Nitrogen doping of polycrystalline 3C-SiC films grown using 1,3-disilabutane in a conventional LPCVD reactor

The chemical, structural, and electrical characteristics of in situ doped SiC films grown from 1,3-disilabutane and NH3 at various growth temperatures, 650-850degreesC, are investigated by means of X-ray photoelectron spectroscopy, X-ray diffractometry, and four-point probe. The nitrogen is successfully incorporated throughout the SiC film. The doped films exhibit lower resistivities than the undoped films deposited at the same temperature, except for the films deposited at 650degreesC. As the deposition temperature increases, the electrical resistivity is shown to increase and then decrease,, peaking at 750degreesC. The resistivity of the polycrystalline SiC films is further controlled by adjusting the NH3 flow rate in the reactor. The lowest resistivity of 0.02 Omega cm is achieved for the film deposited at 800degreesC and the NH3 flow rate of 5 sccm. The post-deposition annealing is shown to further lower the film resistivity. (C) 2003 Elsevier B.V. All rights reserved.