Nanostructured Layers of c-SiC Grown by Reaction of Si(111) with Acetylene

摘要

We report on a detailed investigation of the interaction of the acetylene molecules with the clean (111) silicon surface. The diffusion of carbon atoms into the substrate as a function of the annealing temperature forms an epitaxial, cubic and stoichiometric silicon carbide thin layer. The carbonization process has been studied by various surface sensitive techniques such as low energy electron diffraction (LEED), Auger and by scanning electron microscopy (SEM). We have found that the acetylene molecule breaks around 450-500 °C and for temperature up to 600-700 C a 3c-SiC alloy is formed on the clean silicon substrate. For higher temperatures, up to 950 °C, the C atoms have tendency to form additional structures in which they occupy graphitic-like sites with formation of substoichiometric Si(l-x)C(x) alloys.