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Silicon-on-insulator (SOI) structures formed in the top region of silicon wafers by ion implantation of oxygen were characterized by RBS (Rutherford Backscattering Spectrometry), OPM (Optical Microscopy), SEM (Scanning Electron Microscopy), and TEM (Transmission Electron Microscopy). Specimens taken from these wafers were previously subjected to specific thermal treatment and silicon epitaxial growth. The results of this investigation show that homogeneous, stoichiometric buried SiO₂ layers were formed beneath the silicon wafer surfaces after high-dose oxygen ion implantation (2.0 x 10¹⁸ O⁺/cm², 180 keV/O⁺). No buried SiO₂ layers were observed in the low-dose wafers (1.0 x 10¹⁷ O⁺/cm², 180 keV/O⁺). Solid-phase epitaxial regrowth (SPE) is strongly temperature dependent. The transition from amorphous (caused by ion impact) to crystalline through the SPE process is completed in the high-dose-rate wafers (∼33 μA/cm²), but not in the low-dose-rate wafers (∼17 μA/cm²). Polysilicon layers were formed on both sides of the SiO₂ layer in the low-dose-rate wafers. Evidence shows that both post annealing (>1000°C, 2 hours in N₂) and in-situ annealing (wafer substrate heating at 500°C during oxygen ion implantation) lower the imperfection density of the top surface region of silicon wafers. A silicon epitaxial layer with low levels of crystalline imperfections was able to be grown on these annealed wafers. The results also show that in-situ annealing is more effective than post annealing. The major microdefects in SOI structures observed in this investigation are dislocations.

A relatively simple, yet complete analytical model for predicting the performance of illuminated or unilluminated (dark) pn diodes with arbitrary doping profiles is developed and presented in this dissertation. It can be used to calculate the saturation current, minority carrier density, short circuit current, spectral response, and effective low-high (p-p⁺) junction recombination velocities of such diodes. The model is applied to dark or illuminated n⁺-p-p⁺ diodes as a function of the front and back surface recombination velocities and the bulk doping profiles. The analysis includes heavy doping effects. The results predicted by this model are compared with those predicted by numerical simulation programs. Both results agree well with each other and with the experimental data available. The complete analytical expressions produced by the model can be reduced to simpler forms for the transparent and quasi-transparent cases. These forms agree with the special case expressions developed by others. The new model is a substantial contribution leading to improved understanding of such devices.

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