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Development of Indium Arsenide Quantum Well Electronic CircuitsBergman, Joshua 09 July 2004 (has links)
This dissertation focuses on the development of integrated circuits that employ InAs quantum well electronic devices. There are two InAs quantum well electronic devices studied in this work, the first being the pseudomorphic InAs/In₀.₅₃Ga₀.₄₇As/AlAs resonant tunneling diode (RTD) grown on an InP substrate, and the second being the InAs/AlSb HEMT. Because of there is no semi-insulating substrate near the InAs lattice constant of 6.06 Å this work develops monolithic and hybrid integration methods to realize integrated circuits. For the case of hybrid RTD circuits, a thin-film integration method was developed to integrate InAs/In₀.₅₃Ga₀.₄₇As/AlAs RTDs to prefabricated CMOS circuits, and this technique was employed to demonstrate a novel RTD-CMOS comparator. To achieve higher speed circuit operation, a next-generation RTD fabrication process was developed to minimize the parasitic capacitance associated with the thin-film hybridization process. This improved fabrication process is detailed and yield and uniformity analysis is included. Similar InP-based tunnel diodes can be integrated with InP-based HEMTs in monolithic RTD-HEMT integrated circuits, and in this work elementary microwave circuit components were characterized that co-integrate InP-based tunnel diodes with HEMTs. In the case of the InAs/AlSb HEMT, the monolithic approach grows the HEMT on a metamorphic buffer on a GaAs substrate. The semiconductor material and process development of the InAs/AlSb HEMT MMIC technology is described. The remarkable microwave and RF noise properties of the InAs/AlSb HEMT were characterized and analyzed, with special attention given to the strong effects of impact ionization in the narrow bandgap InAs channel. Results showed the extent to which impact ionization affects the small-signal gain and noise figure of the HEMT, and that these effects become less prevalent as the frequency of operation increases.
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