Optimal GaAs(100) substrate terminations for heteroepitaxy

The quality of heteroepitaxial growth of II-VI materials on III-V substrates, such as ZnSe on GaAs(100), depends strongly on the atomic structure and stoichiometry of the substrate. We define and describe those structures that optimize heteroepitaxial interface growth on GaAs(100) and related surfaces, and propose specific models for the c(6×4), ‘‘3×1’’, (4×6), an As-lean version of the (2×4), and Se substitutional such as the (4×3). It is proposed that a good heteroepitaxial interface, with no extraneous fields and no charge imbalance, is achieved with substrate structures which lead directly to the appropriate interface stoichiometry.