Ultraviolet light-driven epitaxial growth of gallium arsenide at reduced substrate temperatures

Abstract

We report on the photodeposition of gallium arsenide on gallium arsenide and silicon at low substrate temperatures utilizing ultraviolet radiation. A 1000 W Hg-Xe arc lamp serves as the light source with triethylgallium and arsine serving as the reactants. In this study, single crystal gallium arsenide thin films are obtained at substrate temperatures of approximately 357°. The electrical, chemical and structural properties of the photodeposited films are presented and the mechanisms involved in the deposition process are discussed. It is found that both photolytic and pyrolytic mechanisms are involved in the deposition process for the experimental conditions considered and that the desorption of excess arsenic is important in the low temperature growth of GaAs using photochemical means.