Ab initio calculation of the structural and electronic properties of the SiC (100) Surfaces

In this work, we have calculated ab initio the structural and electronic properties of both the C- and Si-terminated SiC (100) surfaces in the c(2×2) and (2×1) reconstruction patterns, respectively. Based on our results, we found that the Si-terminated surfaces is dominated by weak bonded Si-dimers, which is stabilized only at Si-rich conditions, leading to a (3×2) or more complex reconstruction patterns, as verified experimentally. Also, our results show that the C-terminated surfaces is characterized by strong triply-bonded C-dimers, in a c(2×2) reconstruction pattern, which consists of C2 pairs over Si bridge sites, which is consistent with the experimental results.