and 25 omega couplers are 0.5 and 0.3 dB, respectively, over the 4-8-GHz frequency band.

Kumar, M.; Subbarao, S. N.; Menna, R. J.; Huang, H.-C.

1983-01-01

353

GaAs solar cell test facility  

NASA Astrophysics Data System (ADS)

A hybrid type (electricity and heat) GaAs solar cell test facility has been made to evaluate total characteristics of GaAs cell and to study the energy conversion system. The size of a solar collector is 3.4 m x 2.1 m and 60 GaAs cells with Fresnel lenses are attached on it. The solar collector is controlled by a microcomputer to track the sun. Electric energy produced by the cells is stored in a lead-acid battery and then supplied to the load through a DC-AC inverter. The microcomputer also controls the data acquisition in parallel with tracking. This paper presents an overview of the facility and the experimental results of power generation obtained to date.

Kawashima, M.; Hosoda, Y.; Suzawa, C.; Shimada, T.; Motoyoshi, K.; Sasatani, Y.

1982-01-01

354

Effectiveness of Adjunctive Antidepressant Treatment for Bipolar Depression  

Microsoft Academic Search

Background Episodes of depression are the most frequent cause of disability among patients with bipolar disorder. The effectiveness and safety of standard antidepressant agents for depressive episodes associated with bipolar disorder (bipolar depression) have not been well studied. Our study was designed to determine whether adjunctive antide- pressant therapy reduces symptoms of bipolar depression without increasing the risk of mania.

Gary S. Sachs; Andrew A. Nierenberg; Joseph R. Calabrese; Lauren B. Marangell; Stephen R. Wisniewski; Laszlo Gyulai; Edward S. Friedman; Charles L. Bowden; Mark D. Fossey; Michael J. Ostacher; Terence A. Ketter; Jayendra Patel; Peter Hauser; Daniel Rapport; James M. Martinez; Michael H. Allen; David J. Miklowitz; Michael W. Otto; Ellen B. Dennehy; Michael E. Thase

2007-01-01

355

Functioning and Disability in Bipolar Disorder: An Extensive Review  

Microsoft Academic Search

Background: Bipolar disorder has generally been regarded as having a better functional outcome than schizophrenia. However, studies have suggested low functioning in bipolar patients even when they are in clinical remission. Our aim was to determine the degree of functioning and disability in bipolar patients. Secondly, we reviewed factors potentially associated with the low functioning of bipolar patients. Method: The

J. Sanchez-Moreno; A. Martinez-Aran; R. Tabarés-Seisdedos; C. Torrent; E. Vieta; J. L. Ayuso-Mateos

2009-01-01

356

Harnessing denatured protein for controllable bipolar doping of a monolayer graphene.  

PubMed

In this work, we demonstrated tunable p- and/or n-type doping of chemical vapor deposition-grown graphene with the use of protein bovine serum albumin (BSA) as a dopant. BSA undergoes protonation or deprotonation reaction subject to solution pH, thereby acting as either an electron donor or an electron acceptor on the graphene surface layered with denatured BSA through ?-stacking interaction. This direct annealing of graphene with denatured BSA of amphoteric nature rendered facilitated fabrication of a p- and/or n-type graphene transistor by modulating pH-dependent net charges of the single dopant. Following AFM confirmation of the BSA/graphene interface assembly, the carrier transport properties of BSA-doped graphene transistors were assessed by I-V measurement and Raman spectra to show effective charge modulation of the graphene enabled by BSA doping at various pH conditions. The protein-mediated bipolar doping of graphene demonstrated in our work is simple, scalable, and straightforward; the proposed scheme is therefore expected to provide a useful alternative for fabricating graphene transistors of novel properties and promote their implementation in practice. PMID:25546483

Jang, Sung Kyu; Jang, Ji-Ryang; Choe, Woo-Seok; Lee, Sungjoo

2015-01-21

357

Insulin resistance and outcome in bipolar disorder.  

PubMed

Background Little is known about the impact of insulin resistance on bipolar disorder. Aims To examine the relationships between insulin resistance, type 2 diabetes and clinical course and treatment outcomes in bipolar disorder. Method We measured fasting glucose and insulin in 121 adults with bipolar disorder. We diagnosed type 2 diabetes and determined insulin resistance. The National Institute of Mental Health Life Chart was used to record the course of bipolar disorder and the Alda scale to establish response to prophylactic lithium treatment. Results Patients with bipolar disorder and type 2 diabetes or insulin resistance had three times higher odds of a chronic course of bipolar disorder compared with euglycaemic patients (50% and 48.7% respectively v. 27.3%, odds ratio (OR) = 3.07, P = 0.007), three times higher odds of rapid cycling (38.5% and 39.5% respectively v. 18.2%, OR = 3.13, P = 0.012) and were more likely to be refractory to lithium treatment (36.8% and 36.7% respectively v. 3.2%, OR = 8.40, P<0.0001). All associations remained significant after controlling for antipsychotic exposure and body mass index in sensitivity analyses. Conclusions Comorbid insulin resistance may be an important factor in resistance to treatment in bipolar disorder. PMID:25323142

Calkin, Cynthia V; Ruzickova, Martina; Uher, Rudolf; Hajek, Tomas; Slaney, Claire M; Garnham, Julie S; O'Donovan, M Claire; Alda, Martin

2015-01-01

358

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

ERIC Educational Resources Information Center

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…

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

2012-01-01

359

Geometry of Spatial Bipolar Fuzzy Sets Based on Bipolar Fuzzy Numbers and Mathematical Morphology  

Microsoft Academic Search

We propose in this paper new tools for dealing with bipolar fuzzy spatial information: particular geometrical objects are\\u000a defined, as well as measures such as cardinality and perimeter, represented as bipolar fuzzy numbers. A definition of distance\\u000a from a point to a bipolar fuzzy set is introduced as well. These definitions are based on mathematical morphology operators,\\u000a recently proposed in

Isabelle Bloch

2009-01-01

360

Composite substrate for bipolar electrodes  

DOEpatents

Substrates for electrode systems, particularly those to be used for bipolar electrodes in zinc-bromine batteries, are disclosed. The substrates preferably include carbon-black as a conductive filler in a polymeric matrix, with reinforcing materials such as glass fibers. Warpage of the zinc-bromine electrodes which was experienced in the prior art and which was believed to be caused by physical expansion of the electrodes due to bromine absorption by the carbon-black, is substantially eliminated when new substrate fabrication techniques are employed. In the pesent invention, substrates are prepared using a lamination process known as glass mat reinforced thermoplastics technology or, in an alternate embodiment, the substrate is made using a slurry process.

Tekkanat, Bora (Milwaukee, WI); Bolstad, James J. (Shorewood, WI)

1992-12-22

361

Composite substrate for bipolar electrodes  

DOEpatents

Substrates for electrode systems, particularly those to be used for bipolar electrodes in zinc-bromine batteries, are disclosed. The substrates preferably include carbon-black as a conductive filler in a polymeric matrix, with reinforcing materials such as glass fibers. Warpage of the zinc-bromine electrodes which was experienced in the prior art and which was believed to be caused by physical expansion of the electrodes due to bromine absorption by the carbon-black, is substantially eliminated when new substrate fabrication techniques are employed. In the present invention, substrates are prepared using a lamination process known as glass mat reinforced thermoplastics technology or, in an alternate embodiment, the substrate is made using a slurry process. 4 figs.

Tekkanat, B.; Bolstad, J.J.

1992-12-22

362

Bipolar battery and assembly method  

SciTech Connect

This patent describes a method of making a multicell electric storage battery having a container including a cover. It comprises a plurality of wall defining a plurality of individual cell compartments, one of the walls being an intercell partition separating one cell compartment from the next and having a section which is thicker than the remainder of the partition and adapted to receive intercell connector means therein, a galvanic cell element in each of the compartments comprising a stack of positive and negative polarity plates alternately interleaved one with the other and separated one from the other by an electrolyte permeable separator, an opening through the section in the partition providing a passage between adjacent cell compartments for electrically coupling the cell elements in the adjacent compartments, a mouth at each end of the opening each confronting one of the adjacent compartments, and intercell connector means electrically series connecting adjacent the cell elements together through the opening and comprising a plurality of electrically conductive links each joining a pair of substantially coplanar, opposite polarity plates into a bipolar electrode in which a positive polarity plate of a first cell element in one cell compartment is connected directly to a negative polarity plate in a second cell element in an adjacent cell compartment. It also comprises positioning barrier means between adjacent the electrodes in each the stack, the barrier means lying substantially contiguous with the mouths so as to define a region therebetween for receiving and retaining sealant injected thereinto; stacking the bipolar electrodes in the container so to form the cell elements in the compartments and such that the link for each electrode is substantially aligned in the opening with other links from other electrodes.

Bish, J.R.; Brutchen, G.W.; Boram, M.E.

1992-04-21

363

Miniature Bipolar Electrostatic Ion Thruster  

NASA Technical Reports Server (NTRS)

The figure presents a concept of a bipolar miniature electrostatic ion thruster for maneuvering a small spacecraft. The ionization device in the proposed thruster would be a 0.1-micron-thick dielectric membrane with metal electrodes on both sides. Small conical holes would be micromachined through the membrane and electrodes. An electric potential of the order of a volt applied between the membrane electrodes would give rise to an electric field of the order of several mega-volts per meter in the submicron gap between the electrodes. An electric field of this magnitude would be sufficient to ionize all the molecules that enter the holes. In a thruster-based on this concept, one or more propellant gases would be introduced into such a membrane ionizer. Unlike in larger prior ion thrusters, all of the propellant molecules would be ionized. This thruster would be capable of bipolar operation. There would be two accelerator grids - one located forward and one located aft of the membrane ionizer. In one mode of operation, which one could denote the forward mode, positive ions leaving the ionizer on the backside would be accelerated to high momentum by an electric field between the ionizer and an accelerator grid. Electrons leaving the ionizer on the front side would be ejected into free space by a smaller accelerating field. The equality of the ion and electron currents would eliminate the need for an additional electron- or ion-emitting device to keep the spacecraft charge-neutral. In another mode of operation, which could denote the reverse mode, the polarities of the voltages applied to the accelerator grids and to the electrodes of the membrane ionizer would be the reverse of those of the forward mode. The reversal of electric fields would cause the ion and electrons to be ejected in the reverse of their forward mode directions, thereby giving rise to thrust in the direction opposite that of the forward mode.

Hartley, Frank T.

2006-01-01

364

Reliability evaluation of GaAs FETS  

Microsoft Academic Search

The objective of this program was to assess and establish the reliability and life characteristics of commercially available, medium power GaAs MESFETs and to identify any associated failure mechanisms. The devices chosen for this study were the TI MSX802 and laboratory devices and devices from three other manufacturers, A, B, and C. All devices were hermetically packaged and had approximately

H. M. Macksey

1981-01-01

365

Displacement damage in GaAs structures  

Microsoft Academic Search

High energy knock-on atoms produced by incident protons are much more important in determining the total nonionizing energy deposited in GaAs than in Si, due to the relative size of the Lindhard correction for partitioning the recoil energy. High energy recoils are mainly produced by inelastic nuclear interactions between the incident protons and the target atoms. A review of previous

G. P. Summers; M. A. Xapsos; C. J. Dale; P. W. Marshall; E. L. Petersen; E. A. Burke

1988-01-01

366

High Performance Silicon Nanowire Field Effect Transistors  

Microsoft Academic Search

Silicon nanowires can be prepared with single-crystal structures, diameters as small as several nanometers and controllable hole and electron doping, and thus represent powerful building blocks for nanoelectronics devices such as field effect transistors. To explore the potential limits of silicon nanowire transistors, we have examined the influence of source-drain contact thermal annealing and surface passivation on key transistor properties.

Yi Cui; Zhaohui Zhong; Deli Wang; Wayne U. Wang; Charles M. Lieber

2003-01-01

367

Transparent and Flexible Carbon Nanotube Transistors  

E-print Network

Transparent and Flexible Carbon Nanotube Transistors E. Artukovic, M. Kaempgen, D. S. Hecht, S We report the fabrication of transparent and flexible transistors where both the bottom gate not influence the transmission in the visible spectral range. The quest for flexible and transparent transistors

Gruner, George

368

Integration of Cell Membranes and Nanotube Transistors  

E-print Network

Integration of Cell Membranes and Nanotube Transistors Keith Bradley, Alona Davis, Jean. As the nanoelectronic device, we use a nanotube network transistor, which incorporates many individual nanotubes as transistors, and that the two systems interact. Further, we use the interaction to study the charge

Gruner, George

369

Legal Issues of Pediatric Bipolar Disorder  

MedlinePLUS

Home » Learn » Library Legal Issues of Pediatric Bipolar Disorder January 21, 2010 Overview Health insurance Child custody Allegations of abuse The juvenile justice system Consent for treatment Disclosure of medical information Finding ...

370

Hippocampal function in schizophrenia and bipolar disorder   

E-print Network

Background. The hippocampus plays a central role in memory formation. There is considerable evidence of abnormalities in hippocampal structure and function in schizophrenia, which may differentiate it from bipolar disorder. ...

Hall, J.; Whalley, H. C.; Marwick, K.; McKirdy, J.; Sussmann, J.; Romaniuk, L.; Johnstone, E. C.; Wan, H. I.; McIntosh, A. M.; Lawrie, S. M.

371

Restoring functioning in bipolar disorder: functional remediation.  

PubMed

Over the past several years, many evidence-based interventions have proven to be effective as adjunctive therapies in the treatment of bipolar disorder. Only a few, however, have addressed the issue of functional recovery in bipolar euthymic patients, which is difficult to achieve after an affective episode. The functional remediation program has been designed at the Hospital Clinic of Barcelona with the main aim of treating functional impairment in bipolar disorder. The program consists of 21 weekly group sessions and is based on a neuro-cognitive-behavioral approach. Throughout the sessions, euthymic patients are trained in the use of neurocognitive skills to be applied during their daily routines. Modeling techniques, role playing, self-instructions, verbal instructions, positive reinforcement, and metacognitive cues are some of the techniques that are used in the program. The present report aims at explaining this new intervention to improve functional outcomes in euthymic bipolar patients. PMID:25377603

Bonnin, Caterina M; Torrent, Carla; Vieta, Eduard; Martínez-Arán, Anabel

2014-01-01

372

Bipolar separator plate for electrochemical cells  

SciTech Connect

Shunt currents which flow between the electrodes of adjacent cells through the moving conductive fluid and the fluid pool in the manifold of a bipolar cell assembly are minimized by introducing the conductive fluid at the top of an elongated outlet manifold. This results in cascaded flow which interrupts the current path. Shunt currents between the fluid manifold walls of the conductive bipolar elements in the series connected electrochemical cell assemblies are minimized by insulating the manifold walls with insulating, elastomeric sealing grommets. This prevents current flow between the manifold walls through the electrically conductive fluid in the manifold and provides an edgeseal between bipolar plates. The instant invention relates to a process and apparatus for electrochemical cell assemblies and more particularly, for reducing shunt current in series connected bipolar assemblies.

