| 摘要 |
Phosphides and arsenides of boron, aluminium, gallium, or indium are produced by mixing a volatile compound of the Group IIIB element and a volatile compound of phosphorus, or arsenic in the gas phase at 500-1500 DEG C. in the presence of hydrogen. The partial pressure of the phosphorus or arsenic compound is greater than that of the Group IIIB compound and, when BP is being produced, the partial pressure of phosphorus is at least equal to the decomposition pressure of BP. Halides of P or As, e.g. PCl3, PBr3, PI3, PCl5, PBr5, or AsCl3, may be used and compounds of the Group IIIB element may be chlorides, bromides or iodides, of B, Al, Ga, or In, di-, penta-, or deca-borane, trimethyl-boron, aluminium, gallium, and indium, triethyl-boron, aluminium, or gallium, tri-propyl-, -isopropyl-, or tertiary butyl boron, ethyl substituted penta-, or deca-borane, tri-isobutyl aluminium, or methyl gallium dichloride. The partial pressures in the system may be 85-70% H2, 5-15% Group IIIB element compound, 10-20% P, or As compound. Pressures may be subto super-atmospheric, e.g. 0.1m to 1500 mm. Hg. The reactants may be introduced separately or premixed into a quartz, porcelain, or carborundum tube heated by resistances, or by a Ta, W, Ti, or Mo filament on which the product is formed. The product deposited from the vapour phase may be in the form of a coating on a shaped form. Specific reaction conditions are given for each product. Specification 923,860 is referred to.
|
