Criteria For (111) Oriented Heteroepitaxial Growth Of Zinc Blende Crystals On (10U) Oriented Substrates

In order to account for (100) and/or (111) oriented heteroepitaxial growth of CdTe on (100)GaAs, we have proposed a theoretical model based on the formation, during the early stage of the growth, of stable clusters of chemically bound tellurium atoms. In this model we consider not only geometrical features, but also the constraints for symmetries, bond - angles and bond-lengths associated with the growth of CdTe along the requested orientation. In analysing the applicability and the use of this model in more general cases, we are able to express, through lattice mismatch, relatively precise criteria for explaining and predicting possible regularities in the heteroepitaxial growth features on (100) surfaces of zinc blende crystal structures. As an example, it is explained why ZnTe, which is very similar to CdTe, is always (100) oriented on (100) GaAs and never (111). It is also shown why for ternary compounds the (111) oriented growth is obtained only for compositions x < 0,17 in the case of ZnxCdi-xTe on GaAs and x < 0,53 for MnxCdi-xTe-GaAs.