Balko, E. N.; Moulthrop, L. W.

1985-08-06

373

Bipolar Disorder in Children and Adolescents  

MedlinePLUS

... be monitored carefully by a doctor. 29 Atypical antipsychotics are sometimes used to treat symptoms of bipolar ... 31 What are the side effects of atypical antipsychotics? Side effects of many atypical antipsychotics include: Drowsiness ...

374

White matter microstructure alterations in bipolar disorder.  

PubMed

Genetic, neuropathological and magnetic resonance imaging findings support the presence of diffuse white matter cytoarchitectural disruption in bipolar disorder. In this study, diffusion-weighted imaging (DWI) was applied to study cortical white matter microstructure organisation in 24 patients with DSM-IV bipolar disorder and 35 matched normal controls. DWI images were obtained using a 1.5 Tesla scanner and apparent diffusion coefficient (ADC) values were determined over regions of interest placed, bilaterally, in the frontal, temporal, parietal, and occipital white matter. Significantly increased ADC values were found in bipolar patients with respect to normal controls in the right temporal lobe, left parietal lobe and bilateral occipital lobes. ADC values did not associate significantly with age or with clinical variables (p>0.05). Diffuse cortical white matter alterations on DWI in bipolar disorder denote widespread disruption of white matter integrity and may be due to altered myelination and/or axonal integrity. PMID:22687164

Bellani, Marcella; Perlini, Cinzia; Ferro, Adele; Cerruti, Stefania; Rambaldelli, Gianluca; Isola, Miriam; Cerini, Roberto; Dusi, Nicola; Andreone, Nicola; Balestrieri, Matteo; Pozzi Mucelli, Roberto; Tansella, Michele; Brambilla, Paolo

2012-01-01

375

White matter microstructure alterations in bipolar disorder  

PubMed Central

Summary Genetic, neuropathological and magnetic resonance imaging findings support the presence of diffuse white matter cytoarchitectural disruption in bipolar disorder. In this study, diffusion-weighted imaging (DWI) was applied to study cortical white matter microstructure organisation in 24 patients with DSM-IV bipolar disorder and 35 matched normal controls. DWI images were obtained using a 1.5 Tesla scanner and apparent diffusion coefficient (ADC) values were determined over regions of interest placed, bilaterally, in the frontal, temporal, parietal, and occipital white matter. Significantly increased ADC values were found in bipolar patients with respect to normal controls in the right temporal lobe, left parietal lobe and bilateral occipital lobes. ADC values did not associate significantly with age or with clinical variables (p>0.05). Diffuse cortical white matter alterations on DWI in bipolar disorder denote widespread disruption of white matter integrity and may be due to altered myelination and/or axonal integrity. PMID:22687164

Bellani, Marcella; Perlini, Cinzia; Ferro, Adele; Cerruti, Stefania; Rambaldelli, Gianluca; Isola, Miriam; Cerini, Roberto; Dusi, Nicola; Andreone, Nicola; Balestrieri, Matteo; Mucelli, Roberto Pozzi; Tansella, Michele; Brambilla, Paolo

2012-01-01

376

Memory and Learning in Pediatric Bipolar Disorder  

Microsoft Academic Search

ObjectiveTo test the hypothesis that patients with pediatric bipolar disorder (PBPD) would demonstrate impairment relative to diagnosis-free controls of comparable age, gender, and IQ on measures of memory functioning.

Erin B McClure; Julia E Treland; Joseph Snow; Daniel P Dickstein; Kenneth E Towbin; Dennis S Charney; Daniel S Pine; Ellen Leibenluft

2005-01-01

377

Subnanosecond photoconductive switching in GaAs  

SciTech Connect

We are conducting research in photoconductive switching for the purpose of generating microwave pulses with amplitudes up to 50 kV. This technology has direct application to impulse radar and HPM sources. We are exploiting the very fast recombination rates of Gallium Arsenide (GaAs) to explore the potential of GaAs as an on-off switch when operating in the linear mode (the linear mode is defined such that one carrier pair is generated for each photon absorbed). In addition, we are exploring the potential of GaAs to act as a closing switch in avalanche'' mode at high fields. We have observed switch closing times of less than 200 psec with 100 psec duration laser pulse and opening times of less than 400 psec with neutron irradiated GaAs at fields of tens of kV/cm. If the field is increased and the laser energy decreased, the laser can be used to trigger photoconductive switches into an avalanche'' mode of operation in which carrier multiplication occurs. This mode of operation is quite promising since the switches close in less than 1 nsec while realizing significant energy gain (ratio of electrical energy in the pulse to optical trigger energy). We are currently investigating both large are (1 sq cm) and small area (<1 sq mm) switches illuminated by GaAlAs laser diodes at 900 nm and Nd:YAG lasers at 1.06 micrometers. Preliminary results indicate that the closing time of the avalanche switches depends primarily on the material properties of the devices with closing times of 300--1300 psec at voltages of 6-35 kV. We will present experimental results for linear, lock on and avalanche mode operation of GaAs photoconductive switches and how these pulses may be applied to microwave generation. 3 refs., 11 figs.

Druce, R.L.; Pocha, M.D.; Griffin, K.L.

1990-01-01

378

Subnanosecond photoconductive switching in GaAs  

SciTech Connect

We are conducting research in photoconductive switching for the purpose of generating microwave pulses with amplitudes up to 50 kV. This technology has direct application to impulse radar and HPM sources. We are exploiting the very fast recombination rates of Gallium Arsenide (GaAs) to explore the potential of GaAs as an on-off switch when operating in the linear mode (the linear mode is defined such that one carrier pair is generated for each photon absorbed). In addition, we are exploring the potential GaAs to act as a closing switch in avalanche'' mode at high fields. We have observed switch closing times of less than 200 psec with a 100 psec duration laser pulse and opening times of less than 400 psec with neutron irradiated GaAs at fields of tens of kV/cm. If the field is increased and the laser energy decreased, the laser can be used to trigger photoconductive switches into avalanche'' mode of operation in which carrier multiplication occurs. This mode of operation is quite promising since the switches close in less than 1 nsec while realizing significant energy gain (ratio of electrical energy in the pulse to optical trigger energy). We are currently investigating both large area (1 sq cm) and small area (< 1 sq mm) switches illuminated by GaAlAs laser diodes at 900 nm and Nd:YAG lasers at 1.06 micrometers. Preliminary results indicate that the closing time of the avalanche switches depends primarily on the material properties of the devices with closing times of 300--1300 psec at voltages of 6--35 kV. We will present experimental results for linear, lock on and avalanche mode operation of GaAs photoconductive switches and how these pulses may be applied to microwave generation. 3 refs.

Druce, R.L.; Pocha, M.D.; Griffin, K.L.

1991-04-01

379

Subnanosecond photoconductive switching in GaAs  

SciTech Connect

We are conducting research in photoconductive switching for the purpose of generating microwave pulses with amplitudes up to 50 kV. This technology has direct application to impulse radar and HPM sources. We are exploiting the very fast recombination rates of Gallium Arsenide (GaAs) to explore the potential of GaAs as an on-off switch when operating in the linear mode (the linear mode is defined such that one carrier pair is generated for each photon absorbed). In addition, we are exploring the potential GaAs to act as a closing switch in ``avalanche`` mode at high fields. We have observed switch closing times of less than 200 psec with a 100 psec duration laser pulse and opening times of less than 400 psec with neutron irradiated GaAs at fields of tens of kV/cm. If the field is increased and the laser energy decreased, the laser can be used to trigger photoconductive switches into ``avalanche`` mode of operation in which carrier multiplication occurs. This mode of operation is quite promising since the switches close in less than 1 nsec while realizing significant energy gain (ratio of electrical energy in the pulse to optical trigger energy). We are currently investigating both large area (1 sq cm) and small area (< 1 sq mm) switches illuminated by GaAlAs laser diodes at 900 nm and Nd:YAG lasers at 1.06 micrometers. Preliminary results indicate that the closing time of the avalanche switches depends primarily on the material properties of the devices with closing times of 300--1300 psec at voltages of 6--35 kV. We will present experimental results for linear, lock on and avalanche mode operation of GaAs photoconductive switches and how these pulses may be applied to microwave generation. 3 refs.

Druce, R.L.; Pocha, M.D.; Griffin, K.L.

1991-04-01

380

A Si bipolar monolithic RF bandpass amplifier  

NASA Astrophysics Data System (ADS)

The application of monolithic inductors to the realization of Si bipolar monolithic RF amplifiers is investigated. As a test vehicle, a bipolar monolithic bandpass amplifier was fabricated and characterized. A 4-nH silicon integrated inductor was used to achieve a peak S21 gain of 8 dB, a simulated noise figure of 6.4 dB, and a matched input impedance of 50 ohm in the frequency range of 1-2 GHz.

Nguyen, Nhat M.; Meyer, Robert G.

1992-01-01

381

Suicide risk and prevention in bipolar disorder  

Microsoft Academic Search

Bipolar disorders are prevalent and severe illnesses that are associated with a high risk of suicide. Patients with bipolar\\u000a disorder who have had prior suicide attempts are at a substantially higher risk for future suicidality, even after controlling\\u000a for other risk factors. Despite the magnitude of this problem, there is a paucity of controlled prospective data to guide\\u000a clinical care,

Lauren B. Marangell; James M. Martinez; Melissa Martinez; Holly A. Zboyan; Ryan Al Jurdi

2006-01-01

382

Bipolar disorder: Strategies for the lifelong illness  

Microsoft Academic Search

Bipolar disorder has a lifelong course. Our understanding of the illness is not complete enough to detect it before the first\\u000a manic or hypomanic episode. Treatment of bipolar disorder has three phases. The continuation phase comprises the transition\\u000a between symptomatic improvement after correct diagnosis and effective treatment of an episode and functional recovery. This\\u000a phase requires continuation of effective pharmacologic

Alan C. Swann

2006-01-01

383

Mexiletine in treatment-resistant bipolar disorder  

Microsoft Academic Search

Background: The purpose of this study was to evaluate the efficacy and safety of mexiletine, a medication with antiarrhythmic, anticonvulsant and analgesic properties, in treatment-resistant bipolar disorder patients. Methods: Twenty subjects with rapid-cycling bipolar disorder who had failed to respond or were intolerant to lithium, valproic acid and carbamazepine were entered into the 6-week, open label study. Subjects were followed

Ayal Schaffer; Anthony J Levitt; Russell T Joffe

2000-01-01

384

Bipolar outflows in OH\\/IR stars  

Microsoft Academic Search

We investigate the development of bipolar outflows during the early post-AGB evolution. A sample of 10 OH\\/IR stars with irregular OH spectra and unusually large expansion velocities is observed at high angular resolution. The sample includes bipolar nebulae (e.g., OH231.8+4.2), bright post-AGB stars (HD 101584) and reflection nebulae (e.g., Roberts 22). The IRAS colour-colour diagram separates the sample into different

Albert A. Zijlstra; J. M. Chapman; P. te Lintel Hekkert; L. Likkel; F. Comeron; R. P. Norris; F. J. Molster; R. J. Cohen

2001-01-01

385

Acoustic Wave Chemical Microsensors in GaAs  

SciTech Connect

High sensitivity acoustic wave chemical microsensors are being developed on GaAs substrates. These devices take advantage of the piezoelectric properties of GaAs as well as its mature microelectronics fabrication technology and nascent micromachining technology. The design, fabrication, and response of GaAs SAW chemical microsensors are reported. Functional integrated GaAs SAW oscillators, suitable for chemical sensing, have been produced. The integrated oscillator requires 20 mA at 3 VK, operates at frequencies up to 500 MHz, and occupies approximately 2 mmz. Discrete GaAs sensor components, including IC amplifiers, SAW delay lines, and IC phase comparators have been fabricated and tested. A temperature compensation scheme has been developed that overcomes the large temperature dependence of GaAs acoustic wave devices. Packaging issues related to bonding miniature flow channels directly to the GaAs substrates have been resolved. Micromachining techniques for fabricating FPW and TSM microsensors on thin GaAs membranes are presented and GaAs FPW delay line performance is described. These devices have potentially higher sensitivity than existing GaAs and quartz SAW sensors.

Albert G. Baca; Edwin J. Heller; Gregory C. Frye-Mason; John L. Reno; Richard Kottenstette; Stephen A. Casalnuovo; Susan L. Hietala; Vincent M. Hietala

1998-09-20

386

Revisiting the ``Spin-Transistor''  

NASA Astrophysics Data System (ADS)

A ``spin-transistor'' in principle requires efficient injection (source), efficient detection (drain) and electrical manipulation (gate). For sometime now, electrical manipulation based on the Rashba effect has been well established and in recent years there has been significant progress in the design of injectors and detectors. Lateral spin-valve structures showing ˜50% spin-polarization has been reported. In view of these advances it seems appropriate to evaluate various ``spin- transistor'' concepts. With this in mind, we have developed non- equilibrium Green's function (NEGF) based model and benchmarked against existing experiments.

Naser Zainuddin, Abu; Siddiqui, Lutfe; Datta, Supriyo

2009-03-01

387

Characteristics of a micromachined floating-gate high-electron-mobility transistor at 4.2 K  

NASA Astrophysics Data System (ADS)

We use micromachined, free-standing Ni cantilevers to develop a mechanical field-effect transistor based on III-V material systems. The device consists of an electrostatically actuated microcantilever, acting as the floating gate, fabricated over a defined two-dimensional electron gas (2DEG) in a modulation-doped GaAs /AlGaAs heterostructure. The gating effects on the conductance of the 2DEG channel of the biased floating gate at different operating points are studied at 4.2K. Preliminary resonance measurements based on the 2DEG as a deflection sensor are presented.

