Controlling the sulphur content of ZnSe1−ySy epitaxial layers grown by metalorganic chemical vapor deposition using diethyl selenide, hydrogen sulphide, and dimethylzinc

Abstract

Epitaxial layers of ZnSe1−ySy on (100) GaAs substrates have been grown by metalorganic chemical vapor deposition. The reactants used are dimethylzinc (DMZn), hydrogen sulphide (H2S) and diethylselenide (DESe). The DESe has been used rather than the more usual selenium precursor, hydrogen selenide (H2Se). Results on the relationship between the sulphur incorporated into the epilayer and the group VI gas phase reactant molar ratio show a more linear relationship than previously found for the atmospheric pressure growth of this material using the hydrides. Despite the higher growth temperature (450 °C) and nonoptimized conditions the epilayers are shown to be comparable with those grown with hydrides and at lower growth temperatures (280 °C). Low-temperature (10 K) photoluminescence gave near-band-edge emission linewidths of 6.8 meV for the ZnSe0.87S0.13 ternary.