LOW-PRESSURE CHEMICAL-VAPOR-DEPOSITION OF SILICON-CARBIDE THIN-FILMS FROM HEXAMETHYLDISILANE

Silicon carbide thin films were grown by low pressure chemical vapor d eposition using hexamethyldisilane Me3SiSiMe3 as the single-source pre cursor. Deposition of uniform thin films on Si(1 1 1) substrates was c arried out at temperatures 1123-1323 K in a hot-wall reactor. The grow th rates were 0.9-55 nm min-1 depending on the conditions employed. Es timated energy of activation is 110 kJ mol-1. Bulk elemental compositi on of the thin films, studied by an electron probe X-ray microanalyzer , is best described as SiC(x) (x = 0.8-2.3). The Si/C ratio increased with increasing temperature of deposition. The films were cubic polycr ystals, a = 0.435-0.438 nm, as indicated by scanning transmission elec tron microscopy, electron diffraction and X-ray diffraction. The latti ce parameter decreased with increasing temperature of deposition. Elem ental distribution within the films, studied by Auger depth profiling and X-ray photoelectron spectroscopy, was uniform. Gas phase products H-2, CH4, C2H4, Me3SiH and Me4Si were identified and possible reaction pathways were proposed.