Teh, W. H.; Crook, R.; Smith, C. G.; Beere, H. E.; Ritchie, D. A.

2005-06-01

388

Treatment Guidelines for Children and Adolescents With Bipolar Disorder: Child Psychiatric Workgroup on Bipolar Disorder  

Microsoft Academic Search

Clinicians who treat children and adolescents with bipolar disorder desperately need current treatment guidelines. These guidelines were developed by expert consensus and a review of the extant literature about the diagnosis and treatment of pediatric bipolar disorders. The four sections of these guidelines include diagnosis, comorbidity, acute treatment, and main- tenance treatment. These guidelines are not intended to serve as

ROBERT A. KOWATCH; MARY FRISTAD; BORIS BIRMAHER; KAREN DINEEN WAGNER; ROBERT L. FINDLING; MARTHA HELLANDER

389

Subcortical Gray Matter Volume Abnormalities in Healthy Bipolar Offspring: Potential Neuroanatomical Risk Marker for Bipolar Disorder?  

ERIC Educational Resources Information Center

A study is conducted to examine the extent to which bipolar disorder (BD) is associated with gray matter volume abnormalities in brain regions in healthy bipolar offspring relative to age-matched controls. Results show increased gray matter volume in the parahippocampus/hippocampus in healthy offspring at genetic risk for BD.

Ladouceur, Cecile D.; Almeida, Jorge R. C.; Birmaher, Boris; Axelson, David A.; Nau, Sharon; Kalas, Catherine; Monk, Kelly; Kupfer, David J.; Phillips, Mary L.

2008-01-01

390

Clinical, Demographic, and Familial Correlates of Bipolar Spectrum Disorders among Offspring of Parents with Bipolar Disorder  

ERIC Educational Resources Information Center

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,…

Goldstein, Benjamin I.; Shamseddeen, Wael; Axelson, David A.; Kalas, Cathy; Monk, Kelly; Brent, David A.; Kupfer, David J.; Birmaher, Boris

2010-01-01

391

Effects of Sulfide Passivation on the Performance of GaAs MISFETs with Photo-CVD Grown P3N5 Gate Insulators  

Microsoft Academic Search

Accumulation-mode and depletion-mode GaAs metal-insulator-semiconductor field-effect transistors (MISEETs), with sulfur-treatment and a photochemical vapor-deposited- P3N5 gate insulator, have been successfully fabricated. The devices have good linearity, low hysteresis in current-voltage characteristics, and the instability of the current less than 22 percent for the period of 1.0-1.0×104 s. The effective electron mobility and extrinsic transconductance of the FETs at room temperature

Yoon-Ha Jeong; Ki-Hwan Choi; Seong-Kue Jo; Bongkoo Kang

1995-01-01

392

Thresholds for Cenozoic bipolar glaciation.  

PubMed

The long-standing view of Earth's Cenozoic glacial history calls for the first continental-scale glaciation of Antarctica in the earliest Oligocene epoch ( approximately 33.6 million years ago), followed by the onset of northern-hemispheric glacial cycles in the late Pliocene epoch, about 31 million years later. The pivotal early Oligocene event is characterized by a rapid shift of 1.5 parts per thousand in deep-sea benthic oxygen-isotope values (Oi-1) within a few hundred thousand years, reflecting a combination of terrestrial ice growth and deep-sea cooling. The apparent absence of contemporaneous cooling in deep-sea Mg/Ca records, however, has been argued to reflect the growth of more ice than can be accommodated on Antarctica; this, combined with new evidence of continental cooling and ice-rafted debris in the Northern Hemisphere during this period, raises the possibility that Oi-1 represents a precursory bipolar glaciation. Here we test this hypothesis using an isotope-capable global climate/ice-sheet model that accommodates both the long-term decline of Cenozoic atmospheric CO(2) levels and the effects of orbital forcing. We show that the CO(2) threshold below which glaciation occurs in the Northern Hemisphere ( approximately 280 p.p.m.v.) is much lower than that for Antarctica ( approximately 750 p.p.m.v.). Therefore, the growth of ice sheets in the Northern Hemisphere immediately following Antarctic glaciation would have required rapid CO(2) drawdown within the Oi-1 timeframe, to levels lower than those estimated by geochemical proxies and carbon-cycle models. Instead of bipolar glaciation, we find that Oi-1 is best explained by Antarctic glaciation alone, combined with deep-sea cooling of up to 4 degrees C and Antarctic ice that is less isotopically depleted (-30 to -35 per thousand) than previously suggested. Proxy CO(2) estimates remain above our model's northern-hemispheric glaciation threshold of approximately 280 p.p.m.v. until approximately 25 Myr ago, but have been near or below that level ever since. This implies that episodic northern-hemispheric ice sheets have been possible some 20 million years earlier than currently assumed (although still much later than Oi-1) and could explain some of the variability in Miocene sea-level records. PMID:18833277

Deconto, Robert M; Pollard, David; Wilson, Paul A; Pälike, Heiko; Lear, Caroline H; Pagani, Mark

2008-10-01

393

GAAS shallow-homojunction solar cells. Final report  

SciTech Connect

The feasibility of fabricating space resistant, high efficiency, light weight, low cost GaAs shallow homojunction solar cells for space application is investigated. The material preparation of ultrathin GaAs single crystal layers, and the fabrication of efficient GaAs solar cells on bulk GaAs substrates are discussed. Considerable progress was made in both areas, and conversion efficiency about 16% AMO was obtained using anodic oxide as a single layer antireflection coating. A computer design shows that even better cells can be obtained with double layer antireflection coating. Ultrathin, high efficiency solar cells were obtained from GaAs films prepared by the CLEFT process, with conversion efficiency as high as 17% at AMI from a 10 micrometers thick GaAs film. A organometallic CVD was designed and constructed.

Fan, J.C.C.

1981-06-01

394

LEC GaAs for integrated circuit applications  

NASA Technical Reports Server (NTRS)

Recent developments in liquid encapsulated Czochralski techniques for the growth of semiinsulating GaAs for integrated circuit applications have resulted in significant improvements in the quality and quantity of GaAs material suitable for device processing. The emergence of high performance GaAs integrated circuit technologies has accelerated the demand for high quality, large diameter semiinsulating GaAs substrates. The new device technologies, including digital integrated circuits, monolithic microwave integrated circuits and charge coupled devices have largely adopted direct ion implantation for the formation of doped layers. Ion implantation lends itself to good uniformity and reproducibility, high yield and low cost; however, this technique also places stringent demands on the quality of the semiinsulating GaAs substrates. Although significant progress was made in developing a viable planar ion implantation technology, the variability and poor quality of GaAs substrates have hindered progress in process development.

Kirkpatrick, C. G.; Chen, R. T.; Homes, D. E.; Asbeck, P. M.; Elliott, K. R.; Fairman, R. D.; Oliver, J. D.

1984-01-01

395

GaAs shallow-homojunction solar cells  

NASA Technical Reports Server (NTRS)

The feasibility of fabricating space resistant, high efficiency, light weight, low cost GaAs shallow homojunction solar cells for space application is investigated. The material preparation of ultrathin GaAs single crystal layers, and the fabrication of efficient GaAs solar cells on bulk GaAs substrates are discussed. Considerable progress was made in both areas, and conversion efficiency about 16% AMO was obtained using anodic oxide as a single layer antireflection coating. A computer design shows that even better cells can be obtained with double layer antireflection coating. Ultrathin, high efficiency solar cells were obtained from GaAs films prepared by the CLEFT process, with conversion efficiency as high as 17% at AMI from a 10 micrometers thick GaAs film. A organometallic CVD was designed and constructed.

Fan, J. C. C.

1981-01-01

396

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

PubMed Central

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. PMID:24030475

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, Ay?egül; 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, Ay?egül; 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

397

Bipolar janus particle assembly in microdevice.  

PubMed

In recent years, there are significant interests in the manipulation of bipolar Janus particles. In this article we investigate the transient behavior of the electro-orientation process and particle-particle interaction of ellipsoidal bipolar Janus particles in the presence and absence of a DC electric field. The bipolar particle dynamics is modeled with a body force term in the fluid flow equations based on the Maxwell stress tensor. This force is due to presence of bipolar surface charges on the particles as well as their interactions with an imposed field. An interface resolved numerical scheme that consider the finite size of the particle is adopted for computation of the electric and flow fields. Our numerical results show that in the absence of an electric field, particles can undergo self-orientation to reach an equilibrium position. The time taken to reach a stable orientation depends on the initial configuration and inter-particle separation distance. Bipolar particles experience forces only on their polar ends, a phenomena that is difficult to capture with non-interface resolved methods. When bipolar particles are exposed to an external electric field, they rotate to align along the external electric field direction. Depending upon the initial configuration, particles orient via clockwise or counter clockwise rotations to form head to tail chains. The time required to form particle assembly strongly depends on particle size and bipolar charge density. The present numerical algorithm can be applied to a wider class of dual-faced Janus particles. This article is protected by copyright. All rights reserved. PMID:25475510

Hossan, Mohammad R; Gopmandal, Partha P; Dillon, Robert; Dutta, Prashanta

2014-12-01

398

TRANSISTOR PREAMPLIFIER FOR NEUTRON MONITORS  

Microsoft Academic Search

The design and performance of several transistor impedance matching ; circuits are discussed. The most satisfactory circuit is capable of operation up ; to 80 deg C and was tested to 100 deg C. The pre-amplifier which is potted with ; silicone rubber and attached to a waterproof BFâ tube, may be operated ; while submerged in water. Acid atmospheres

1960-01-01

399

Orientation effects in Bipolar nebulae  

E-print Network

We show that the inclination to the line of sight of bipolar nebulae strongly affects some of their observed properties. We model these objects as having a spherically symmetric Planetary Nebula and a dusty equatorial density enhancement that produces extinction that varies with the viewing angle. Our sample of 29 nebulae taken from the literature shows a clear correlation between the inclination angle and the near-IR and optical photometric properties as well as the apparent luminosity of the objects. As the inclination angle increases --the viewing angle is closer to the equatorial plane-- the objects become redder, their average apparent luminosity decreases, and their average projected expansion velocity becomes smaller. We compute two-dimensional models of stars embedded in dusty disks of various shapes and compositions and show that the observed data can be reproduced by disk-star combinations with reasonable parameters. To compare with the observational data, we generate sets of model data by randomly varying the star and disk parameters within a physically meaningful range. We conclude that a only a smooth pole to equator density gradient agrees with the observed phenomena and that thin, equatorially concentrated disks can be discarded.

Hugo E. Schwarz; Hektor Monteiro; Ryan Peterson

2006-09-17

400

Bipolar disorder and neurophysiologic mechanisms  

PubMed Central

Recent studies have suggested that some variants of bipolar disorder (BD) may be due to hyperconnectivity between orbitofrontal (OFC) and temporal pole (TP) structures in the dominant hemisphere. Some initial MRI studies noticed that there were corpus callosum abnormalities within specific regional areas and it was hypothesized that developmentally this could result in functional or effective connectivity changes within the orbitofrontal-basal ganglia-thalamocortical circuits. Recent diffusion tensor imaging (DTI) white matter fiber tractography studies may well be superior to region of interest (ROI) DTI in understanding BD. A “ventral semantic stream” has been discovered connecting the TP and OFC through the uncinate and inferior longitudinal fasciculi and the elusive TP is known to be involved in theory of mind and complex narrative understanding tasks. The OFC is involved in abstract valuation in goal and sub-goal structures and the TP may be critical in binding semantic memory with person–emotion linkages associated with narrative. BD patients have relative attenuation of performance on visuoconstructional praxis consistent with an atypical localization of cognitive functions. Multiple lines of evidence suggest that some BD alleles are being selected for which could explain the enhanced creativity in higher-ability probands. Associations between ROI’s that are not normally connected could explain the higher incidence of artistic aptitude, writing ability, and scientific achievements among some mood disorder subjects. PMID:19337455

McCrea, Simon M

2008-01-01

401

UV laser activated digital etching of GaAs  

SciTech Connect

The self-limited etching characteristics of digital etching employing an UV laser/Cl{sub 2}/GaAs system are presented. The self-limiting nature is the key mechanism and plays an important role in digital etching for obtaining etch rates independent of etching parameters. Surface processes based on photodissociation of physisorbed chlorine on GaAs with diffusion of negatively charged Cl into GaAs are also discussed.

Meguro, T.; Aoyagi, Y. [RIKEN, Wako, Saitama (Japan). Inst. of Physical and Chemical Research

1996-12-31

402

Development of GaAs solar cells  

NASA Technical Reports Server (NTRS)

This is the second quarterly technical report on a program, the goal of which is to achieve high efficiency GaAs solar cells. Analysis was concerned with providing design information for use in experimentally determining optimum solar cell process parameters. The first quarterly report contained the results of those design calculations. Using those results as a guide, experimental work was initiated to determine optimum cell process parameters. The initial results on this phase of the program are reported.

Mcnally, P. J.

