CHARACTERIZATION OF CADMIUM-ZINC TELLURIDE CRYSTALS GROWN BY CONTACTLESS PVT USING SYNCHROTRON WHITE-BEAM TOPOGRAPHY

Crystals of Cd1-xZnxTe grown by PVT using self-seeding 'contactless' t echnique were characterized using synchrotron radiation (reflection, t ransmission, and Laue back-reflection X-ray topography). Crystals of l ow (x = 0.04) and high (up to x approximate to 0.4) ZnTe content were investigated. Twins and defects such as dislocations, precipitates, an d slip bands were identified. Extensive inhomogeneous strains present in some samples were found to be generated by interaction (sticking) w ith the pedestal and by composition gradients in the crystals. Large ( up to about 5 mm) oval strain fields were observed around some Te prec ipitates. Low angle grain boundaries were found only in higher ZnTe co ntent (x greater than or equal to 0.2) samples.