Deposition of GaAs Epitaxial Layers by Organometallic CVD: Temperature and Orientation Dependence

Epitaxial layers of have been grown in an atmospheric organometallic CVD system, for a wide variety of gas phase reactant partial pressures and over a broad range of temperature (450°–1050°C). The growth rates for (100), , (110), (11l)Ga, and (11l)As substrates are reported as functions of temperature and gas composition. Three distinct temperature dependent regions of growth are identified, corresponding to a mid‐temperature mass transport limited range, a low‐temperature kinetic controlled regime, and a high‐temperature desorption limited region. The growth rate is studied as a function of the growth parameters and substrate orientation, and is related to the decomposition of the two reactants trimethylgallium and arsine. A model for the epitaxial growth of by the organometallic process is proposed, based on these findings.