1972-01-01

403

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

NASA Astrophysics Data System (ADS)

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 using a UV-Ozone treatment to shift the threshold voltage and increase the current of the transistor under both compressive and tensile strain. An array of strain sensors which maps the strain field on a PVDF film surface is demonstrated in this work. The strain sensor experience inspires a tone analyzer built using distributed resonator architecture on a tensioned piezoelectric PVDF sheet. This sheet is used as both the resonator and detection element. Two architectures are demonstrated; one uses distributed directly addressed elements as a proof of concept, and the other integrates organic thin film transistor-based transimpedance amplifiers monolithically with the PVDF sheet to convert the piezoelectric charge signal into a current signal for future applications such as sound field imaging. The PVDF sheet material is instrumented along its length and the amplitude response at 15 sites is recorded and analyzed as a function of the frequency of excitation. The determination of the dominant frequency component of an incoming sound is demonstrated using linear system decomposition of the time-averaged response of the sheet using no time domain detection. Our design allows for the determination of the spectral composition of a sound using the mechanical signal processing provided by the amplitude response and eliminates the need for time-domain electronic signal processing of the incoming signal. The concepts of the PVDF strain sensor and the tone analyzer trigger the idea of an active matrix microphone through the integration of organic thin film transistors with a freestanding piezoelectric polymer sheet. Localized acoustic pressure detection is enabled by switch transistors and local transimpedance amplification built into the active matrix architecture. The frequency of detection ranges from DC to 15KHz; the bandwidth is extended using an architecture that provides for virtually zero gate/source and gate/drain capacitance at the sensing transistors and low overlap capacitance at the switch transistors. A series of measurements are taken to demonstrate localized

Hsu, Yu-Jen

404

Thermoelectric Effects in Bipolar Devices: Internally Cooled Semiconductor Lasers  

E-print Network

Thermoelectric Effects in Bipolar Devices: Internally Cooled Semiconductor Lasers Kevin P. Pipe likewise neglected several microscopic heat exchange processes such as thermoelectric effects that occur to thermoelectric effects. Transport in semiconductor lasers is distinguished by its bipolar nature. Current

405

Genetic determinants of white matter integrity in bipolar disorder   

E-print Network

Bipolar disorder is a heritable psychiatric disorder, and several of the genes associated with bipolar disorder and related psychotic disorders are involved in the development and maintenance of white matter in the brain. ...

Sprooten, Emma

2012-06-30

406

Anxiety symptoms and syndromes in bipolar children and adolescents  

Microsoft Academic Search

Anxiety disorders are relatively common in children and adolescents with bipolar disorder. Research to date indicates they\\u000a may impact the onset, course, and treatment response of bipolar illness in children. Anxiety disorders often precede the onset\\u000a of pediatric bipolar disorder. Family studies suggest first-degree relatives of bipolar patients are at increased risk for\\u000a developing mood and anxiety disorders compared with

Edith M. Jolin; Elizabeth B. Weller; Ronald A. Weller

2008-01-01

407

Ventral anterior cingulate connectivity distinguished nonpsychotic bipolar illness from psychotic bipolar disorder and schizophrenia.  

PubMed

Bipolar illness is a debilitating neuropsychiatric disorder associated with alterations in the ventral anterior cingulate cortex (vACC), a brain region thought to regulate emotional behavior. Although recent data-driven functional connectivity studies provide evidence consistent with this possibility, the role of vACC in bipolar illness and its pattern of whole brain connectivity remain unknown. Furthermore, no study has established whether vACC exhibits differential whole brain connectivity in bipolar patients with and without co-occurring psychosis and whether this pattern resembles that found in schizophrenia. We conducted a human resting-state functional connectivity investigation focused on the vACC seed in 73 remitted bipolar I disorder patients (33 with psychosis history), 56 demographically matched healthy comparison subjects, and 73 demographically matched patients with chronic schizophrenia. Psychosis history within the bipolar disorder group corresponded with significant between-group connectivity alterations along the dorsal medial prefrontal surface when using the vACC seed. Patients with psychosis history showed reduced connectivity (Cohen's d = -0.69), whereas those without psychosis history showed increased vACC coupling (Cohen's d = 0.8) relative to controls. The vACC connectivity observed in chronic schizophrenia patients was not significantly different from that seen in bipolar patients with psychosis history but was significantly reduced compared with that in bipolar patients without psychosis history. These robust findings reveal complex vACC connectivity alterations in bipolar illness, which suggest differences depending on co-occurrence of lifetime psychosis. The similarities in vACC connectivity patterns in schizophrenia and psychotic bipolar disorder patients may suggest the existence of common mechanisms underlying psychotic symptoms in the two disorders. PMID:24782562

Anticevic, Alan; Savic, Aleksandar; Repovs, Grega; Yang, Genevieve; McKay, D Reese; Sprooten, Emma; Knowles, Emma E; Krystal, John H; Pearlson, Godfrey D; Glahn, David C

2015-01-01

408

Bi-polar Supernova Explosions  

E-print Network

We discuss the optical spectropolarimetry of several core-collapse supernovae, SN 1996cb (Type IIB), SN 1997X (Type Ic), and SN 1998S (Type IIn). The data show polarization evolution of several spectral features at levels from 0.5% to above 4%. The observed line polarization is intrinsic to the supernovae and not of interstellar origin. These data suggest that the the distribution of ejected matter is highly aspherical. In the case of SN 1998S, the minimum major to minor axis ratio must be larger than 2.5 to 1 if the polarization is 3% from an oblate spheroidal ejecta seen edge on. A well-defined symmetry axis can be deduced from spectropolarimetry for the peculiar Type IIn supernova SN 1998S but the Type IIB events SN 1993J and SN 1996cb seem to possess much more complicated geometries with polarization position angles showing larger irregular variations across spectral features; the latter may be associated with large scale clumpiness of the ejecta. The observed degree of polarization of the Type Ic SN 1997X is above 5%. The data reveal a trend that the degree of polarization increases with decreasing envelope mass and with the depth within the ejecta. We speculate that Type IIB, Type Ib, and Type Ic may be very similar events viewed from different aspect angles. The high axial ratio of the ejecta is difficult to explain in terms of the conventional neutrino driven core-collapse models for Type II explosions. Highly asymmetric explosion mechanisms such as the formation of bipolar jets during core-collapse may be a necessary ingredient for models of all core-collapse supernovae.

Lifan Wang; D. Andrew Howell; Peter Hoeflich; J. Craig Wheeler

1999-12-01

409

Electrodeionization Using Microseparated Bipolar Membranes  

NASA Technical Reports Server (NTRS)

An electrochemical technique for deionizing water, now under development, is intended to overcome a major limitation of prior electrically-based water-purification techniques. The limitation in question is caused by the desired decrease in the concentration of ions during purification: As the concentration of ions decreases, the electrical resistivity of the water increases, posing an electrical barrier to the removal of the remaining ions. In the present technique, this limitation is overcome by use of electrodes, a flowfield structure, and solid electrolytes configured to provide conductive paths for the removal of ions from the water to be deionized, even when the water has already been purified to a high degree. The technique involves the use of a bipolar membrane unit (BMU), which includes a cation-exchange membrane and an anion-exchange membrane separated by a nonconductive mesh that has been coated by an ionically conductive material (see figure). The mesh ensures the desired microseparation between the ion-exchange membranes: The interstices bounded by the inner surfaces of the membranes and the outer surfaces of the coated mesh constitute a flow-field structure that allows the water that one seeks to deionize (hereafter called "process water" for short) to flow through the BMU with a low pressure drop. The flow-field structure is such that the distance between any point in the flow field and an ionically conductive material is small; thus, the flow-field structure facilitates the diffusion of molecules and ions to and from the ion-exchange membranes. The BMU is placed between an anode and a cathode, but not in direct contact with these electrodes. Instead, the space between the anion-exchange membrane and the anode is denoted the anode compartment and is filled with an ionic solution. Similarly, the space between the cation-exchange membrane and the cathode is denoted the cathode compartment and is filled with a different ionic solution. The electrodes are made of titanium coated with platinum.

Lyons, Donald; Jackson, George; Andrews, Craig C.; Tennakoon, Charles L, K.; Singh, Waheguru; Hitchens, G. Duncan; Jabs, Harry; Chepin, James F.; Archer, Shivaun; Gonzalez-Martinez, Anukia; Cisar, Alan J.

2004-01-01

410

Current issues in bipolar disorder: A critical review  

Microsoft Academic Search

Although awareness on bipolar disorder has increased during the last decade, this condition remains characterized by a disabling burden, in terms of morbidity and functional impairment. This paper aims to review some critical issues in the current knowledge on Bipolar disorder. Although large European epidemiological studies are lacking, Bipolar disorder is characterized by a set of severe features, including an

Pierre Oswald; Daniel Souery; Siegfried Kasper; Yves Lecrubier; Stuart Montgomery; Sabien Wyckaert; Joseph Zohar; Julien Mendlewicz

2007-01-01

411

Basal ganglia and thalamic morphology in schizophrenia and bipolar disorder  

E-print Network

Basal ganglia and thalamic morphology in schizophrenia and bipolar disorder Fay Y. Womer a,n , Lei of the basal ganglia and thalamus in bipolar disorder (BP), schizophrenia-spectrum disorders (SCZ in neuroimaging studies. & 2014 Elsevier Ireland Ltd. All rights reserved. 1. Introduction Differentiating bipolar

412

Personalised Ambient Monitoring (PAM) for people with Bipolar Disorder  

E-print Network

Personalised Ambient Monitoring (PAM) for people with Bipolar Disorder P Prociow1 , J.A. Crowe1 , S of a monitoring system for patients with bipolar disorder containing environmental and wearable sensors. Introduction Almost 2% of the UK population have bipolar disorder, a group who, in their lifetime

Magill, Evan H.

413

Choosing How to Feel: Emotion Regulation Choice in Bipolar Disorder  

E-print Network

Emotion Choosing How to Feel: Emotion Regulation Choice in Bipolar Disorder Aleena C. Hay, Gal How to Feel: Emotion Regulation Choice in Bipolar Disorder. Emotion. Advance online publication. http June Gruber University of Colorado Boulder Individuals with bipolar disorder experience emotion

Gross, James J.

414

Corpus Callosum Morphology in Twin Pairs Discordant for Bipolar Disorder  

E-print Network

Corpus Callosum Morphology in Twin Pairs Discordant for Bipolar Disorder Submission No: 3973 callosal volume reduction in patients with bipolar disorder, but it is not yet known whether these deficits callosum (CC) thickness and curvature in a population-based sample of twin pairs discordant for bipolar

Thompson, Paul

415

Brain Magnetic Resonance Imaging of Structural Abnormalities in Bipolar Disorder  

Microsoft Academic Search

Background: The neuropathogenesis of bipolar disor- der remains poorly described. Previous work suggests that patients with bipolar disorder may have abnormalities in neural pathways that are hypothesized to modulate hu- man mood states. We examined differences in brain struc- tural volumes associated with these pathways between patients with bipolar disorder hospitalized with mania and healthy community volunteers. Methods: Twenty-four patients

Stephen M. Strakowski; Melissa P. DelBello; Kenji W. Sax; Molly E. Zimmerman; Paula K. Shear; John M. Hawkins; Eric R. Larson

1999-01-01

416

CASE REPORT Open Access A bipolar disorder patient becoming  

E-print Network

CASE REPORT Open Access A bipolar disorder patient becoming asymptomatic after adjunctive anti be involved in bipolar disorder. So far, few have been written for the association between parasitic infection and bipolar disorder. Filariasis is a parasitic disease acting ruthlessly via mosquitos and affecting more

Paris-Sud XI, Université de

417

Family Functioning and the Course of Adolescent Bipolar Disorder  

ERIC Educational Resources Information Center

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,…

Sullivan, Aimee E.; Judd, Charles M.; Axelson, David A.; Miklowitz, David J.

2012-01-01

418

IMMEDIATE COMMUNICATION Whole-genome association study of bipolar disorder  

E-print Network

IMMEDIATE COMMUNICATION Whole-genome association study of bipolar disorder P Sklar1,2,3,4 , JW, London, UK We performed a genome-wide association scan in 1461 patients with bipolar (BP) 1 disorder, 2008 controls drawn from the Systematic Treatment Enhancement Program for Bipolar Disorder

de Bakker, Paul

419

Omega3 fatty acids and bipolar disorder: a review  

Microsoft Academic Search

The important role of the omega-3 fatty acids in the pathophysiology and treatment of bipolar disorder is now supported by a substantial body of indirect and direct evidence. This paper will describe the clinical and pharmacological features of bipolar disorder, review the available data regarding omega-3 fatty acids in bipolar disorder and provide recommendations for future research.

A. L. Stoll; C. A. Locke; L. B. Marangell; W. E. Severus

1999-01-01

420

Pharmacotherapy of depression and mixed states in bipolar disorder  

Microsoft Academic Search

The treatment of bipolar depression requires the resolution of depression and the establishment of mood stability. A basic problem is that the treatments used in treating bipolar depression were developed and proven effective for other disease states: antidepressants for unipolar depression, and mood stabilizers for mania. The panel addressed four unresolved questions regarding depression in relation to bipolar disorder: (1)

Stuart A Montgomery; Alan F Schatzberg; J. D Guelfi; Siegfried Kasper; Charles Nemeroff; Alan Swann; John Zajecka

2000-01-01

421

Nitrided Metallic Bipolar Plates M.P. Brady (project lead)  

E-print Network

Nitrided Metallic Bipolar Plates M.P. Brady (project lead) P. F. Tortorelli Oak Ridge National: Surface Treatment to Protect Stamped Metallic Bipolar Plates Overall Goal: Demonstrate potential for metallic bipolar plates to meet 5000 h automotive durability goal at cost

422

Electrodialytic remediation of copper mine tailings using bipolar electrodes  

Microsoft Academic Search

In this work an electrodialytic remediation (EDR) cell for copper mine tailings with bipolar stainless steel plates was analyzed. The bipolar plates were inserted inside the tailings, dividing it into independent electrochemical cells or sections, in order to increase the copper removal efficiency from mine tailings. The bipolar plates design was tested on acidic copper mine tailings with a fixed:

Adrián Rojo; Luis Cubillos

2009-01-01

423

Performance of PEMFC stack using expanded graphite bipolar plates  

Microsoft Academic Search

The bipolar plates are in weight and volume the major part of PEM fuel cell stack, and also a significant effect to the stack cost. To develop the low-cost and low-weight bipolar plate for PEM fuel cell, we have developed a kind of cheap expanded graphite plate material and a production process for fuel cell bipolar plates. The plates have

Xiqiang Yan; Ming Hou; Haifeng Zhang; Fenning Jing; Pingwen Ming; Baolian Yi

2006-01-01

424

Bipolar plate materials for solid polymer fuel cells  

Microsoft Academic Search

The interfacial ohmic losses between the bipolar plate and the MEA can significantly reduce the overall power output from a SPFC. For graphitic bipolar plate materials, these losses are insignificant relative to stainless steel, where the existence of a passive film on the surface greatly reduces electrical conductivity. In this paper we have evaluated different bipolar plate materials, and present

D. P. Davies; P. L. Adcock; M. Turpin; S. J. Rowen

2000-01-01

425

Bipolar SQLf: a Flexible Querying Language for Relational Databases  

E-print Network

on fuzzy bipolar conditions in which the constraint and the wish are defined by fuzzy sets. Furthermore, we bipolar conditions of the SQLf language [2, 1] which is devoted to flexible querying with fuzzy sets allows expressing complex preferences in user queries. Such preferences can be modeled by fuzzy bipolar

Paris-Sud XI, Université de

426

Small scale bipolar nickel-hydrogen testing  

NASA Technical Reports Server (NTRS)

Bipolar nickel-hydrogen batteries, ranging in capacity from 6 to 40 A-hr, have been tested at the NASA Lewis Research Center over the past six years. Small scale tests of 1 A-hr nickel-hydrogen stacks have been initiated as a means of screening design and component variations for bipolar nickel-hydrogen cells and batteries. Four small-scale batteries have been built and tested. Characterization and limited cycle testing were performed to establish the validity of test results in the scaled down hardware. The results show characterization test results to be valid. LEO test results in the small scale hardware have limited value.

