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31	Metal-oxide-semiconductor devices based on epitaxial germanium-carbon layers grown directly on silicon substrates by ultra-high-vacuum chemical vapor deposition Kelly, David Quest. January 1900 (has links) (PDF) Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
32	Ultra-wideband tunable circuit design using silicon-germanium heterojunction bipolar transistors Shankar, Subramaniam 20 May 2010 (has links) This thesis explores the critical advantages of using silicon-germanium (SiGe) HBTs for RF front-end design. The first chapter looks at the SiGe BiCMOS technology platform and its important performance metrics. The second chapter discusses ultra-wide tuneability and the critical role that this functionality can have on real world applications. The third chapter presents simulated and measured results of two wideband ring oscillators (8-18 GHz) designed and fabricated in the Jazz 120 BiCMOS platform. A 7-22 GHz wideband VGA in the 8HP platform is also presented further exemplifying the wideband capabilities of SiGe HBTs. Circuit design Sige Ultra-wide tunable Silicon-germanium Heterojunctions Biopolar transistors Germanium compounds Silicon compounds Wireless communication systems
33	Fabrication modeling and reliability of novel architecture and novel materials based MOSFET devices Dey, Sagnik 28 August 2008 (has links) Not available / text Germanium compounds Silicon compounds
34	XAFS study of solid-solid transitions under high pressure / Wang, Fuming M., January 1998 (has links) Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (p. [139]-145).
35	Structure of and phase transformations in bulk amorphous (GaSb)â†1â†-â†x(Geâ†2)â†x Sapelkin, Andrei V. January 1997 (has links) No description available. 539.72
36	The strongly correlated electron systems CeNiâ†2Geâ†2 and Srâ†2RuOâ†4 Diver, Andrew James January 1996 (has links) No description available. 530.41
37	Operating voltage constraints and dynamic range in advanced silicon-germanium HBTs for high-frequency transceivers Grens, Curtis Morrow 04 May 2009 (has links) This work investigates the fundamental device limits related to operational voltage constraints and linearity in state-of-the-art silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) in order to support the design of robust next-generation high-frequency transceivers. This objective requires a broad understanding of how much "usable" voltage exists compared to conventionally defined breakdown voltage specifications, so the role of avalanche-induced current-crowding (or "pinch-in") effects on transistor performance and reliability are carefully studied. Also, the effects of intermodulation distortion are examined at the transistor-level for new and better understanding of the limits and trade-offs associated with achieving enhanced dynamic range and linearity performance on existing and future SiGe HBT technology platforms. Based on these investigations, circuits designed for superior dynamic range performance are presented. Pinch-in Reliability Safe-Operating Area (SOA) Silicon germanium Dynamic range Intermodulation distortion Linearity Breakdown voltage Avalanche multiplication Bipolar transistors Heterojunctions Bipolar transistors Radio Transmitter-receivers Silicon compounds Germanium compounds
38	Hardness assurance testing and radiation hardening by design techniques for silicon-germanium heterojunction bipolar transistors and digital logic circuits Sutton, Akil Khamisi 04 May 2009 (has links) 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. Bit error rate testing Displacement damage Heterojunction bipolar transistor Radiation effects Radiation hardening by design Silicon germanium Single event upset Ionization Heterojunctions Bipolar transistors Logic circuits Radiation hardening Hardness Germanium compounds Silicon compounds Extreme environments
39	Low-cost SiGe circuits for frequency synthesis in millimeter-wave devices Lauterbach, Adam Peter January 2010 (has links) "2009" / Thesis (MSc (Hons))--Macquarie University, Faculty of Science, Dept. of Physics and Engineering, 2010. / Bibliography: p. 163-166. / Introduction -- Design theory and process technology -- 15GHz oscillator implementations -- 24GHz oscillator implementation -- Frequency prescaler implementation -- MMIC fabrication and measurement -- Conclusion. / Advances in Silicon Germanium (SiGe) Bipolar Complementary Metal Oxide Semiconductor (BiCMOS) technology has caused a recent revolution in low-cost Monolithic Microwave Integrated Circuit (MMIC) design. -- This thesis presents the design, fabrication and measurement of four MMICs for frequency synthesis, manufactured in a commercially available IBM 0.18μm SiGe BiCMOS technology with ft = 60GHz. The high speed and low-cost features of SiGe Heterojunction Bipolar Transistors (HBTs) were exploited to successfully develop two single-ended injection-lockable 15GHz Voltage Controlled Oscillators (VCOs) for application in an active Ka-Band antenna beam-forming network, and a 24GHz differential cross-coupled VCO and 