Crystal growth of B₁₂As₂ on SiC substrate by CVD method

The growth of B12As2 by chemical vapor deposition on 6H-SiC substrates using hydrides B2H6 and AsH3 as the reactants is described. The growth rate increased from 1.5 mum/h at 1100degreesC to a maximum of 5mum/h at 1400degreesC, and decreased at higher temperatures. X-ray diffraction indicates that the deposits were amorphous when the deposition temperature was below 1150degreesC. Strongly c-axis oriented crystalline B12As2, films were obtained at temperatures higher than 1150degreesC. The orientation relationship of the B12As2 on 6H-SiC was (0001)parallel to(0001). The surface morphology of the B12As2, film grown at 1150degreesC consisted of isolated triangular crystallites. A continuous film forms as the arowth temperature is progressively increased up to 1450degreesC.