Fast preparation of (111)-oriented β-SiC films without carbon formation by laser chemical vapor deposition from hexamethyldisilane without H2

(111)-oriented beta-SiC films were prepared by laser chemical vapor deposition using a diode laser (wavelength: 808nm) from a single liquid precursor of hexamethyldisilane (Si(CH3)(3)-Si(CH3)(3), HMDS) without H-2. The effects of laser power (P-L), total pressure (P-tot) and deposition temperature (T-dep) on the microstructure, carbon formation and deposition rate (R-dep) were investigated. beta-SiC films with carbon formation and graphite films were prepared at P-L >= 170W and P-to >= 1000Pa, respectively. Carbon formation strongly inhibited the film growth. beta-SiC films without carbon formation were obtained at P-tot = 400-800Pa and P-L = 130-170W. The maximum R-dep was about 50m.h(-1) at P-L=170W, P-tot=600Pa and T-dep=1510K. The investigation of growth mechanism shows that the photolytic of laser played an important role during the depositions.