Manzo, Michelle A.

1988-01-01

427

Bipolar Fuzzy Mathematical Morphology for Spatial Reasoning  

NASA Astrophysics Data System (ADS)

Bipolarity is an important feature of spatial information, involved in the expressions of preferences and constraints about spatial positioning, or in pairs of “opposite” spatial relations such as left and right. Imprecision should also be taken into account, and fuzzy sets is then an appropriate formalism. In this paper, we propose to handle such information based on mathematical morphology operators, extended to the case of bipolar fuzzy sets. The potential of this formalism for spatial reasoning is illustrated on a simple example in brain imaging.

Bloch, Isabelle

428

Field Dependent Dopant Deactivation in Bipolar Devices at Elevated irradiation Temperatures  

SciTech Connect

Metal-oxide-silicon capacitors fabricated in a bi-polar process were examined for densities of oxide trapped charge, interface traps and deactivated substrate acceptors following high-dose-rate irradiation at 100 C. Acceptor neutralization near the Si surface occurs most efficiently for small irradiation biases in depletion. The bias dependence is consistent with compensation and passivation mechanisms involving the drift of H{sup +} ions in the oxide and Si layers and the availability of holes in the Si depletion region. Capacitor data from unbiased irradiations were used to simulate the impact of acceptor neutralization on the current gain of an npn bipolar transistor. Neutralized acceptors near the base surface enhance current gain degradation associated with radiation-induced oxide trapped charge and interface traps by increasing base recombination. The additional recombination results from the convergence of carrier concentrations in the base and increased sensitivity of the base to oxide trapped charge. The enhanced gain degradation is moderated by increased electron injection from the emitter. These results suggest that acceptor neutralization may enhance radiation-induced degradation of linear circuits at elevated temperatures.

WITCZAK,STEVEN C.; LACOE,RONALD C.; SHANEYFELT,MARTY R.; MAYER,DONALD C.; SCHWANK,JAMES R.; WINOKUR,PETER S.

2000-08-15

429

Single Mesowire Transistor From Perylene Tetracarboxylic Diimide  

Microsoft Academic Search

We have recently fabricated new nano\\/mesowires of perylene tetracarboxylic diimide (PTCDI) without side chains by self-assembling them from a gas phase. In this letter, we discuss a single PTCDI mesowire transistor that was successfully fabricated, characterized, and modeled. This organic n-channel field effect transistor shows good output and transfer characteristics. Our transistor model includes the Poole–Frenkel electric field dependence of

Mark A. Koorie; Yashdeep Khopkar; Hai-Feng Ji; Sandra R. Zivanovic

2012-01-01

430

Coaxial inverted geometry transistor having buried emitter  

NASA Technical Reports Server (NTRS)

The invention relates to an inverted geometry transistor wherein the emitter is buried within the substrate. The transistor can be fabricated as a part of a monolithic integrated circuit and is particularly suited for use in applications where it is desired to employ low actuating voltages. The transistor may employ the same doping levels in the collector and emitter, so these connections can be reversed.

Hruby, R. J.; Cress, S. B.; Dunn, W. R. (inventors)

1973-01-01

431

Displacement Damage in Bipolar Linear Integrated Circuits  

NASA Technical Reports Server (NTRS)

Although many different processes can be used to manufacture linear integrated circuits, the process that is used for most circuits is optimized for high voltage -- a total power supply voltage of about 40 V -- and low cost. This process, which has changed little during the last twenty years, uses lateral and substrate p-n-p transistors. These p-n-p transistors have very wide base regions, increasing their sensitivity to displacement damage from electrons and protons. Although displacement damage effects can be easily treated for individual transistors, the net effect on linear circuits can be far more complex because circuit operation often depends on the interaction of several internal transistors. Note also that some circuits are made with more advanced processes with much narrower base widths. Devices fabricated with these newer processes are not expected to be significantly affected by displacement damage for proton fluences below 1 x 10(exp 12) p/sq cm. This paper discusses displacement damage in linear integrated circuits with more complex failure modes than those exhibited by simpler devices, such as the LM111 comparator, where the dominant response mode is gain degradation of the input transistor. Some circuits fail catastrophically at much lower equivalent total dose levels compared to tests with gamma rays. The device works satisfactorily up to nearly 1 Mrad(Si) when it is irradiated with gamma rays, but fails catastrophically between 50 and 70 krad(Si) when it is irradiated with protons.

Rax, B. G.; Johnston, A. H.; Miyahira, T.

2000-01-01

432

Thermally induced current bifurcation in bipolar transistors L. La Spina a,*, N. Nenadovic a,1  

E-print Network

, P.O. Box 5053, 2628 CT Delft, The Netherlands b Department of Electronics and Telecommunications Engineering, University of Naples Federico II, Via Claudio 21, 80125 Naples, Italy Received 23 February 2006

Technische Universiteit Delft

433

A heterojunction bipolar transistor with stepwise allog-graded base : analysis, design, fabrication, and characterization  

E-print Network

(cont.) features but the device self-heating turned out to be crucial for the longevity of the base micro-airbridges. The short lifetime of the base micro-airbridges was prohibitive for the realization of high frequency ...

Konistis, Konstantinos, 1973-

2004-01-01

434

Parasitic capacitance extraction in bipolar junction transistor for arbitrarily shaped diffusion  

E-print Network

)] + czn n(n ? 1) i=i 32 4 1 5 7 2 I 6 3 8 9 LEVEL I PARTITION V 4 3 1 2 I 5 7 6 4 8 9 LPvEL 1 3 2 2 V 3 5 7 6 4 8 9 V=7 5 6 4 7 8 9 LrvEI. 3 V 1 DOE E 5 4 6 7 8 9 V-8 LEVPS. 4 DOKE IXIKE V = 6 IXLRE V = 9 PhA IXINE DORT: DONE DOKE... Super Polygon Outer Polygon Dl D2 D3 D4 Dl D2 D3 D4 D5 D6 D7 D8 DI D2 D3 D4 D5 D6 D7 D8 D9 Format Innner Polygon El E2 E 3 E4 El E2 E 3 E4 Theorem 1. If two po]ygons share s. common point then the union of these polygons is a super polygon...

Hassan, Mehedi

1992-01-01

435

Minority carrier transport properties of GaInNAs heterojunction bipolar transistors with 2% nitrogen  

E-print Network

% nitrogen Rebecca J. Welty,a) Huoping Xin, Charles W. Tu, and Peter M. Asbeck University of California) of 0.98 eV; this is achieved with a nitrogen composition of 2%. These devices have a turn-on voltage HFE is 8. The current gain of nitrogen containing HBTs is degraded due to the complex change

Asbeck, Peter M.

436

JANTX2N2369A transistor  

NASA Technical Reports Server (NTRS)

Report describes effects of power and temperature overstress on National Semiconductor and Raytheon transistors. Good junction quality was maintained. Gain losses predominated. Other failures are reported.

1980-01-01

437

Panel fabrication utilizing GaAs solar cells  

NASA Technical Reports Server (NTRS)

The development of the GaAs solar cells for space applications is described. The activities in the fabrication of GaAs solar panels are outlined. Panels were fabricated while introducing improved quality control, soldering laydown and testing procedures. These panels include LIPS II, San Marco Satellite, and a low concentration panel for Rockwells' evaluation. The panels and their present status are discussed.

Mardesich, N.

1984-01-01

438

Transistor oscillator and amplifier grids  

Microsoft Academic Search

Although quasi-optical techniques are applicable to a large variety of solid-state devices, special attention is given to transistors, which are attractive because they can be used as either amplifiers or oscillators. Experimental results for MESFET bar-grid and planar grid oscillators are presented. A MESFET grid amplifier that receives only vertically polarized waves at the input and radiates horizontally polarized waves

ROBERT M. WEIKLE; MOONIL KIM; JONATHAN B. HACKER; MICHAEL P. DE LISIO; ZOYA B. POPOVIC; DAVID B. RUTLEDGE

1992-01-01

439

John Bardeen and transistor physics  

Microsoft Academic Search

John Bardeen and Walter Brattain invented the point-contact semiconductor amplifier (transistor action) in polycrystalline germanium (also observed in polycrystalline silicon) on Dec. 15, 1947, for which they received a patent on Oct. 3, 1950. Bill Shockley was not a co-patent holder on Bardeen and Brattain's point-contact semiconductor amplifier patent since Julius Lilienfeld had already received a patent in 1930 for

Howard R. Huff

2001-01-01

440

John Bardeen and transistor physics  

Microsoft Academic Search

John Bardeen and Walter Brattain invented the point-contact semiconductor amplifier (transistor action) in polycrystalline germanium (also observed in polycrystalline silicon) on Dec. 15, 1947, for which they received a patent on Oct. 3, 1950. Bill Shockley was not a co-patent holder on Bardeen and Brattain’s point-contact semiconductor amplifier patent since Julius Lilienfeld had already received a patent in 1930 for

Howard R. Huff

2001-01-01

441

PNPN latchup in bipolar LSI devices. Final report, 1 January 1980-1 October 1981  

SciTech Connect

PNPN latchup was studied both analytically and experimentally in several bipolar LSI technologies including integrated injection logic (I to the second power L), integrated Schottky logic (ISL), Schottky Transistor logic (STL) and emitter coupled logic (ECL). The latchup analysis procedure was expanded and applied to LSI microcircuits representing each of the technologies. This procedure consists of a) the identification of parasitic PNPN paths, b) the electrical characterization of the paths, c) detailed circuit analysis, and d) determination of worst case bias conditions for radiation testing. The identification was performed from chip photomicrographs and composite mask drawings. The characterization was performed experimentally by measuring parasitic transistor gains and SCR parameters on decoupled paths and analytically by using a semiconductor device physics code (PN code) in conjunction with doping profiles. The detailed circuit analysis was performed either by hand or with the circuit analysis code SPICE. Radiation testing was performed at the White Sands Missile Range LINAC facility. The results of the study were, a) latchup cannot occur in non-isolated I to the second power L, b) latchup cannot occur in the internal logic of ISL or STL without causing a problem with electrical performance, c) no latchable paths were found by analysis in the 93471 ECL 4kK RAM, the I/0 buffers on a ISL/STL gate array or the I to the second power L peripherals of the 9408 I to the 3rd power L microprogram sequencer.

Pease, R.L.; Alexander, D.R.

1982-01-01

442

A single-atom transistor.  

PubMed

The ability to control matter at the atomic scale and build devices with atomic precision is central to nanotechnology. The scanning tunnelling microscope can manipulate individual atoms and molecules on surfaces, but the manipulation of silicon to make atomic-scale logic circuits has been hampered by the covalent nature of its bonds. Resist-based strategies have allowed the formation of atomic-scale structures on silicon surfaces, but the fabrication of working devices-such as transistors with extremely short gate lengths, spin-based quantum computers and solitary dopant optoelectronic devices-requires the ability to position individual atoms in a silicon crystal with atomic precision. Here, we use a combination of scanning tunnelling microscopy and hydrogen-resist lithography to demonstrate a single-atom transistor in which an individual phosphorus dopant atom has been deterministically placed within an epitaxial silicon device architecture with a spatial accuracy of one lattice site. The transistor operates at liquid helium temperatures, and millikelvin electron transport measurements confirm the presence of discrete quantum levels in the energy spectrum of the phosphorus atom. We find a charging energy that is close to the bulk value, previously only observed by optical spectroscopy. PMID:22343383

Fuechsle, Martin; Miwa, Jill A; Mahapatra, Suddhasatta; Ryu, Hoon; Lee, Sunhee; Warschkow, Oliver; Hollenberg, Lloyd C L; Klimeck, Gerhard; Simmons, Michelle Y

2012-04-01

443

Yinyang Bipolar Fuzzy Sets and Fuzzy Equilibrium Relations: for Clustering, Optimization, and Global Regulation  

Microsoft Academic Search

Based on the notions of bipolar lattices and L-sets, YinYang bipolar fuzzy sets and fuzzy equilibrium relations are presented for bipolar clustering, optimization, and global regulation. While a bipolar L-set is defined as a bipolar equilibrium function L that maps a bipolar object set X over an arbitrary bipolar lattice B as L:X ? B, this work focuses on the

Wen-ran Zhang

2006-01-01

444

Lightweight bipolar metal-gas battery  

Microsoft Academic Search

This patent describes a bipolar metal-gas battery cell stack. The battery is composed of several electrically series-connected stacked cells each having one negative electrode and one positive electrode, wherein series electrical connections between oppositely polarized electrodes of adjacent cells are made external to the cells; means for confining electrolyte within each cell; and means for confining overcharged gasses within each

G. Van Ommering; C. W. Koehler

1986-01-01

445

Neuropsychology of bipolar disorder: a review  

Microsoft Academic Search

Background: Bipolar disorder (BD) may be associated with significant and persistent cognitive impairment. The aim of this study was to describe the profile of cognitive deficits in BD at different phases of the illness and determine whether it is different from that of schizophrenia and unipolar (UP) depression. Methods: A systematic review of the computerised literature of neuropsychological studies of

Seema Quraishi; Sophia Frangou

2002-01-01

446

Regulation of ON Bipolar Cell Activity  

PubMed Central

Synaptic transmission from photoreceptors to all types of ON bipolar cells is primarily mediated by the mGluR6 receptor. This receptor, which is apparently expressed uniquely in the nervous system by ON bipolar cells, couples negatively to a nonselective cation channel. This arrangement results in a sign reversal at photoreceptor/ON bipolar cell synapse, which is necessary in order to establish parallel ON and OFF pathways in the retina. The synapse is an important target for 2nd messenger molecules that are known to modulate synaptic transmission elsewhere in the nervous system, 2nd messengers that act on a time scale ranging from milliseconds to minutes. This review focuses on two of these molecules, Ca2+ and cGMP, summarizing our current knowledge of how they modulate gain at the photoreceptor/ON bipolar cell synapse, as well as their proposed sites of action within the mGluR6 cascade. The implications of plasticity at this synapse for retinal function will also be examined. PMID:18524666

Snellman, Josefin; Kaur, Tejinder; Shen, Yin; Nawy, Scott

2008-01-01

447

Bipolar Diffusion Charging of Soot Aggregates  

Microsoft Academic Search

Experimental measurements of bipolar diffusion charging efficiency over the range of 15–400 nm are compared for oil droplets, flame generated soot aggregates, and diesel engine exhaust particulate matter to explore possible effects of particle morphology. Charging efficiency is recorded using a tandem differential mobility analyzer (DMA) approach; the first DMA selects a monodisperse aerosol and the second compares the flux

M. Matti Maricq

2008-01-01

448

Titanium carbide bipolar plate for electrochemical devices  

DOEpatents

A corrosion resistant, electrically conductive, non-porous bipolar plate is made from titanium carbide for use in an eletrochemical device. The process involves blending titanium carbide powder with a suitable binder material, and molding the mixture, at an elevated temperature and pressure.

