STUDIES OF GROWTH-MECHANISM AND SULFUR INCORPORATION IN VPE OF GAAS UNDER NEARLY EQUILIBRIUM CONDITIONS

Detailed investigations of growth rate of GaAs VPE-layers and sulfur incorporation during crystal growth have been carried out under nearly equilibrium conditions at low temperatures (680-degrees-C). The present investigation examines the dependence of growth rate and sulfur incorporation on the initial partial pressures (p-degrees) of GaCl and HCl in the deposition zone. The observed deviation from the 1:1 proportion between GaCl before and HCl after the growth reaction will be discussed in a model of chlorine desorption by GaCl3. The sulfur concentration dependence in the grown layer indicates an identic growth mechanism and supports the idea of sulfur incorporation through an activated complex on the GaAs surface.