A5073869547- Semiconductor materials and devices
- Advancements in Semiconductor Devices and Circuit Design
- Semiconductor Quantum Structures and Devices
- GaN-based semiconductor devices and materials
- Nanowire Synthesis and Applications
- Silicon Carbide Semiconductor Technologies
- Semiconductor materials and interfaces
- Radio Frequency Integrated Circuit Design
- Ferroelectric and Negative Capacitance Devices
- Silicon and Solar Cell Technologies
- Fusion materials and technologies
- Integrated Circuits and Semiconductor Failure Analysis
- Quantum and electron transport phenomena
- Ga2O3 and related materials
- Nuclear Materials and Properties
- Electronic and Structural Properties of Oxides
- Advanced Memory and Neural Computing
- Thin-Film Transistor Technologies
- Advanced Semiconductor Detectors and Materials
- Nuclear materials and radiation effects
- Microstructure and Mechanical Properties of Steels
- Experimental Learning in Engineering
- Chemical Synthesis and Characterization
- Photonic and Optical Devices
- ZnO doping and properties
Massachusetts Institute of Technology
2016-2025
IBM (United States)
2022-2024
Bridge University
2022
Moscow Institute of Thermal Technology
2008-2022
Peking University
2020-2022
Tsinghua University
2020-2022
King University
2022
University of California, Santa Barbara
2022
Lehigh University
2022
Hitachi (Japan)
2022
The change in refractive index Delta n produced by injection of free carriers InP, GaAs, and InGaAsP is theoretically estimated. Bandfilling (Burstein-Moss effect), bandgap shrinkage, free-carrier absorption (plasma effect) are included. Carrier concentrations 10/sup 16//cm/sup 3/ to 19//cm/sup photon energies 0.8 2.0 eV considered. Predictions for reasonably good agreement with the limited experimental data available. Refractive changes as large -2/ predicted carrier 8//cm/sup suggested...
The Massachusetts Institute of Technology's iLab project has developed a distributed software toolkit and middleware service infrastructure to support Internet-accessible laboratories promote their sharing among schools universities on worldwide scale. starts with the assumption that faculty teaching online labs or academic departments provide those are acting in two roles different goals concerns. architecture focuses fast platform-independent lab development, scalable access for students,...
Trapping is one of the most deleterious effects that limit performance and reliability in GaN HEMTs. In this paper, we present a methodology to study trapping characteristics HEMTs based on current-transient measurements. Its uniqueness it amenable integration with electrical stress experiments long-term studies. We details measurement analysis procedures. With method, have investigated detrapping dynamics particular, examined layer location, energy level, trapping/detrapping time constants...
We have found that there is a critical drain-to-gate voltage beyond which GaN high-electron mobility transistors start to degrade in electrical-stress experiments. The depends on the detailed biasing of device during electrical stress. It higher OFF state and high-power than at V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DS</sub> = 0. In addition, as |V xmlns:xlink="http://www.w3.org/1999/xlink">GS</sub> | increases, decreases. also stress...
Nanoscale ionic programmable resistors for analog deep learning are 1000 times smaller than biological cells, but it is not yet clear how much faster they can be relative to neurons and synapses. Scaling analyses of transport charge-transfer reaction rates point operation in the nonlinear regime, where extreme electric fields present within solid electrolyte its interfaces. In this work, we generated silicon-compatible nanoscale protonic with highly desirable characteristics under fields....
We propose a new quantum-effect electronic device which consists of two one-dimensional electron waveguides which, over certain interaction length, come in close proximity to each other so that coherent quantum mechanical tunneling can take place between them. The degree coupling the is controlled by modulating, through field-effect action gate, height potential energy barrier separates If an wave packet injected into this one waveguides, then probability density function will oscillate back...
We have carried out systematic experiments of the electrical reliability state-of-the-art GaN HEMTs. found that degradation is mostly driven by electric field and there a critical below which negligible observed. Device associated with appearance prominent trapping behavior. Degradation consistent model defect formation in AlGaN barrier as result high field. postulate lattice defects are introduced excessive stress inverse piezoelectric effect. Electron at these reduces extrinsic sheet...
We have investigated the surface morphology of electrically stressed AlGaN/GaN high electron mobility transistors using atomic force microscopy and scanning after removing gate metallization by chemical etching. Changes in were correlated with degradation electrical characteristics. Linear grooves formed along edges GaN cap layer for all devices. Beyond a critical voltage that corresponds to sharp increase leakage current, pits on at edges. The density size stress time correlate drain...
In this paper, a simple and reliable method to estimate the channel temperature of GaN high-electron mobility transistors (HEMTs) is proposed.The technique based on electrical measurements performance-related figures merit (I D max R ON ) with synchronized pulsed I-V setup.As our involves only measurement, no special design in device geometry required, packaged devices can be measured.We apply different structures validate its sensitivity robustness.
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> We report on InAs pseudomorphic high-electron mobility transistors (PHEMTs) an InP substrate with record cutoff frequency characteristics. This result was achieved by paying attention to minimizing resistive and capacitive parasitics improving short-channel effects, which play a key role in high-frequency response. Toward this, the device design features very thin channel is fabricated through...
AlGaN/GaN high-electron mobility transistors stressed under dc bias at various channel temperatures were studied using transmission electron microscopy for evidence of physical damage. Stressed devices consistently developed crack- and pit-shaped defects in the crystal material drain-side edge gate, whereas side-by-side as-processed unstressed did not show these features. Furthermore, amount damage was found to correlate electrical degradation as measured by change <i...
We present 30-nm InAs pseudomorphic HEMTs (PHEMTs) on an InP substrate with record <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">fT</i> characteristics and well-balanced xmlns:xlink="http://www.w3.org/1999/xlink">f</i> <sub xmlns:xlink="http://www.w3.org/1999/xlink">max</sub> values. This result was obtained by improving short-channel effects through widening of the side-recess spacing ( xmlns:xlink="http://www.w3.org/1999/xlink">L</i>...
Physical neural networks made of analog resistive switching processors are promising platforms for computing. State-of-the-art switches rely on either conductive filament formation or phase change. These processes suffer from poor reproducibility high energy consumption, respectively. Herein, we demonstrate the behavior an alternative synapse design that relies a deterministic charge-controlled mechanism, modulated electrochemically in solid-state. The device operates by shuffling smallest...
We have developed a new methodology to investigate the dynamic ON-resistance (R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</sub> ) of high-voltage GaN field-effect transistors. The technique allows study R transients after switching event over an arbitrary length time. Using this technique, we investigated in AlGaN/GaN high-voltage, high electron-mobility transistors time span ten decades under variety conditions. find that right...
GaN electronics constitutes a revolutionary technology with power handling capabilities that amply exceed those of Si and other semiconductors in many applications. RF, microwave, millimeter-wave GaN-based amplifiers are now deployed commercial communications, radar, sensing systems. transistors for electrical management also starting to reach the marketplace. From dawn this technology, inadequate transistor stability reliability have represented stumbling blocks preventing widespread use...