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The perturbance in the silicon vacancy concentration caused by the presence of TiSi2 films was examined using antimony silicon doping superlattices as a vacancy detector. An order of 1.5 relative vacancy supersaturation was observed in deposited titanium thickness 4-312 nm, 800-850-degrees celsius, 15-600 min. Vacancy injection mechanisms during titanium silicidation involve volume contraction and stress compensation.

A study of the native point-defect parameters in Si by the use of marker layers reveals that the reaction between dopant marker atoms and native point defects does not affect the point defect profile. The study is performed on B and Si self interstitials, which are epitaxially grown superlattices. The study also measures the interstitial diffusivity of Si and B superlattices.

The high reactivity of AlGaAs, when subjected to molecular beam epitaxial regrowth during electron cyclotron resonance (ECR) plasma etching, caused the impurities and defects in AlGaAs. Impurities such as C, Si and O were observed at the semiconductor interfaces despite the in situ ECR processing.

The diffusion in films grown by low temperature molecular-beam epitaxy (MBE) is compared to the diffusion in films grown by solid-phase-epitaxy (SPE) during annealing in vacuum by evaluating the delta-function shaped B- and Sb-dopant spikes in thin Si films. The diffusive behavior of dopants grown by the low temperature MBE is qualitatively different from that in the films which have dopants of the SPE. The relationship indicates that vacancy like defects are essential features of the growth by solid phase epitaxy. The experiment reveals that during the SPE growth, there is a significant widening of the dopant profiles.

The feasibility of using low-temperature molecular beam epitaxy (LT-MBE) in the doping of Si thin films was evaluated. Sb and B dopants were incorporated on epitaxially grown substrates at growth temperatures below or equal to 300 degrees centigrade. The atomic dopant concentrations were then obtained by spectrum analyses. Results show that LT-MBE is capable of incorporating Sb and B dopants into silicon substrates with high unity probability and zero segregation.

The implant activation efficiency of silicon (Si) and beryllium (Be) ions in undoped epitaxial layers of indium aluminum arsenate (InAlAs) and indium gallium arsenate (InGaAs) were measured in a study using organometallic vapor phase epitaxy. Compared to InAlAs, InGaAs obtained dopants with higher activation efficiencies. Low activation was observed in low dose Be implants due to lack of sites. Higher sheet carrier densities were obtained via Si in InAlAs and for both Si and Be saturations exist in the carrier density with increasing annealing temperature.

A dryprocess for reconstructing the surface of virgin GaAs substrates is discussed. The process uses an electron cyclotron resonance hydrogen plasma technique to remove native oxides from the GaAs substrates. The purified substrates are thenannealed at 500 degrees centigrade in ultrahigh vacuum to obtain a reconstructed surface suitable for epitaxial growth. The proposed dry process is vey useful for achieving complete removal of oxygen and good structural order at the epilayer/substrate boundary.

Reports on the use of ultraviolet/ozone cleaning to remove carbon and oxygen from GaAs prior to metalorganic molecular beam epitaxy and metalorganic chemical vapor deposition. Current voltage saturation characteristics displayed by metal-semiconductor field-effect transistors using the cleaning method.

Examines the removal of surface contaminants from gallium arsenide (GaAs) substrates. Utilization of electron cyclotron resonance hydrogen plasma to remove native oxides; Chemical etching of GaAs to reduce carbon and silicon residues; Importance of contamination-free GaAs surface for optoelectronic applications.

Describes a method for the removal of AlGaAs native oxides prior to molecular beam epitaxial overgrowth. Removal of the oxides in an electron cyclotron resonance hydrogen plasma; Application of reflection high-energy electron diffraction; Detection of interfacial impurities by secondary ion mass spectrometry.