The effect of GaAs surface stabilization on the properties of ZnSe grown by organometallic vapor phase epitaxy

Abstract

Organometallic vapor phase epitaxial growth of ZnSe on GaAs was carried out using dimethylzinc (DMZn) and dimethylselenide (DMSe) as the reactants. Unlike III–V systems, where growth is always started by first introducing columm V precursor, the growth of ZnSe can be initiated either by introducing DMZn first (Zn-stabilization) or DMSe first (Se-stabilization). A systematic study of the properties of ZnSe epilayers, grown under these two surface stabilization conditions, was carried out using photoluminescence (PL) and double crystal X-ray diffraction (DCD). Layers grown on Se-stabilized substrates exhibited superior photoluminescence spectrum, but had higher X-ray full width at half maximum (FWHM) compared to those grown on Zn-stabilized surfaces. Detailed studies revealed that layers grown on Se-stabilized surfaces were titled with respect to the substrate. A possible cause for the differences in the ZnSe layers grown on these two surfaces is proposed.