SiC semiconductor-on-insulator (SOI) structures have been fabricated by the direct deposition of crystalline SiC films on SiO2/Si, Si3N4/Si, and poly-Si/SiO2/Si substrates. The Si substrates were all <100> oriented. The SiC deposition utilized single organosilane precursors (silacyclobutane and trimethylsilane) at temperatures of similar to 1200 degrees C, producing growth rates of similar to 1 mu m/min. X-ray diffraction (XRD) shows that all SIC films are <111> oriented with a 2 theta peak at 35.6 degrees with linewidths between 0.21 and 0.24 degrees. The XRD SiC(111) peak has a maximum for SiC/SiO2/Si SOI structures with SiO2 thickness values of 30-70 nm. Fourier transform infrared (FTIR) spectroscopy performed in the transmission mode revealed only the Si-C bond stretching vibration at 800 cm(-1). In reflection mode FTIR, the Si-C bond vibration peak frequency shifts to 785 cm(-1). The SiC-insulator interfaces of SiC/SiO2/Si and SiC/Si3N4/Si structures are very smooth and free of voids. Initial fabrication of static microelectromechanical systems devices has shown that chemical vapor deposition conformal growth of SiC on structured sacrificial layers is successful.