LaConti, Anthony B. (Lynnfield, MA); Griffith, Arthur E. (Lynn, MA); Cropley, Cecelia C. (Acton, MA); Kosek, John A. (Danvers, MA)

2000-07-04

449

A Review of Bipolar Disorder in Adults  

PubMed Central

Objective: This article reviews the epidemiology, etiology, assessment, and management of bipolar disorder. Special attention is paid to factors that complicate treatment, including nonadherence, comorbid disorders, mixed mania, and depression. Methods: A Medline search was conducted from January of 1990 through December of 2005 using key terms of bipolar disorder, diagnosis, and treatment. Papers selected for further review included those published in English in peer-reviewed journals, with preference for articles based on randomized, controlled trials and consensus guidelines. Citations de-emphasized original mania trials as these are generally well known. Results: Bipolar disorder is a major public health problem, with diagnosis often occurring years after onset of the disorder. comorbid conditions are common and difficult to treat. Management includes a lifetime course of medication, usually more than one, and attention to psychosocial issues for patients and their families. Management of mania is well-established. Research is increasing regarding management of depressive, mixed and cycling episodes, as well as combination therapy. Conclusions: Bipolar disorder is a complex psychiatric disorder to manage, even for psychiatrists, because of its many episodes and comorbid disorders and nonadherence to treatment. PMID:20975827

Leamon, Martin H.; Lim, Russell F.; Kelly, Rosemary H.; Hales, Robert E.

2006-01-01

450

Metallic bipolar plates for PEM fuel cells  

Microsoft Academic Search

Metallic bipolar plates for Polymer electrolyte membrane (PEM) fuel cells with and without coatings were tested in single cell tests. Current–voltage curves, lifetime curves and the contamination with metal ions were measured. Additionally the surface of the plates was analyzed by several methods. So far the investigations revealed that principally stainless steel covered with a thin coating is suitable as

J Wind; R Späh; W Kaiser; G Böhm

2002-01-01

451

Titanium Carbide Bipolar Plate for Electrochemical Devices  

SciTech Connect

Titanium carbide comprises a corrosion resistant, electrically conductive, non-porous bipolar plate for use in an electrochemical device. The process involves blending titanium carbide powder with a suitable binder material, and molding the mixture, at an elevated temperature and pressure.

LaConti, Anthony B.; Griffith, Arthur E.; Cropley, Cecelia C.; Kosek, John A.

1998-05-08

452

Brazed bipolar plates for PEM fuel cells  

DOEpatents

A liquid-cooled, bipolar plate separating adjacent cells of a PEM fuel cell comprising corrosion-resistant metal sheets brazed together so as to provide a passage between the sheets through which a dielectric coolant flows. The brazement comprises a metal which is substantially insoluble in the coolant.

Neutzler, Jay Kevin (Rochester, NY)

1998-01-01

453

Brazed bipolar plates for PEM fuel cells  

DOEpatents

A liquid-cooled, bipolar plate separating adjacent cells of a PEM fuel cell comprises corrosion-resistant metal sheets brazed together so as to provide a passage between the sheets through which a dielectric coolant flows. The brazement comprises a metal which is substantially insoluble in the coolant. 6 figs.

Neutzler, J.K.

1998-07-07

454

Bipolar disorder: Evidence for a major locus  

SciTech Connect

Complex segregation analyses were conducted on families of bipolar I and bipolar II probands to delineate the mode of inheritance. The probands were ascertained from consecutive referrals to the Mood Disorder Service, University Hospital, University of British Columbia and diagnosed by DSM-III-R and Research Diagnostic Criteria. Data were available on over 1,500 first-degree relatives of the 186 Caucasian probands. The purpose of the analyses was to determine if, after correcting for age and birth cohort, there was evidence for a single major locus. Five models were fit to the data using the statistical package SAGE: (1) dominant, (2) recessive, (3) arbitrary mendelian inheritance, (4) environmental, and (5) no major effects. A single dominant, mendelian major locus was the best fitting of these models for the sample of bipolar I and II probands when only bipolar relatives were defined as affected (polygenic inheritance could not be tested). Adding recurrent major depression to the diagnosis {open_quotes}affected{close_quotes} for relatives reduced the evidence for a major locus effect. Our findings support the undertaking of linkage studies and are consistent with the analyses of the National Institutes of Mental Health (NIMH) Collaborative Study data by Rice et al. and Blangero and Elston. 39 refs., 4 tabs.

Spence, M.A.; Flodman, P.L. [Univ. of California, Irvine, CA (United States); Sadovnick, A.D.; Ameli, H. [Univ. of British Columbia, Vancouver (Canada)] [and others

1995-10-09

455

Sealed bipolar multi-cell battery  

Microsoft Academic Search

A low maintenance battery comprises a sealed casing having a cavity receiving a stack of monopolar and bipolar plates interspersed with mats of fiberglass felt immobilizing electrolyte and forming a gas path for diffusion of oxygen to the negative electrode. The casing contains a single, resealable vent. During charging, oxygen generated at the positive plate diffuses through the mat and

Rowlette

1985-01-01

456

Bipolar battery with array of sealed cells  

Microsoft Academic Search

A bipolar battery is described comprising individual cells with electrode faces in a face-to-face stacked array with electrically opposite electrode ends and electrically conductive end face caps in contact with the electrode ends of the array, each cell including a pair of electrically opposite electrodes in contact with and separated by a central separator containing an electrolyte normally fluid during

T. D. Kaun; J. A. Smaga

1987-01-01

457

A bipolar model of assertability and belief  

Microsoft Academic Search

Valuation pairs are introduced as a bipolar model of the assertability of propositions. These correspond to a pair of dual valuation functions, respectively, representing the strong property of definite assertability and the dual weaker property of acceptable assertability. In the case where there is uncertainty about the correct valuation pair for a language then a probability distribution is defined on

Jonathan Lawry; Inés González-Rodríguez

2011-01-01

458

Bipolar Queries and Queries with Preferences  

Microsoft Academic Search

The concepts of bipolar queries and queries with preferences are studied. Various interpretations of the former, recently defined by Dubois and Prade, are discussed. The latter was defined by Chomicki together with a new relational algebra operator winnow. The fuzzy version of the winnow operator is proposed. It is shown how it may be used to express a selected interpretation

Slawomir Zadrozny; Janusz Kacprzyk

2006-01-01

459

Bipolar queries: An aggregation operator focused perspective  

Microsoft Academic Search

The concept of a bipolar query, meant as a database query that involves both negative and positive conditions, is discussed from the point of view of flexible database querying and modeling of more sophisticated intentions and preferences of the user. The aggregation of matching degrees against the negative and positive conditions to derive an overall matching degree is considered taking

S?awomir Zadro?ny; Janusz Kacprzyk

460

A low-power-dissipation broadband cryogenic preamplifier utilizing GaAs MESFETs in parallel  

SciTech Connect

A voltage sensitive preamplifier design is presented for operation at 1.6 K. The active device is a Sony 3SK164 dual-gate GaAs metal-semiconductor field-effect transistor (MESFET), which was chosen for its low-frequency noise performance, stability against oscillations, and the inclusion of a gate protection diode. Active devices made from GaAs operate at cryogenic temperatures without carrier freeze out.'' The main design goal was to keep the power dissipation in the cryostat minimal, while maintaining high bandwidth and low noise. This was achieved by operating four parallel MESFETs at cryogenic temperatures in cascode with a room-temperature Si JFET. Parallel operation gives a higher transconductance-to-power dissipation ratio than with a single device. The input cascode is followed by high-speed, low-noise operational amplifiers. The low-frequency noise corner occurs at 100 kHz. The white voltage noise of the preamplifier referred to the input is [lt]0.9 nV/Hz[sup 1/2] at 1 MHz with 2 mW dissipated in the cryogenic stage. The power dissipation can be reduced to 1 mW with a moderate increase in noise. The preamplifier noise was found to be dominated by the cryogenic stage. There are two 50-[Omega] outputs with gains of 39 dB and 59 dB, and the [minus]3 dB points occur at 500 Hz and 10 MHz. The design of the preamplifier is discussed in detail. Noise measurements under a variety of bias conditions are presented along with an analysis of the different noise sources.

Lee, A.T. (Physics Department, Stanford University, Stanford, California 94305 (United States))

1993-08-01

461

Multigate transistors as the future of classical metal-oxide-semiconductor field-effect transistors.  

PubMed

For more than four decades, transistors have been shrinking exponentially in size, and therefore the number of transistors in a single microelectronic chip has been increasing exponentially. Such an increase in packing density was made possible by continually shrinking the metal-oxide-semiconductor field-effect transistor (MOSFET). In the current generation of transistors, the transistor dimensions have shrunk to such an extent that the electrical characteristics of the device can be markedly degraded, making it unlikely that the exponential decrease in transistor size can continue. Recently, however, a new generation of MOSFETs, called multigate transistors, has emerged, and this multigate geometry will allow the continuing enhancement of computer performance into the next decade. PMID:22094690

Ferain, Isabelle; Colinge, Cynthia A; Colinge, Jean-Pierre

2011-11-17

462

Memantine: New prospective in bipolar disorder treatment  

PubMed Central

We review preclinical and clinical evidences strongly suggesting that memantine, an old drug currently approved for Alzheimer’s dementia, is an effective treatment for acute mania and for the prevention of manic/hypomanic and depressive recurrences of manic-depressive illness. Lithium remains the first line for the treatment and prophylaxis of bipolar disorders, but currently available treatment alternatives for lithium resistant patients are of limited and/or questionable efficacy. Thus, research and development of more effective mood stabilizer drugs is a leading challenge for modern psychopharmacology. We have demonstrated that 21 d administration of imipramine causes a behavioural syndrome similar to a cycle of bipolar disorder, i.e., a mania followed by a depression, in rats. Indeed, such treatment causes a behavioural supersensitivity to dopamine D2 receptor agonists associated with an increase sexual activity and aggressivity (mania). The dopamine receptor sensitization is followed, after imipramine discontinuation, by an opposite phenomenon (dopamine receptor desensitization) and an increased immobility time (depression) in the forced swimming test of depression. Memantine blocks the development of the supersensitivity and the ensuing desensitization associated with the depressive like behavior. On the basis of these observations we have suggested the use of memantine in the treatment of mania and in the prophylaxis of bipolar disorders. To test this hypothesis we performed several naturalistic studies that showed an acute antimanic effect and a long-lasting and progressive mood-stabilizing action (at least 3 years), without clinically relevant side effects. To confirm the observations of our naturalistic trials we are now performing a randomized controlled clinical trial. Finally we described the studies reporting the efficacy of memantine in manic-like symptoms occurring in psychiatric disorders other than bipolar. Limitations: A randomized controlled clinical trial is needed to confirm our naturalistic observations. Conclusion: We believe that this review presents enough pharmacological and clinical information to consider the administration of memantine in the treatment of bipolar disorders that no respond to standard mood stabilizers.

Serra, Giulia; Demontis, Francesca; Serra, Francesca; De Chiara, Lavinia; Spoto, Andrea; Girardi, Paolo; Vidotto, Giulio; Serra, Gino

2014-01-01

463

Reproducible bipolar resistive switching in entire nitride AlN/n-GaN metal-insulator-semiconductor device and its mechanism  

NASA Astrophysics Data System (ADS)

Reproducible bipolar resistive switching characteristics are demonstrated in entire nitride AlN/n-GaN metal-insulator-semiconductor devices. The mechanism involved confirms to trap-controlled space charge limited current theory and can be attributed to the nitrogen vacancies of AlN serving as electron traps that form/rupture electron transport channel by trapping/detrapping electrons. This study will lead to the development of in-situ growth of group-III nitrides by metal-organic chemical vapor deposition as a candidate for next-generation nonvolatile memory device. Moreover, it will be benefit to structure monolithic integrated one-transistor-one-resistor memory with nitride high electron mobility transistors.

Chen, Yiren; Song, Hang; Jiang, Hong; Li, Zhiming; Zhang, Zhiwei; Sun, Xiaojuan; Li, Dabing; Miao, Guoqing

2014-11-01

464

SEMICONDUCTOR DEVICES: Structural and electrical characteristics of lanthanum oxide gate dielectric film on GaAs pHEMT technology  

NASA Astrophysics Data System (ADS)

This paper investigates the feasibility of using a lanthanum oxide thin film (La2O3) with a high dielectric constant as a gate dielectric on GaAs pHEMTs to reduce gate leakage current and improve the gate to drain breakdown voltage relative to the conventional GaAs pHEMT. An E/D mode pHEMT in a single chip was realized by selecting the appropriate La2O3 thickness. The thin La2O3 film was characterized: its chemical composition and crystalline structure were determined by X-ray photoelectron spectroscopy and X-ray diffraction, respectively. La2O3 exhibited good thermal stability after post-deposition annealing at 200, 400 and 600 °C because of its high binding-energy (835.6 eV). Experimental results clearly demonstrated that the La2O3 thin film was thermally stable. The DC and RF characteristics of Pt/La2O3/Ti/Au gate and conventional Pt/Ti/Au gate pHEMTs were examined. The measurements indicated that the transistor with the Pt/La2O3/Ti/Au gate had a higher breakdown voltage and lower gate leakage current. Accordingly, the La2O3 thin film is a potential high-k material for use as a gate dielectric to improve electrical performance and the thermal effect in high-power applications.

