GROWTH OF SI-DOPED GAAS(110) THIN-FILMS BY MOLECULAR-BEAM EPITAXY - SI SITE OCCUPATION AND THE ROLE OF ARSENIC

We have studied the relationship between the surface morphology, Si do ping behavior, and arsenic incorporation kinetics for GaAs(110) thin f ilms grown on singular substrates by molecular beam epitaxy. To obtain films with good surface morphology, homoepitaxial growth requires low substrate temperatures and high As:Ga flux ratios. Under these condit ions, the Si-doped layers exhibit n-type behavior. Growth at higher te mperatures and lower As:Ga flux ratios produces films with a poorer mo rphology, the n-type layers become increasingly compensated, and p-typ e layers are eventually formed. This growth-related site switching beh avior and corresponding variation in surface morphology can be attribu ted to a low arsenic surface population, a consequence of the small an d temperature-dependent arsenic incorporation coefficient for growth o n GaAs(110). (C) 1998 American Institute of Physics.