Download or read book Modeling and Testing of Semi insulating Gallium Arsenide Interdigitated Photodetectors written by Ravindranath T. Kollipara and published by . This book was released on 1994 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling and Testing of Semi insulating Gallium Arsenide Interdigitated Photodetectors written by Ravindranath Tagore Kollipara and published by . This book was released on 1991 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: High speed photodetectors are a necessary element in broad band digital and analog optical communication systems. In this thesis easily integrable planar high speed photodetectors made on undoped semi-insulating (SI) GaAs substrates are modeled and tested. The fabrication process of the detectors is fully compatible with GaAs metal-semiconductor field effect transistor (MESFET) processing technology. Interdigitated fingers are used as the contacts to achieve both high sensitivity and large bandwidth. Detectors made with both ohmic and Schottky contacts are fabricated and tested. The equivalent circuit elements of the interdigitated structure are modeled using accurate lumped element circuit models associated with the various discontinuities of the structure. The results of the model agree well with the experimental results as well as with other published results. Numerical simulation of the SI-GaAs metal-semiconductor- metal (MSM) photodetector is performed. The carriers are tracked after an ideal optical pulse is applied and the intrinsic current as a function of time is computed. Then the influence of all the external circuit elements is included and the output current across the load resistor is computed. The simulated response is compared with other published models. The electrical and optical characteristics of the detectors are measured. For ohmic contact detectors, the dark current increases linearly with bias until some critical field is reached beyond which the dark current increases nonlinearly with bias. The time response of the detectors is measured with a 10 ps pulsed laser operating at - 600 nm and also with a pulsed GaAs /AlGaAs semiconductor laser operating at 850 nm. The ohmic and Schottky contact detectors have approximately the same rise time. The fall time of the Schottky contact detector is much smaller than the fall time of ohmic contact detector. The long fall time of the ohmic detector does not depend on the spacing between contacts. This long fall time is due to the large barrier that exists near the ohmic metal/SI-GaAs cathode contact. No such barrier exists for SI-GaAs MSM photodetector. The simulated impulse response of the SI-GaAs MSM photodetector is compared with the measured impulse response.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 1991 with total page 660 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book American Doctoral Dissertations written by and published by . This book was released on 1990 with total page 768 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Non destructive Semi insulating Gallium Arsenide Resistivity Measurement and Its Simulation written by Wan-yu Shih and published by . This book was released on 1989 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Characterization for Semi insulating Gallium Arsenide microform written by Yu Zhang and published by National Library of Canada = Bibliothèque nationale du Canada. This book was released on 1991 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Comparison of Substrate Conditions in Low temperature Gallium Arsenide and Semi insulating Gallium Arsenide During Terahertz Pulse Generation written by Arun Kumar Alla and published by . This book was released on 2011 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of GaAs photoconductive semiconductor switches (PCSS) for generating THz radiation is well known. Both semi-insulating (SI) and Low-temperature (LT) grown Gallium Arsenide (GaAs) have been used. In this research the material parameters that affects the generated pulse shape is studied and compared. Specifically, the role of traps, its density and concentration, carrier rise time, beam width and decay have been analyzed. An industry standard simulation suite was used in the analysis. Study shows that for both LT-GaAs and SI-GaAs there is an increase in total current density with the application of higher bias voltage. Increase in bias increased the drift component through velocity and depletion width increase. Since SI-GaAs have a relatively larger trap concentration at midgap than LT-GaAs and the carrier recombination rate is also higher in SI-GaAs, the linearity the collected charge plot of SI-GaAs is more affected than that of LT-GaAs PCSS. Consequently, charge collection and rise time is faster in LT-GaAs based PCSS as compared to SI-GaAs and will thus transfer more energy to the load that SI based PCSS. The both LT-GaAs PCSS and SI-GaAs PCSS, the role of traps is an important factor that determines the generated pulse shape and width. Specifically effects of recombination rate, beam width and decay and carrier rise time influences the current density and the shape of THz pulse generated. Further, it was observed that LT-GaAs based photoconductive semiconductor switches have superior resistivity (breakdown fields) and charge collection values when compared to SI-GaAs based photoconductive semiconductor switches.

Download or read book Photoreflectance of Semi insulating Gallium arsenide written by Muriel De La Fargue and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of Semi insulating Gallium Arsenide for Nuclear Radiation Detection written by Richard W. Packard and published by . This book was released on 1990 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of the Photoresponse of Semi insulating Gallium Arsenide written by Gerhard Schumm and published by . This book was released on 1985 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: The photoresponse behavior of semi-insulating GaAs is investigated. The photocarrier lifetime is discussed and the influence of surface and contact recombination is taken into account. Photocurrent-voltage characteristics have been measured and a mechanism for the gain in terms of space charge amplification and avalanching is suggested. The influence of deep level traps on the photoresponse of semi-insulating GaAs is investigated. Furthermore, the photocurrent-temperature dependence is studied and a strong increase of photocurrent below 160 K is reported.

Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2002 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication of GaAs Devices written by Albert G. Baca and published by IET. This book was released on 2005-09 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides fundamental and practical information on all aspects of GaAs processing and gives pragmatic advice on cleaning and passivation, wet and dry etching and photolithography. Other topics covered include device performance for HBTs (Heterojunction Bipolar Transistors) and FETs (Field Effect Transistors), how these relate to processing choices, and special processing issues such as wet oxidation, which are especially important in optoelectronic devices. This book is suitable for both new and practising engineers.

Download or read book Photodetectors written by and published by . This book was released on 2000 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 1904 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Zinc Oxide Nanostructures written by Magnus Willander and published by CRC Press. This book was released on 2014-07-22 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: Zinc oxide (ZnO) in its nanostructured form is emerging as a promising material with great potential for the development of many smart electronic devices. This book presents up-to-date information about various synthesis methods to obtain device-quality ZnO nanostructures. It describes both high-temperature (over 100 C) and low-temperature (under

Download or read book SPIE Publications Index written by and published by . This book was released on 1991 with total page 782 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Science Abstracts written by and published by . This book was released on 1995 with total page 1360 pages. Available in PDF, EPUB and Kindle. Book excerpt: