| 摘要 |
Epitaxial films of AIIIBV compounds on a substrate of cubic crystal structure are formed by the reaction in the vapour phase in the presence of free H2 and/or a hydride of Group III-B or V-B and in the absence of an oxidizing atmosphere, of a volatile compound of Group III-B with either an element or volatile compound of Group V-B and contacting the resulting reaction mixture with selected externally heated, cubic crystal substrate. The volatile compound of Group III-B may be a hydride, halide, alkyl halide, or alkyl, including partially alkylated boranes, whilst the volatile compound of Group V-B may be a halide, hydride or alkyl. (Specific examples given.) The mol. fraction of the element or compound of Group V-B may be 0.05 to 0.50 and that of the compound of Group III-B may be 0.01 to 0.15, but preferably less than the mol. fraction of the Group V-B element. The temperature of the reaction may be 400-1500 DEG C. Either the Group III-B compound or the Group V-B compound or element may be doped to give specific conductivity types. The substrate may be formed of (a) a compound from elements of Groups III-B and V-B, (b) a compound from elements of Groups II and VI, (c) a compound from elements of Groups I and VII or (d) Si, Ge or a metallic conductor. All the binary AIII-BV compounds are specifically referred to, and GaAs, GaP, InP, AlAs, AlSb and InAs are prepared in the examples. Ternary and quarternary compounds, e.g. GaPAs, GalnP and GalnAsP may also be prepared.
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