Theoretical investigation of the equilibrium surface structure of si1-x-ygexcy alloys
Journal
Surface Science
Date Issued
December 5, 1998
Author(s)
DOI
10.1016/S0039-6028(98)00758-4
Abstract
We investigate the surface structure of SiGeC alloys at typical growth temperatures using Monte Carlo simulations within the empirical potential formalism. We find a strong tendency of carbon to segregate to the top layer. As a consequence, germanium segregation is drastically reduced. The carbon composition profile oscillates in the subsurface layers, with a marked enhancement in the third layer. Si-C dimers are the favored surface bonding geometry, and are mostly found in (2 × 2) and c(4 × 2) arrangements.