1/6 synchronous static frequency prescaler for emerging Ultra Wideband (UWB) automotive Short Range Radar (SRR) applications. -- On-wafer measurement techniques were used to precisely characterise the performance of each circuit and compare against expected simulation results and state-of-the-art performance reported in the literature. -- The original contributions of this thesis include the application of negative resistance theory to single-ended and differential SiGe VCO design at 15-24GHz, consideration of manufacturing process variation on 24GHz VCO and prescaler performance, implementation of a fully static multi-stage synchronous divider topology at 24GHz and the use of differential on-wafer measurement techniques. -- Finally, this thesis has llustrated the excellent practicability of SiGe BiCMOS technology in the engineering of high performance, low-cost MMICs for frequency synthesis in millimeterwave (mm-wave) devices. / Mode of access: World Wide Web. / xxii, 166 p. : ill (some col.) Frequency synthesizers Millimeter wave devices Semiconductors Silicon compounds Germanium compounds Bipolar transistor Metal oxide semiconductors SiGe BiCMOS Voltage Controlled Oscillator (VCO) Millimeter-wave (mm-wave) Short Range Radar (SRR) frequency prescaler
40	Self organized formation of Ge nanocrystals in multilayers Zschintzsch-Dias, Manuel 05 June 2012 (has links) (PDF) The aim of this work is to create a process which allows the tailored growth of Ge nanocrystals for use in photovoltic applications. The multilayer systems used here provide a reliable method to control the Ge nanocrystal size after phase separation. In this thesis, the deposition of GeOx/SiO2 and Ge:SiOx~ 2/SiO2 multilayers via reactive dc magnetron sputtering and the self-ordered Ge nanocrystal formation within the GeOx and Ge:SiOx~ 2 sublayers during subsequent annealing is investigated. Mostly the focus of this work is on the determination of the proper deposition conditions for tuning the composition of the systems investigated. For the GeOx/SiO2 multilayers this involves changing the GeOx composition between elemental Ge (x = 0) and GeO2 (x = 2), whereas for the Ge:SiOx~ 2/SiO2 multilayers this involves changing the stoichiometry of the Ge:SiOx~ 2 sublayers in the vicinity of stochiometric silica (x = 2). The deposition conditions are controlled by the variation of the deposition rate, the deposition temperature and the oxygen partial pressure. A convenient process window has been found which allows the sequential deposition of GeOx/SiO2 or Ge:SiOx ~2/SiO2 without changing the oxygen partial pressure during deposition. For stoichiometry determination Rutherford back-scattering spectrometry has been applied extensively. The phase separation in the spatially confined GeOx and Ge:SiOx ~2 sublayers was investigated by X-ray absorption spectroscopy at the Ge K-edge. The Ge sub-oxides content of the as-deposited multilayers diminishes with increasing annealing temperature, showing complete phase separation at approximately 450° C for both systems (using inert N2 at ambient pressure). With the use of chemical reducing H2 in the annealing atmosphere, the temperature regime where the GeOx phase separation occurs is lowered by approximately 100 °C. At temperatures above 400° C the sublayer composition, and thus the density of the Ge nanocrystals, can be altered by making use of the reduction of GeO2 by H2. The Ge nanocrystal formation after subsequent annealing was investigated with X-ray scattering, Raman spectroscopy and electron microscopy. By these methods the existence of 2 - 5 nm Ge nanocrystals at annealing temperatures of 550 (GeOx) - 700° C (Ge:SiOx ~2) has been confirmed which is within the multilayer stability range. The technique used allows the production of extended multilayer stacks (50 periods ~ 300 nm) with very smooth interfaces (roughness ~ 0.5 nm). Thus it was possible to produce Ge nanocrystal layers with ultra-thin SiO2 separation layers (thickness ~ 1 nm) which offers interesting possibilities for charge transport via direct tunneling. Photovoltaik Strukturaufklärung Raman-Spektroskopie Rutherford Back Scattering XANES Röntgendiffraktometrie Nanokristall Mehrschichtsystem Germanium Siliciumdioxid Silicium Reaktives Sputtern Entmischung Tunneleffekt Durchstrahlungselektronenmikroskop Quantenpunkt Tempern annealing elemental semiconductors germanium germanium compounds nanofabrication nanoparticle nanocrystal quantum dot phase separation Raman spectra semiconductor growth semiconductor thin films silicon compounds silica reactive sputter deposition superlattice multilayer transmission electron microscopy tunnelling x-ray scattering photovoltaics rutherford back scattering XANES ddc:530 rvk:UM 3300 rvk:UQ 2000 Photovoltaik Strukturaufklärung Raman-Spektroskopie Rutherford Back Scattering XANES Röntgendiffraktometrie Nanokristall Mehrschichtsystem Germanium Siliciumdioxid Silicium Reaktives Sputtern Entmischung Tunneleffekt Durchstrahlungselektronenmikroskop Quantenpunkt Tempern

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