Chia-Song, Wu; Hsing-Chung, Liu

2009-11-01

465

Electronic properties of GaAs, InAs and InP nanowires studied by terahertz spectroscopy.  

PubMed

We have performed a comparative study of ultrafast charge carrier dynamics in a range of III-V nanowires using optical pump-terahertz probe spectroscopy. This versatile technique allows measurement of important parameters for device applications, including carrier lifetimes, surface recombination velocities, carrier mobilities and donor doping levels. GaAs, InAs and InP nanowires of varying diameters were measured. For all samples, the electronic response was dominated by a pronounced surface plasmon mode. Of the three nanowire materials, InAs nanowires exhibited the highest electron mobilities of 6000 cm² V?¹ s?¹, which highlights their potential for high mobility applications, such as field effect transistors. InP nanowires exhibited the longest carrier lifetimes and the lowest surface recombination velocity of 170 cm s?¹. This very low surface recombination velocity makes InP nanowires suitable for applications where carrier lifetime is crucial, such as in photovoltaics. In contrast, the carrier lifetimes in GaAs nanowires were extremely short, of the order of picoseconds, due to the high surface recombination velocity, which was measured as 5.4 × 10?? cm s?¹. These findings will assist in the choice of nanowires for different applications, and identify the challenges in producing nanowires suitable for future electronic and optoelectronic devices. PMID:23619012

Joyce, Hannah J; Docherty, Callum J; Gao, Qiang; Tan, H Hoe; Jagadish, Chennupati; Lloyd-Hughes, James; Herz, Laura M; Johnston, Michael B

2013-05-31

466

CADAT field-effect-transistor simulator  

NASA Technical Reports Server (NTRS)

CADAT field-effect transistor simulator (FETSIM) analyzes dc and transient behavior of metal-oxide-semiconductor (MOS) circuits. Both N-MOS and P-MOS transistor configurations in either bulk of silicon-on-sapphire (SOS) technology and almost any combination of R/C elements are analyzed.

1981-01-01

467

CARBON NANOTUBE TRANSISTORS, SENSORS, AND A Dissertation  

E-print Network

CARBON NANOTUBE TRANSISTORS, SENSORS, AND BEYOND A Dissertation Presented to the Faculty of Philosophy by Xinjian Zhou January 2008 #12;#12;CARBON NANOTUBE TRANSISTORS, SENSORS, AND BEYOND Xinjian Zhou, Ph. D. Cornell University 2008 Carbon nanotubes are tiny hollow cylinders, made from a single

McEuen, Paul L.

468

How to teach a billion transistor  

E-print Network

How to teach a billion transistor chip a new trick Dr. ir. Bart Kienhuis University Leiden, LIACS 500 1000 1500 2000 2500 2000 2001 2002 2003 2004 2005 2006 BillionMAC/s HDTV MPEG4 Video over IP 3G;14 FPGA Programming FPGA is flexible in Hardware and Software... How to teach a billion transistor chip

Kienhuis, Bart

469

/GaAs (001) Metamorphic Buffer Layers  

NASA Astrophysics Data System (ADS)

The design of metamorphic buffer layers for semiconductor devices with reduced defect densities requires control of lattice relaxation and dislocation dynamics. Graded layers are beneficial for the design of these buffers because they reduce the threading dislocation density by (1) allowing the distribution of the misfit dislocations throughout the buffer layer therefore reducing pinning interactions, and (2) enhancing mobility from the high built-in surface strain which helps to sweep out threading arms. In this work, we considered heterostructures involving a linearly-graded (type A) or step-graded (type B) buffer grown on a GaAs (001) substrate. For each structure type, we studied the equilibrium configuration and the kinetically-limited lattice relaxation and non-equilibrium threading dislocations by utilizing a dislocation dynamics model. In this work, we have also considered heterostructures involving a constant composition ZnS y Se1- y device layer grown on top of a GaAs (001) substrate with an intermediate buffer layer of linearly-graded (type C) or step-graded (type D) ZnS y Se1- y . For each structure type, we studied the requirements on the thickness and compositional profile in the buffer layer for the elimination of all mobile threading dislocations from the device layer by the dislocation compensation mechanism.

Kujofsa, T.; Ayers, J. E.

2014-08-01

470

Simulation of electrical properties in ion implanted GaAs  

NASA Astrophysics Data System (ADS)

Computer simulation and analysis of our data compared to published results on the activation of impurity dopants in GaAs, have lead to the establishment of a theoretical model for the electrical properties of GaAs doped by ion implantation and annealed using rapid thermal annealing. A comparison of the behavior of different dopant species have shown that all implants in GaAs have almost the same activation mechanism except for the amphoteric Si implants where electrical activity increased normally with annealing times and temperature up to 900? C, then decreased showing that a compensating mechanisms taking place at temperature higher than 850? C. Finally the Si implanted GaAs become P type for longer annealing times at high temperatures. The purpose of our work was to establish a theoretical model capable of explaining the behavior of Si dopants in GaAs, from relationship between the annealing conditions of Si in GaAs and the electrical properties of Si implanted in GaAs.

Ali-Boucetta, H.; Bensalem, R.; Alleg, S.; Smith, A.; Gwilliam, R.; Sealy, B.

2009-11-01

471

The development of integrated chemical microsensors in GaAs  

SciTech Connect

Monolithic, integrated acoustic wave chemical microsensors are being developed on gallium arsenide (GaAs) substrates. With this approach, arrays of microsensors and the high frequency electronic components needed to operate them reside on a single substrate, increasing the range of detectable analytes, reducing overall system size, minimizing systematic errors, and simplifying assembly and packaging. GaAs is employed because it is both piezoelectric, a property required to produce the acoustic wave devices, and a semiconductor with a mature microelectronics fabrication technology. Many aspects of integrated GaAs chemical sensors have been investigated, including: surface acoustic wave (SAW) sensors; monolithic SAW delay line oscillators; GaAs application specific integrated circuits (ASIC) for sensor operation; a hybrid sensor array utilizing these ASICS; and the fully monolithic, integrated SAW array. Details of the design, fabrication, and performance of these devices are discussed. In addition, the ability to produce heteroepitaxial layers of GaAs and aluminum gallium arsenide (AlGaAs) makes possible micromachined membrane sensors with improved sensitivity compared to conventional SAW sensors. Micromachining techniques for fabricating flexural plate wave (FPW) and thickness shear mode (TSM) microsensors on thin GaAs membranes are presented and GaAs FPW delay line and TSM resonator performance is described.

CASALNUOVO,STEPHEN A.; ASON,GREGORY CHARLES; HELLER,EDWIN J.; HIETALA,VINCENT M.; BACA,ALBERT G.; HIETALA,S.L.

1999-11-01

472

Bipolar II depression in late life: prevalence and clinical features in 525 depressed outpatients  

Microsoft Academic Search

Background: Late-life bipolar II depression has not been well studied. The aim of the present study was to find the prevalence of late-life (50 years or more) bipolar II depression among unipolar and bipolar depressed outpatients, and to compare it with bipolar II depression in younger patients, looking for differences supporting the subtyping of bipolar II depression according to age

Franco Benazzi

2001-01-01

473

The Mood Disorder Questionnaire: A Simple, Patient-Rated Screening Instrument for Bipolar Disorder  

Microsoft Academic Search

Bipolar disorder is frequently encountered in primary care settings, often in the form of poor response to treatment for depression. Although lifetime prevalence of bipolar I disorder is 1%, the prevalence of bipolar spectrum disorders (e.g., bipolar I, bipolar II, and cyclothymia) is much higher, especially among patients with depression. The consequences of misdiagnosis can be devastating. One way to

Robert M. A. Hirschfeld

474

Looking for bipolar spectrum psychopathology: identification and expression in daily life  

Microsoft Academic Search

ObjectivesCurrent clinical and epidemiological research provides support for a continuum of bipolar psychopathology: a bipolar spectrum that ranges from subclinical manifestations to full-blown bipolar disorders. Examining subthreshold bipolar symptoms may identify individuals at risk for clinical disorders, promote early interventions and monitoring, and increase the likelihood of appropriate treatment. The present studies examined the construct validity of bipolar spectrum psychopathology

Molly A. Walsh; Amethyst Royal; Leslie H. Brown; Neus Barrantes-Vidal; Thomas R. Kwapil

475

Filters of BCH-Algebras Based on Bipolar-Valued Fuzzy Sets  

Microsoft Academic Search

The notions of a bipolar fuzzy regularity, a bipolar fuzzy regular subalgebra, a bipolar fuzzy filter, and a bipolar fuzzy closed quasi filter in BCH-algebras are introduced, and several properties are investigated. A characterization of a bipolar fuzzy filter is provided.

Young Bae Jun; Chul Hwan Park

2009-01-01

476

The relationship between borderline personality disorder and bipolar disorder  

PubMed Central

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

Zimmerman, Mark; Morgan, Theresa A.

2013-01-01

477

The role of lamotrigine in the management of bipolar disorder  

PubMed Central

Lamotrigine has emerged with a distinct place in the pharmacological treatment of bipolar disorder, with the potential to treat and prevent bipolar depression, which is the dominant and arguably most disabling and under-treated phase of the illness. This review examines the published clinical trials of lamotrigine in bipolar treatment. While the data supports its tolerability and safety, the strongest evidence for its efficacy lies in the prevention of bipolar depression, with weaker evidence for the treatment of acute bipolar depression, refractory unipolar and bipolar depression, and rapid cycling bipolar disorder. The total number of published well designed trials is small, even the maintenance evidence is derived from two studies. However, this relative inadequacy compares favorably with the alternative treatment options for bipolar depression, which are marked by poor efficacy or risk of polarity switch. The designation of lamotrigine as first-line treatment for bipolar depression prophylaxis should be done in cognizance of this context, and it would seem prudent to await greater evidence of efficacy before designating lamotrigine as first-line treatment for other bipolar indications. Further randomized controlled trials are required to consolidate the available findings and to explore the boundaries of lamotrigine’s efficacy, which may encompass the soft spectral disorders. PMID:19300575

Ng, Felicity; Hallam, Karen; Lucas, Nellie; Berk, Michael

2007-01-01

478

Multicore Processor Cluster Based Sleep Transistor Sizing Considering Delay Profile  

E-print Network

Multicore Processor Cluster Based Sleep Transistor Sizing Considering Delay Profile Huang Huang, Jeffrey Fan* Abstract-- This paper proposed a novel method to size the sleep transistor by considering and the total size of sleep transistors can be dramatically reduced. In theory, the size of sleep transistor can

Fan, Jeffrey

479

Characterization and modeling of the effects of molecular hydrogen on radiation-induced defect generation in bipolar device oxides  

NASA Astrophysics Data System (ADS)

Hydrogen, in its various forms, has an important and sometimes critical impact on the radiation response and long term reliability of semiconductor integrated circuits (ICs). At present, a relatively large density of hydrogen species is present in even the driest and cleanest of all IC fabrication and packaging processes. High levels of molecular hydrogen are found to be trapped inside certain hermetically sealed IC packages after encapsulation. This is shown to severely degrade the performance of ICs fabricated in both Metal-Oxide-Semiconductor (MOS) and bipolar technologies after ionizing radiation exposure. Furthermore, it is also demonstrated that excess molecular hydrogen dramatically changes the radiation response of bipolar ICs when they are exposed at different dose rates. In particular, it changes the transition dose rates and low dose rate enhancement factor in circuits exhibiting Enhanced Low Dose Rate Sensitivity (ELDRS). Characterization and modeling of the effects of molecular hydrogen on the Total Ionizing Dose (TID) and dose rate response of linear bipolar ICs are presented in this work. By deliberately introducing and controlling molecular hydrogen concentration in test bipolar transistors, enhanced radiation-induced degradation in terms of interface trap and oxide-trapped-charge buildup are characterized at different dose rates. Moreover, annealing experiments are performed at different biases and temperatures after irradiations. From the experimental results, physical models are proposed and implemented through computer simulations to describe the effects of molecular hydrogen. The models incorporate molecular hydrogen cracking and electron/hole recombination reactions to describe the impact of molecular hydrogen on TID and dose rate responses of bipolar ICs. The results of this work should stimulate changes in recipes used during IC fabrication and packaging to ensure proper control of hydrogen contamination. They also suggest that hardness assurance test methods used to qualify radiation tolerant electronic parts need to include the measure of hydrogen content in IC packages. Moreover, molecular hydrogen and its effects on bipolar IC dose rate response, particularly on ELDRS, may help to predict the low dose rate response of target ICs and reduce or even eliminate costly procedures of selecting and qualifying parts for use in the space radiation environment.

Chen, Xiao-Jie

480

Characterization of neutron radiation damage in GaAs  

NASA Astrophysics Data System (ADS)

The NJOY and MARLOWE computer codes are used to characterize neutron damage to GaAs. The fidelity of the components that affect the calculated GaAs damage is examined. The initial defect production is found to be a linear function of the damage energy. Recombination of Frenkel pairs and the distribution of vacancies introduce a nonlinearity in the residual defect population with respect to the damage energy. Consideration of the defect recombinations only provides a slight improvement in the agreement between measured and calculated damage in GaAs but does indicate the areas where more work is needed.

Griffin, P. J.; Luera, T. F.; Kelly, J. G.; Lazo, M. S.

