Study of epitaxial growing process of solid solutions of CdTe-HgTe system in isothermal conditions

Conditions of preparation of the homogeneous epitaxial layers of solid solutions Cdsub(x)Hgsub(1-x)Te were studied by 'evaporation-diffusion' method under isothermal conditions. HgTe single crystal crystallized from mercury solution was used as substance source. In all experiments single crystal films CdTe were used as beds. Bulk analysis of grown films was performed by chemical method using spectrophotometry. Kinetics of epitaxial film growing showed correlation between their thickness, composition and excess pressure of free Hg. Increase in Psub(Hg)sup(ex) results in a decrease of film thickness and in the greater CdTe content in the film. Film thickness and composition are mutually dependent. Change of composition of the first phase over the support affects the mechanism of epitaxial growing. Presence of Te in vapour phase is a necessary condition of growing: film growth is more intensive at the higher rho sub(Te2). Increase of Hg pressure sharply reduces the rate of film growth. It is concluded that the pattern of epitaxial growth of Cdsub(x)Hgsub(1-x)Te is defined by vapour phase composition under isothermal conditions. Using the thin single crystal CdTe films as supports under certain conditions one may obtain homogeneous composition of epitaxial layers of the solid solutions CdTe-HgTe