Flexible electronics using III-V materials for nano-electronics with high electron mobility and optoelectronics with direct band gap are attractive for many applications. This thesis describes a complementary metal oxide semiconductor (CMOS) compatible process for transforming traditional III-V materials based electronics into flexible one. The thesis reports releasing 200 nm of Gallium Arsenide (GaAs) from 200 nm GaAs / 300 nm Aluminum Arsenide (AlAs) stack on GaAs substrate using diluted hydrofluoric acid (HF). This process enables releasing a single top layer compared to peeling off all layers with small sizes at the same time. This is done utilizing a network of release holes that contributes to the better transparency (45 % at 724 nm wavelengths) observed. Fabrication of metal oxide semiconductor capacitor (MOSCAPs) on GaAs is followed by releasing it to have devices on flexible 200 nm GaAs. Similarly, flexible GaSb and InP fabrication process is also reported to transform traditional electronics into large-area flexible electronics.

The gas phase etching of thermal silicon dioxide films was investigated with in situ Fourier Transformed Infrared Spectroscopy (FTIR) and ex situ X-ray Photoelectron Spectroscopy (XPS). The initiation process, the bulk etching of the oxide, and the termination mechanism were characterized as a function of reactant concentration, temperature, and pressure. The experiments were carried out in a custom made vessel with a gas panel and a data acquisition and control system (DA&C) capable of lowering flow and pressure disturbances originated by reactant introduction. The FTIR technique used to monitor the reaction in real time allowed distinguishing reactions that initiated in a gas/solid regime from reactions that started in a gas/liquid/solid regime. This study was focused on the gas/solid initiation process in order to expand the general assumption in published works that a condensed layer is previously required to initiate and sustain the reaction. It was found in this investigation that, depending on the experimental parameters, the water layer is not always a requisite for the initiation of the reaction but a consequence of the etching process. The FTIR data also showed the role in the initiation process of gas phase heterogeneous associated species, specifically (HF)H₂O and (HF)₂H₂O. After the initiation period, the experimental conditions determined the amount of water present on the surface of the sample, which in turn determined the local environment of the reaction and by extension the etching species. Reactions developing in a gas/solid regime were found to be slow, with etching rates of less than 1 °A/sec. Contrarily, reactions taking place in a gas/liquid/solid regime reached etching rates of 100 °A/sec, a maximum value determined by transport limitations. The condensed layer was found to be especially sensitive to temperature since a variation of 15 ° C changed the local environment from gas/liquid/solid to gas/solid. Finally, it was corroborated through the XPS analysis that the removal process in the gas phase leaves the silicon surfaces with high fluorine and oxygen concentrations in the form of SiFₓ and SiOH.

The current semiconductor device manufacturing requires more strict control of plasma etching. In this research, plasma etching was investigated through gas phase characterization and interface reactions. Hydrogen and nitrogen were added to Ar plasmas to manipulate the electro-physical properties that were measured by a Langmuir probe system. Hydrogen addition modified the EEDF (electron energy distribution function) by increasing the electrons in high energy range. Adding N2 formed a strong bi-Maxwellian distribution. Gas addition caused the transition between ohmic and stochastic heating. Ar-CH4-H2 and Ar-N2-H2 plasmas were also tested. Hydrogen atom beam was used on porous silicon dioxide based low-k films to remove silanol groups that were generated due to the damage of films during pattern transfer. At H2 atom beam process at 150 C moved close to 60% silanol groups were removed in less than 3 min with an etching rate of 15 A/min. The apparent activation energy was 2.4 kcal/mol. Hydrogen atoms reacted with Si-O-Si and methyl groups. The etching mechanisms of CH4/H2/Ar plasma for InP were analyzed by a beam reactor system. Sputtering yield was measured, threshold energy was approximately 60 eV. Inert ion beam assisted chemical reactions gave higher etching rate. The CH4 concentration had no strong effect on etching rate after 5%. Etching rate was not sensitive to temperature up to 150 C. The adsorption of methyl groups to the surface was proposed as rate limiting step. Chemical reaction effectively reduced the surface roughness.

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Thesis (M.F.A.)--Rochester Institute of Technology, 1993. / Typescript. Includes bibliographical references (leaf 24).

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xi, 99 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 80-83).

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xiv, 93 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 85-88). WVU users: Also available in print for a fee.