1989-12-01

481

GaAs VLSI technology and circuit elements for DSP  

NASA Astrophysics Data System (ADS)

Recent progress in digital GaAs circuit performance and complexity is presented to demonstrate the current capabilities of GaAs components. High density GaAs process technology and circuit design techniques are described and critical issues for achieving favorable complexity speed power and cost tradeoffs are reviewed. Some DSP building blocks are described to provide examples of what types of DSP systems could be implemented with present GaAs technology. DIGITAL GaAs CIRCUIT CAPABILITIES In the past few years the capabilities of digital GaAs circuits have dramatically increased to the VLSI level. Major gains in circuit complexity and power-delay products have been achieved by the use of silicon-like process technologies and simple circuit topologies. The very high speed and low power consumption of digital GaAs VLSI circuits have made GaAs a desirable alternative to high performance silicon in hardware intensive high speed system applications. An example of the performance and integration complexity available with GaAs VLSI circuits is the 64x64 crosspoint switch shown in figure 1. This switch which is the most complex GaAs circuit currently available is designed on a 30 gate GaAs gate array. It operates at 200 MHz and dissipates only 8 watts of power. The reasons for increasing the level of integration of GaAs circuits are similar to the reasons for the continued increase of silicon circuit complexity. The market factors driving GaAs VLSI are system design methodology system cost power and reliability. System designers are hesitant or unwilling to go backwards to previous design techniques and lower levels of integration. A more highly integrated system in a lower performance technology can often approach the performance of a system in a higher performance technology at a lower level of integration. Higher levels of integration also lower the system component count which reduces the system cost size and power consumption while improving the system reliability. For large gate count circuits the power per gate must be minimized to prevent reliability and cooling problems. The technical factors which favor increasing GaAs circuit complexity are primarily related to reducing the speed and power penalties incurred when crossing chip boundaries. Because the internal GaAs chip logic levels are not compatible with standard silicon I/O levels input receivers and output drivers are needed to convert levels. These I/O circuits add significant delay to logic paths consume large amounts of power and use an appreciable portion of the die area. The effects of these I/O penalties can be reduced by increasing the ratio of core logic to I/O on a chip. DSP operations which have a large number of logic stages between the input and the output are ideal candidates to take advantage of the performance of GaAs digital circuits. Figure 2 is a schematic representation of the I/O penalties encountered when converting from ECL levels to GaAs

Mikkelson, James M.

1990-10-01

482

Sealed bipolar multi-cell battery  

SciTech Connect

A low maintenance battery comprises a sealed casing having a cavity receiving a stack of monopolar and bipolar plates interspersed with mats of fiberglass felt immobilizing electrolyte and forming a gas path for diffusion of oxygen to the negative electrode. The casing contains a single, resealable vent. During charging, oxygen generated at the positive plate diffuses through the mat and decomposes at the negative plate. The negative plate has a larger capacity than the positive plate to prevent evolution of hydrogen. Voltage potential is increased or decreased by placing one or more bipolar plates in series relation between alternating positive and negative monopolar plates that are connected in parallel to respective positive and negative battery terminals. The monoplates are connected in parallel to respective postive and negative battery terminals, by way of bus plates. The resealable vent permits operation by way of the oxygen cycle which prevents loss of electrolyte. The vent prevents invasion of oxygen from the ambient to discharge negative plates.

Rowlette, J. J.

1985-09-03

483

Bipolar membranes with fluid distribution passages  

NASA Technical Reports Server (NTRS)

The present invention provides a bipolar membrane and methods for making and using the membrane. The bipolar membrane comprises a cation-selective region, an anion-selective region, an interfacial region between the anion-selective region and the cation-selective region, and means for delivering fluid directly into the interfacial region. The means for delivering fluid includes passages that may comprise a fluid-permeable material, a wicking material, an open passage disposed within the membrane or some combination thereof. The passages may be provided in many shapes, sizes and configurations, but preferably deliver fluid directly to the interfacial region so that the rate of electrodialysis is no longer limited by the diffusion of fluid through the cation- or anion-selective regions to the interfacial region.

Hitchens, G. Duncan (Inventor); Archer, Shivaun (Inventor); Tennakoon, Charles L. (Inventor); Gonzalez-Martin, Anuncia (Inventor); Cisar, Alan J. (Inventor)

1999-01-01

484

Intense bipolar structures from stratified helical dynamos  

NASA Astrophysics Data System (ADS)

We perform direct numerical simulations of the equations of magnetohydrodynamics with external random forcing and in the presence of gravity. The domain is divided into two parts: a lower layer where the forcing is helical and an upper layer where the helicity of the forcing is zero with a smooth transition in between. At early times, a large-scale helical dynamo develops in the bottom layer. At later times the dynamo saturates, but the vertical magnetic field continues to develop and rises to form dynamic bipolar structures at the top, which later disappear and reappear. Some of the structures look similar to ? spots observed in the Sun. This is the first example of magnetic flux concentrations, owing to strong density stratification, from self-consistent dynamo simulations that generate bipolar, super-equipartition strength, magnetic structures whose energy density can exceeds the turbulent kinetic energy by even a factor of 10.

Mitra, Dhrubaditya; Brandenburg, A.; Kleeorin, N.; Rogachevskii, I.

2014-11-01

485

A safe lithium mimetic for bipolar disorder  

PubMed Central

Lithium is the most effective mood stabilizer for the treatment of bipolar disorder, but it is toxic at only twice the therapeutic dosage and has many undesirable side effects. It is likely that a small molecule could be found with lithium-like efficacy but without toxicity through target-based drug discovery; however, lithium’s therapeutic target remains equivocal. Inositol monophosphatase is a possible target but no bioavailable inhibitors exist. Here we report that the antioxidant ebselen inhibits inositol monophosphatase and induces lithium-like effects on mouse behaviour, which are reversed with inositol, consistent with a mechanism involving inhibition of inositol recycling. Ebselen is part of the National Institutes of Health Clinical Collection, a chemical library of bioavailable drugs considered clinically safe but without proven use. Therefore, ebselen represents a lithium mimetic with the potential both to validate inositol monophosphatase inhibition as a treatment for bipolar disorder and to serve as a treatment itself. PMID:23299882

Singh, Nisha; Halliday, Amy C.; Thomas, Justyn M.; Kuznetsova, Olga; Baldwin, Rhiannon; Woon, Esther C. Y.; Aley, Parvinder K.; Antoniadou, Ivi; Sharp, Trevor; Vasudevan, Sridhar R.; Churchill, Grant C.

2012-01-01

486

Bipolar batteries based on Ebonex ® technology  

Microsoft Academic Search

Continuing work by Atraverda on the production of a composite-laminate form of the Ebonex® material, that can be cheaply formulated and manufactured to form substrate plates for bipolar lead–acid batteries, is described. Ebonex® is the registered trade name of a range of titanium suboxide ceramic materials, typically Ti4O7 and Ti5O9, which combine electrical conductivity with high corrosion and oxidation resistance.Details

A. C. Loyns; A. Hill; K. G. Ellis; T. J. Partington; J. M. Hill

2005-01-01

487

Injection moulding of graphite composite bipolar plates  

Microsoft Academic Search

SGL Technologies GmbH has been developing different moulding technologies for graphite composite bipolar plates (BPP) for PEM fuel cells since 1997. Injection moulding of polypropylene (PP) and phenolic (PF) bonded graphite compounds have been identified as most promising and cost-effective production processes.SGL Technologies has invested in injection moulding machines for moulding both thermoplastic and thermoset materials. In addition, materials and

A. Müller; P. Kauranen; A. von Ganski; B. Hell

2006-01-01

488

A submicrometer high-performance bipolar technology  

Microsoft Academic Search

The description of a submicrometer self-aligned bipolar technology developed to minimize the device topography and to provide shallow profiles for high-performance (ECL) emitter-coupled logic applications is presented. The technology features 0.8-?m design rules, planar beakless field oxide, polysilicon-filled deep trench isolation, and the use of rapid thermal annealing (RTA). Conventional ECL circuits with 35-ps gate delays, a novel AC-coupled active-pull-down

T.-C. Chen; K. Y. Toh; J. D. Cressler; J. Warnock; P.-F. Lu; D. D. Tang; G. P. Li; C.-T. Chuang; T. H. Ning

1989-01-01

489

Composite bipolar plate for electrochemical cells  

DOEpatents

A bipolar separator plate for fuel cells consists of a molded mixture of a vinyl ester resin and graphite powder. The plate serves as a current collector and may contain fluid flow fields for the distribution of reactant gases. The material is inexpensive, electrically conductive, lightweight, strong, corrosion resistant, easily mass produced, and relatively impermeable to hydrogen gas. The addition of certain fiber reinforcements and other additives can improve the properties of the composite material without significantly increasing its overall cost.

Wilson, Mahlon S. (Los Alamos, NM); Busick, Deanna N. (Los Alamos, NM)

2001-01-01

490

Surgical management of bipolar clavicular dislocation.  

PubMed

We present case of bipolar dislocation of the right clavicle in a 26 year-old man. He was treated by open reduction plus internal fixation with Kirschner wires at the acromioclavicular joint, and orthopedic reduction of the sternoclavicular joint plus percutaneous osteosynthesis with Kirschner wires. An excellent (functional and cosmetic) result was obtained. A review of the literature is included, and some aspects of the treatment are discussed. PMID:8372658

Arenas, A J; Pampliega, T; Iglesias, J

1993-01-01

491

Treatment of childhood-onset bipolar disorder  

Microsoft Academic Search

Because pediatric bipolar disorder is a serious condition, there is a substantive need for evidence- based treatments for\\u000a children and adolescents suffering from this condition. A fundamental intervention used in this patient population is pharmacotherapy.\\u000a Despite the importance of medication treatment in this patient population, only limited amounts of methodologically stringent\\u000a data exist pertaining to this form of intervention. The

Robert L. Findling

492

Bipolar hip replacement in sickle cell disease  

Microsoft Academic Search

Summary.   A retrospective study is presented of 26 uncemented bipolar hip replacements for avascular necrosis of the femoral head due\\u000a to sickle cell disease which were carried out between 1987 and 1992. All patients were treated according to a protocol. The\\u000a average follow up was 4.6 years (range 2.1 to 7 years). After operation, the average Harris hip score improved

B. K. S. Sanjay; P. G. Moreau

1996-01-01

493

The core of bicapacities and bipolar games  

Microsoft Academic Search

Bicooperative games generalize classical cooperative games in the sense that a player is allowed to play in favor or against some aim, besides non participation. Bicapacities are monotonic bicooperative games, they are useful in decision mak- ing where underlying scales are of bipolar nature, i.e., they distinguish between good\\/satisfactory values and bad\\/unsatisfactory ones. We propose here a more general framework

Lijue Xie; Michel Grabisch

2007-01-01

494

A Bipolar Interpretation of Fuzzy Decision Trees  

Microsoft Academic Search

Decision tree construction is a popular approach in data mining and machine learning, and some variants of decision tree algorithms\\u000a have been proposed to deal with different types of data. In this paper, we present a bipolar interpretation of fuzzy decision\\u000a trees. With the interpretation, various types of decision trees can be represented in a unified form. The edges of

Tuan-fang Fan; Churn-jung Liau; Duen-ren Liu

2008-01-01

495

Bipolar Fuzzy Mathematical Morphology for Spatial Reasoning  

Microsoft Academic Search

Bipolarity is an important feature of spatial information, involved in the expressions of preferences and constraints about\\u000a spatial positioning, or in pairs of “opposite” spatial relations such as left and right. Imprecision should also be taken\\u000a into account, and fuzzy sets is then an appropriate formalism. In this paper, we propose to handle such information based\\u000a on mathematical morphology operators,

Isabelle Bloch

2009-01-01

496

Electrical Coupling Between Cells and Graphene Transistors.  

PubMed

In this work, both experimental data and a model are presented on the coupling between living cells and graphene solution-gated field-effect transistors. Modified HEK 293 cells are successfully cultured on graphene transistor arrays and electrically accessed by the patch clamp method. Transistor recordings are presented, showing the opening and closing of voltage-gated potassium ion channels in the cell membrane. The experimental data is compared with the broadly used standard point-contact model. The ion dynamics in the cell-transistor cleft are analyzed to account for the differences between the model and the experimental data revealing a significant increase in the total ionic strength in the cleft. In order to describe the influence of the ion concentration resulting from the cell activity, the ion-sensitivity of graphene solution-gated field-effect transistors is investigated experimentally and modelled by considering the screening effect of the ions on the surface potential at the graphene/electrolyte interface. Finally, the model of the cell-transistor coupling is extended to include the effect of ion accumulation and ion sensitivity. The experimental data shows a very good agreement with this extended model, emphasizing the importance of considering the ion concentration in the cleft to properly understand the cell-transistor coupling. PMID:25408432

Hess, Lucas H; Becker-Freyseng, Christoph; Wismer, Michael S; Blaschke, Benno M; Lottner, Martin; Rolf, Felix; Seifert, Max; Garrido, Jose A

2014-11-19

497

Characterization of Pediatric Bipolar Disorder with Quantitative HARDI Tractography Metrics Ryan Payne Cabeen1  

E-print Network

1541 Characterization of Pediatric Bipolar Disorder with Quantitative HARDI Tractography Metrics) analysis. Background: Bipolar disorder (BD) is among the most devastating psychiatric disorders, with great Contributions: We computed and compared quantitative diffusion tractography metrics in children with bipolar

Laidlaw, David

498

Limbic hyperactivation during processing of neutral facial expressions in children with bipolar disorder  

E-print Network

, we extend this paradigm to pediatric bipolar disorder (BD), thus demonstrating traction associated with information processing and emotion regulation. For several reasons, bipolar disorder (BDLimbic hyperactivation during processing of neutral facial expressions in children with bipolar

Baker, Chris I.

499

Biomarkers of bipolar disorder: specific or shared with schizophrenia? Frank Bellivier1,2,4,7  

E-print Network

Biomarkers of bipolar disorder: specific or shared with schizophrenia? Frank Bellivier1 fundamentally influenced thinking about bipolar disorder (BP) and schizophrenia (SZ) for over a century (SZ) and bipolar disorder (BD) are frequently occurring conditions that are recognized as leading

Boyer, Edmond

500

RESEARCH ARTICLE Open Access Inhibition/activation in bipolar disorder: validation  

E-print Network

RESEARCH ARTICLE Open Access Inhibition/activation in bipolar disorder: validation reactivity, Bipolar disorder, Factorial analysis, Scale, Clinical trial, Olanzapine * Correspondence/inhibition levels in all bipolar mood episodes, and to determine whether a clinical description in terms

Paris-Sud XI, Université de