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Drive Current (drive + current)

Distribution by Scientific Domains
Physics and Astronomy75%

Selected Abstracts

Electric stress effect on DC-RF performance degradation of 0.18-,m MOSFETS

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2006
C. C. Chen
Abstract We have studied the electric stress effect on DC-RF performance degradation of 64 gate fingers 0.18-,m RF MOSFETs. The fresh devices show good transistor's DC to RF characteristics of small sub-threshold swing of 85 mV/dec, large drive current (Id,sat) of 500 ,A/,m, high unity-gain cut-off frequency (ft) of 47 GHz, and low minimum noise figure (NFmin) of 1.3 dB at 10 GHz. The hot carrier stress for 20% Id,sat reduction causes DC gm and ro degradation as well as the lower RF current gain by 2.35 dB, ft reduction to 35.7 GHz, increasing NFmin to 1.7 dB at 10 GHz and poor output impedance matching. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1916,1919, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21813 [source]

Performance of high-power III-nitride light emitting diodes

PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 5 2008
G. Chen
Abstract The performance of III-nitride based high-power light emitting diodes (LEDs) is reviewed. Direct color high-power LEDs with 1 × 1 mm2 chip size in commercial LUXEON® Rebel packages are shown to exhibit external quantum efficiencies at a drive current of 350 mA ranging from ,60% at a peak wavelength of ,420 nm to ,27% at ,525 nm. The short wavelength blue LED emits ,615 mW at 350 mA and >2 W at 1.5 A. The green LED emits ,110 lm at 350 mA and ,270 lm at 1.5 A. Phosphor-conversion white LEDs (1 × 1 mm2 chip size) are demonstrated that emit ,126 lm of white light when driven at 350 mA and 381 lm when driven at 1.5 A (Correlated Color Temperature, CCT , 4700 K). In a similar LED that employs a double heterostructure (DH) insign instead of a multi-quantum well (MQW) active region, the luminous flux increases to 435 lm (CCT , 5000 K) at 1.5 A drive current. Also discussed are experimental techniques that enable the separation of internal quantum efficiency and extraction efficiency. One technique derives the internal quantum efficiency from temperature and excitation-dependent photoluminescence measurements. A second technique relies on variable-temperature electroluminescence measurements and enables the estimation of the extraction efficiency. Both techniques are shown to yield consistent results and indicate that the internal quantum efficiency of short wavelength blue (, , 420 nm) high-power LEDs is as high as 71% even at a drive current of 350 mA. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

High drive current and high frequency response of GaN nanowire metal-oxide-semiconductor field-effect transistor

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7-8 2010
Jeng-Wei Yu
Abstract We report the techniques of lateral epitaxial growth of horizontally aligned [110] GaN NWs and the photo-enhanced chemical (PEC) oxidation process to enable the registration of crystalline gallium oxide (Ga2O3)/GaN NWs onto their growth sites over the SiO2/p-Si substrates. This method allows the implementation of top-gate Ga2O3/GaN NW-metal oxide semiconductor field effect transistor (MOSFET) using the conventional optical lithography and the metal lift-off procedures. This scheme enables photolithographic fabrication of top-gate Ga2O3/GaN NW-MOSFET of 60 nm dia. and 2 ,m gate length. Device parameters with gm of 40 ,S, saturation current of 90 ,A, and cut-off frequency fT at 22 GHz have been extracted (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

InGaAs channel MOSFET with self-aligned source/drain MBE regrowth technology

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2009
Uttam Singisetti
Abstract InGaAs is a promising alternative channel material to Si for sub-22 nm node technology because of its low electron effective mass (m*) hence high electron velocities. We report a gate-first MOSFET process with self-aligned source/drain formation using non-selective MBE re-growth, suitable for realizing high performance scaled III-V MOSFETs. A W/Cr/SiO2 gate stack was defined on thin (4 nm/2.5 nm) InGaAs/InP channel by an alternating selective dry etch technique. A 5 nm Al2O3 layer was used as gate dielectric. An InAlAs bottom barrier provided vertical confinement of the channel. An in-situ H cleaning of the wafer leaves an epi-ready surface suitable for MBE or MOCVD regrowth. Source/Drain region were defined by non-selective MBE regrowth and in situ molybdenum contacts. First generation of devices fabricated using this process showed extremely low drive current of 2 ,A/,m. The drive current was limited by an extremely high source resistance. A regrowth gap between source/drain and gate was the cause for high source resistance. The gap in the regrowth was because of low growth temperature (400 °C). A modified high temperature growth technique resolved the problem. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]