Growth of silicon carbide thin films by hot-wire chemical vapor deposition from SiH4/CH4/H2

Silicon carbide (SiC) thin films were prepared by hot-wire chemical vapor deposition from SiH4/CH4/H-2 and their structural properties were investigated by X-ray diffraction Fourier transform infrared absorption and Raman scattering spectroscopies. At 2 Torr, Si-crystallite-embedded amorphous SiC (a-Si1-xCx:H) grew at filament temperatures (T-f) below 1600 degrees C and nanocrystalline cubic SiC (nc-3C-SiC:H) grew above T-f = 1700 degrees C. On the other hand, At 4 Torr, a-Si1-xCx:H grew at T-f = 1400 degrees C and nc-3C-SiC grew above T-f = 1600 degrees C. When the intakes of Si and C atoms into the film per unit time are almost the same and H radicals with a high density are generated, which takes place at high T-f, nc-3C-SiC grows. On the other hand, at low T-f the intake of Si atoms is larger than that of C atoms and, consequently, Si-rich a-Si1-xCx:H or Si-crystallite-embedded a-Si1-xCx:H grow. (C) 2009 Elsevier B.V. All rights reserved.