Existing data which described the dependence of the concentrations of defects (SAs, ZnGa, SiGa, SbGa, EL2) in GaAs grown by organometallic vapor phase epitaxy, upon the partial pressures of arsine, PAs, and dopant-containing gases in the input gas stream, were analyzed by using a simple model. It was found that As4 was the predominant species of As in the vapor in equilibrium with solid at the growth interface. The electron concentration which governed the charge state of the defect being formed was proportional to PAs3/4. Regardless of the dopant concentration, the Fermi level during defect formation lay above the ionization levels of deep donors but below that of shallow donors. The atomic structure of the mid-gap electron trap, EL2, was stoichiometrically equivalent to the As antisite, AsGa.

Defect Formation in GaAs Grown by Organometallic Vapor Phase Epitaxy and the Structure of the Native Defect EL2. R.A.Morrow: Journal of Crystal Growth, 2002, 241[1-2], 57-62