1319560 Epitaxial III-V film NORTH AMERICAN ROCKWELL CORP 4 June 1970 7566/73 Divided out of 1139311 Heading C1A An epitaxial film of a Group III-V compound on a monocrystalline sapphire (α-Al 2 O 3 ) substrate whose surface orientation is (0001), (1123), (0112), 1125), or (1126), or is about 10‹ from the (0112) plane, may be produced by introducing one or more gaseous Group V hydrides or alkyls and one or more gaseous Group III alkyls into a reactor containing the heated substrate. The orientation of the film may be (111) or (110). Binary and mixed compounds are exemplified. The reactants may be Me 3 Ga, Et 3 Ga, Me 3 Al, Et 3 Al, Me 3 In, Et 3 In, Ph 3 , Me 3 P, AsH 3 , Me 3 As, SbH 3 , Me 3 Sb, and may be introduced under reduced pressure in a carrier gas, e.g. H 2 , He, Ar, N 2 , with the Group V compound in excess. Small amounts of e.g. AsCl 3 and/or HCl may be present. The substrate may be placed on a SiC-coated C pedestal heated by RF induction to 650-800‹ C. The film may be doped during formation by introducing e.g. H 2 Se or H 2 S (n-type), Me 2 Zn, Et 2 Zn or Me 2 Cd (p-type). Multilayers of different Group III-V compounds may be formed.