6533b821fe1ef96bd127b692

RESEARCH PRODUCT

Vapor phase epitaxy of Hg1−xCdxI2 layers on CdTe substrates

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Vapor phase epitaxy (VPE) has been studied to grow Hg1 − xCdxI2 epitaxial layers on CdTe bulk substrates. The effect of the VPE growth conditions on the morphology, composition and crystalline quality of Hg1 − xCdxI2CdTe heterostructures has been investigated. It has been shown that 10–30 μm thick Hg1 − xCdxI2 layers can be successfully grown using an α-HgI2 polycrystalline source under isothermal conditions at a temperature in the range 170–240°C for the time period 20–50 h. Interestingly, the VPE growth was found to consist of two successiv stages with different kinetics as follows: (1) a fast growth of an HgI2 platelet layer on the CdTe substrate surface and (2) a slow growth of an Hg1 − xCdxI2 layer on the surface of the platelet layer. The Hg1 − xCdxI2 layers exhibited single-crystalline structure when the layer composition has been varied in the wide range x = 0.24−0.67. The particular role of the HgI2 platelet layer morphology in controlling the composition uniformity throughout the thickness of the Hg1 − xCdxI2 layer has been demonstrated.