Defects in the crystal structure of Cd x Hg1 − x Te layers grown on the Si (310) substrates

Abstract

Microstructure of the CdTe (310) and CdHgTe (310) layers grown by molecular-beam epitaxy on Si substrates has been studied by the methods of transmission electron microscopy and selective etching. It is established that formation of antiphase domains in the CdHgTe/CdTe/ZnTe/Si(310) is determined by the conditions of formation of the ZnTe/Si interface. Monodomain layers can be obtained by providing conditions that enhance zinc adsorption. An increase in the growth temperature and in the pressure of Te2 vapors gives rise to antiphase domains and induces an increase in their density to the extent of the growth of poly-crystals. It is found that stacking faults exist in a CdHgTe/Si(310) heterostructure; these defects are anisotropically distributed in the bulk of grown layers. The stacking faults are predominantly located in one (111) plane, which intersects the (310) surface at an angle of 68°. The stacking faults originate at the ZnTe/Si(310) interface. The causes of origination of stacking faults and of their anisotropic distribution are discussed.