Formation of SiCSOI structures by direct growth on insulating layers

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 d eposition utilized single organosilane precursors (silacyclobutane and trim ethylsilane) 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 linewidt hs between 0.21 and 0.24 degrees. The XRD SiC(111) peak has a maximum for S iC/SiO2/Si SOI structures with SiO2 thickness values of 30-70 nm. Fourier t ransform infrared (FTIR) spectroscopy performed in the transmission mode re vealed 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). Th e SiC-insulator interfaces of SiC/SiO2/Si and SiC/Si3N4/Si structures are v ery smooth and free of voids. Initial fabrication of static microelectromec hanical systems devices has shown that chemical vapor deposition conformal growth of SiC on structured sacrificial layers is successful. (C) 2000 The Electrochemical Society. S0013-4651(99)12-061-5. All rights reserved.