The Experts below are selected from a list of 13479 Experts worldwide ranked by ideXlab platform
Connie J Changhasnain - One of the best experts on this subject based on the ideXlab platform.
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gaas based nanoneedle light emitting diode and avalanche photodiode monolithically integrated on a silicon substrate
Nano Letters, 2011Co-Authors: L C Chuang, Forrest G Sedgwick, Roger Chen, Wai Son Ko, M Moewe, Kar Wei Ng, Thaitruong D Tran, Connie J ChanghasnainAbstract:Monolithic integration of III−V Compound Semiconductor devices with silicon CMOS integrated circuits has been hindered by large lattice mismatches and incompatible processing due to high III−V epitaxy temperatures. We report the first GaAs-based avalanche photodiodes (APDs) and light emitting diodes, directly grown on silicon at a very low, CMOS-compatible temperature and fabricated using conventional microfabrication techniques. The APDs exhibit an extraordinarily large multiplication factor at low voltage resulting from the unique needle shape and growth mode.
Paul W Leu - One of the best experts on this subject based on the ideXlab platform.
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ultrathin Compound Semiconductor on insulator layers for high performance nanoscale transistors
Nature, 2010Co-Authors: Kuniharu Takei, Rehan Kapadia, Steven Chuang, Hui Fang, Paul W LeuAbstract:Compound Semiconductor materials such as gallium arsenide and indium arsenide have outstanding electronic properties, but are costly to process and cannot, on their own, compete with silicon when it comes to low-cost fabrication. But as the relentless miniaturization of silicon electronics is reaching its limits, an alternative route of enhanced device performance is becoming more attractive: the integration of Compound Semiconductors within silicon. Ali Javey and colleagues now present a promising new concept to integrate ultrathin layers of single-crystal indium arsenide on silicon-based substrates with an epitaxial transfer method, a technique borrowed from large-area optoelectronics. With this technique, involving the use of an elastomeric stamp to lift off indium arsenide nanowires and transfer them to a silicon-based substrate, the authors fabricate thin film transistors with excellent device performance. A potential route to enhancing the performance of electronic devices is to integrate Compound Semiconductors, which have superior electronic properties, within silicon, which is cheap to process. These authors present a promising new concept to integrate ultrathin layers of single-crystal indium arsenide on silicon-based substrates with an epitaxial transfer method borrowed from large-area optoelectronics. With this technique, the authors fabricate thin-film transistors with excellent device performance. Over the past several years, the inherent scaling limitations of silicon (Si) electron devices have fuelled the exploration of alternative Semiconductors, with high carrier mobility, to further enhance device performance1,2,3,4,5,6,7,8. In particular, Compound Semiconductors heterogeneously integrated on Si substrates have been actively studied7,9,10: such devices combine the high mobility of III–V Semiconductors and the well established, low-cost processing of Si technology. This integration, however, presents significant challenges. Conventionally, heteroepitaxial growth of complex multilayers on Si has been explored9,11,12,13—but besides complexity, high defect densities and junction leakage currents present limitations in this approach. Motivated by this challenge, here we use an epitaxial transfer method for the integration of ultrathin layers of single-crystal InAs on Si/SiO2 substrates. As a parallel with silicon-on-insulator (SOI) technology14, we use ‘XOI’ to represent our Compound Semiconductor-on-insulator platform. Through experiments and simulation, the electrical properties of InAs XOI transistors are explored, elucidating the critical role of quantum confinement in the transport properties of ultrathin XOI layers. Importantly, a high-quality InAs/dielectric interface is obtained by the use of a novel thermally grown interfacial InAsO x layer (~1 nm thick). The fabricated field-effect transistors exhibit a peak transconductance of ~1.6 mS µm−1 at a drain–source voltage of 0.5 V, with an on/off current ratio of greater than 10,000.
Tomasz P Jannson - One of the best experts on this subject based on the ideXlab platform.
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single mode optically activated phase modulator on gaas gaalas Compound Semiconductor rib waveguides
Journal of Applied Physics, 1993Co-Authors: Ray T Chen, Robert Shih, Daniel P Robinson, Tomasz P JannsonAbstract:We report on an optically activated phase modulator (OAM) and modulator array on GaAs‐GaAlAs Compound Semiconductor rib waveguides. A rib waveguide device with an optical activation window of 5 μm in diameter was fabricated. Optical activation was produced by using a HeNe 632.8 nm wavelength as the free‐carrier generator and a 1.3 μm laser as the signal carrier. A 33% modulation depth was observed and 10−2 index modulation was experimentally confirmed on an OAM working in the phase modulation regime. OAMs working in both phase‐ and cutoff‐modulation regimes were further determined by considering the variation of the waveguide confinement factor. An 8.2 dB modulation depth was observed on an OAM working at the cutoff regime. Furthermore, the activation source for the free‐carrier generation is in the mW power region, which significantly reduces the size and cost of all optical switching devices.
L Sugiura - One of the best experts on this subject based on the ideXlab platform.
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comparison of degradation caused by dislocation motion in Compound Semiconductor light emitting devices
Applied Physics Letters, 1997Co-Authors: L SugiuraAbstract:Dislocation glide velocities in GaAlAs/GaAs, InGaAsP/InP, and GaN-based light-emitting devices are estimated. These results are consistent with device degradation rates related to dislocation motion. It is clarified that the long lifetime of GaN-based devices with high dislocation density is principally due to extremely small dislocation mobility, partly due to small shear stress for dislocation motion, and due little to the radiation enhancement effect.
M Meyyappan - One of the best experts on this subject based on the ideXlab platform.
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iii vi Compound Semiconductor indium selenide in2se3 nanowires synthesis and characterization
Applied Physics Letters, 2006Co-Authors: Xuhui Sun, Thuc Dinh Nguyen, M MeyyappanAbstract:The authors report the synthesis of one-dimensional indium selenide nanowire, a III-VI group Compound Semiconductor nanostructure with potential applications in data storage, solar cells, and optoelectronics. Nanoscale gold particles were used as catalysts and growth was also demonstrated using indium as self-catalyst. The growth mechanism is confirmed to be vapor-liquid-solid process by in situ heating experiments in which In and Se were found to diffuse back into the gold catalyst bead forming a Au–In–Se alloy that was molten at elevated temperatures. The morphology, composition, and crystal structure of the In2Se3 nanowires (NWs) were analyzed by scanning electron microscopy, energy dispersive x-ray spectroscopy, and high-resolution transmission electron microscopy.