The growth of CdTe bulk crystals using the multi-tube physical vapour transport system

Abstract

The control of vapour transport is central to the growth of any crystal from the gas phase and, therefore, a novel multi-tube physical vapour transport (MTPVT) system has been developed at the University of Durham which addresses this requirement directly. This paper reports recent work including some preliminary modelling of the transport in the MTPVT system. A capillary tube is used in the MTPVT system as a flow restrictor and the mass transport rate with respect to pressure drop across the capillary calibrated. The mass of CdTe transported from the source charge to growing crystal through the crossmember capillary is investigated over two separate growth runs of the MTPVT system and the results compared with the values predicted by modelling. The CdTe crystals grown using the MTPVT system have been quality tested using defect revealing etching, photoluminescence measurements, and X-ray diffraction analysis.