Reconstructions of the Si-terminated (100) surface in beta-SiC: A theoretical study

Using a self-consistent-charge density-functional based tight-binding appro ach the structural properties and relative stabilities of Si-terminated rec onstructions of the (100) surface in beta-SiC are discussed. All low-energy surfaces are found to be semiconducting. Over a wide range of growth condi tions a model with 2 x 3 periodicity has a low formation energy. Only in a Si-rich environment does a 3 x 2 structure become stable. [S0163-1829(99)04 824-9].