Method of manufacturing a p-type compound semiconductor thin film containing a III-group element and a v-group element by metal organics chemical vapor deposition

摘要

A p-type GaAs or AlGaAs thin film is formed by a MOCVD method. In the growing step of the thin film, the thin film is doped with a high concentration of carbon atoms forming an acceptor level such that the carrier concentration of the thin film falls within the range of between 1×10.sup.18 cm.sup.-3 and 1×10.sup.20 cm.sup.-3. At least one of trimethyl gallium and trimethyl aluminum is used as a raw material gaseous compound of III-group element, and arsine is used as a raw material gaseous compound of V-group element. The thin film is formed by an epitaxial growth under the molar ratio V/III of the V-group element supply rate to the III-group element supply rate, which is set at such a small value as 0.3 to 2.5, the temperature of 450 to 700° and the pressure of 1 to 400 Torr. The thin film formed under these conditions exhibits a mirror-like smooth surface, and the film-growth rate is dependent on the supply rate of the V-group element.