In this paper we introduce an approach to decrease mismatch-induced stress in a heterostructure by using radiation processing of substrate before growth of epitaxial layers from gas phase. In the framework of the approach the mismatch-induced stresses in the heterostructure one can also find acceleration of recombination and diffusion of radiation defects from the damaged region during growth from gas phase at high temperature. We also consider an analytical approach for analyzing of mass and heat transfer. The approach gives a possibility to take into account simultaneously spatial and temporal variations of parameters of mass transfer. At the same time the approach gives a possibility to take into account nonlinearity of considered processes.