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 μm/h at 1100 °C to a maximum of 5 μm/h at 1400 °C, and decreased at higher temperatures. X-ray diffraction indicates that the deposits were amorphous when the deposition temperature was below 1150 °C. Strongly c-axis oriented crystalline B12As2 films were obtained at temperatures higher than 1150 °C. The orientation relationship of the B12As2 on 6H-SiC was (0001)〈101¯0〉||(0001)〈112¯0〉. The surface morphology of the B12As2 film grown at 1150 °C consisted of isolated triangular crystallites. A continuous film forms as the growth temperature is progressively increased up to 1450 °C.