Epitaxial crystallization in Te-HgTe-CdTe system

A study was made on possibility of preparation of Cdsub(x)Hgsub(1-x)Te epitaxial layers of steady in thickness composition during crystallization from cadmium and mercury solutions in tellurium. In approximation of ideal solution theory isotherms of liquidus of Te-HgTe-CdTe system were calculated for 470, 500, 550 and 600 deg C. Calculation results were used for study of crystallization of Cdsub(x)Hgsub(1-x)Te layers. Epitaxial layers of Cdsub(x)Hgsub(1-x)Te solid solutions were prepared by the method of liquid-phase epitaxy. It was established that layers have the region of variable composition near to substrate of not more, than 10 mm thickness at temperatures of crystallization beginning, not exceeding 500 deg C. In the rest part of layer the composition is practically steady. The dependence of composition of Cdsub(x)Hgsub(1-x)Te solid solution (epitaxial layers grown at 500 deg C temperature of crystallization beginning) on composition of liquid phase was established. It was found that in the investigated region of liquid phase compositions the value of cadmium segregation factor equals approximately 8 and doesn't depend practically on solution composition