EPITAXIAL INTERFACES BETWEEN SEMICONDUCTORS

Consideration is given to the principal physical regularities of epitaxial interfaces formation and blurring into transition regions between a crystal substrate and an epitaxial film grown on the substrate. Epitaxial interfaces are described on the basis of dislocation model of low angle intergrain boundaries with allowing for misfit and incoherence in the bond of conjugating crystal lattices of semiconductors. The temperature and concentration dependences of lattice parameters are taken into account. Experimental data on transition regions in epitaxial structures are discussed on the basis of model concepts on the mechanisms operating in substrate treatment, in film growth, and in the surroundings. The quantitative criteria are given for a transition layer width near the epitaxial film-substrate and film film interfaces. It has been shown that local values of properties over the film thickness should be found for eliminating the influence of size effects on the transition layer width. The results of mathematical simulation of epitaxial interfaces formation by the probability statistical methods and by the solution of kinetic equations of atomic motion are discussed. Consideration is also given to the ways of improving structural and electrophysical properties of the interface in epitaxial multilayer devices. © 1979.