STRUCTURAL AND ELECTRICAL NONUNIFORMITIES IN THIN CDTE LAYERS GROWN ON INSB BY MBE

Electrical measurements made on CdTe layers grown on (001) InSb substrates reveal significant non-uniformities as a function of depth. As there is a small mismatch between the lattice constants for CdTe and InSb, extended defects resulting from strain relief in the epilayer are believed to have an important influence on the electrical properties and, with the aid of computer modelling to simulate x-ray diffraction rocking curves, the distribution of structural defects is being explored. Examples are presented of carrier concentration depth profiles in the vicinity of the CdTe-InSb interface for samples grown under a variety of different conditions and the relationship between the observed electrical non-uniformity and the distribution of dislocations resulting from strain relief is discussed.