Growth of Polycrystalline CdS Films by Low-Pressure Metalorganic Chemical Vapor Deposition

Abstract

Polycrystalline CdS films were grown at temperatures between 50 and 400°C by reacting DMCd and H 2 S, and the electrical and optical properties of the films were examined. It was found that the films show a preferential orientation to (0001) direction and that their electrical properties are remarkably influenced by the sulphur vacancy. The resistivity of undoped films ranged from 10 3 to 10 7 Ω·cm and became maximum at about 250–300°C. Furthermore, the resistivity of the films could be successfully reduced to about 10 -1 Ω·cm by doping Al as a donor impurity.