Surface carbonization of Si(1 1 1) by C 2H 2 and the subsequent SiC(1 1 1) epitaxial growth from SiH 4 and C 2H 2

Abstract

Surface carbonization of Si(1 1 1) using C 2H 2 as the carbon source was performed at 1343 K and 5 Torr in a thermal chemical vapor deposition reactor. The evolution of the carbonization process as a function of the C 2H 2 treatment time was investigated using atomic force microscopy and X-ray photoemission spectroscopy analytical techniques. It was found that at a C 2H 2 partial pressure of 5.0×10 −2 Torr, the initial SiC nucleation proceeds to increase the surface roughness up to 0.2 nm after 5 min carbonization. When the carbonization is performed up to 8 min, the SiC nuclei saturate, reducing the surface roughness back to its original value at a saturation SiC thickness of about 1.4 nm.Subsequent SiC(1 1 1) epitaxial growth on the 8 min-carbonization surface was found to have a smooth surface morphology and void-free interface.