Low-temperature growth and n-type doping of CdTe by the remote-plasma-assisted metalorganic chemical vapor deposition method

Abstract

Heteroepitaxial layers of CdTe were grown on (1 0 0) semi-insulating GaAs substrates at low temperatures (150–250°C) and at a low pressure of 27 Pa using the remote-plasma-assisted metalorganic chemical vapor deposition (RPA-MOCVD) method. Dimethylcadmium and diethyltelluride were used as the source materials. Hydrogen-plasma radicals produced in a remote source were employed to assist the decomposition of organic source and hence low-temperature growth was achieved. The grown epilayers were single crystalline with resistivity in the order of 10 5 Ω cm for the entire growth range and had smooth surfaces. n-type doping of the layers was then studied. Heavily iodine-doped CdTe layers with carrier concentration in the range of 10 16–10 18 cm −3 could be obtained at a substrate temperature of 150°C using n-butyliodine as a dopant source. These various results on growth, surface morphology and doping studies will be presented.