The vapour growth of IV–VI compounds

Abstract

The various techniques for the vapour growth of both bulk crystals and thin films are briefly described with especial reference to those which have been used in the growth of IV–VI compounds (PbTe etc.). The special problems which arise in the vapour growth of solid solutions between pairs of IV–VI compounds - materials of interest and importance in the IR detector and laser fields - are discussed. As a result of experience in growing Pb 1- x Sn x Te epitaxial layers, a novel and effective vertical epitaxial system, incorporating a thermal block to reduce temperature gradients and fluctuations in the substrate(s) and continuous rotation of the substrate holder in a plane perpendicular to the gas flow, has been designed and constructed. This system has proved very succesful in the growth of Pb 1- x Sn x Te by sublimation and would lend itself to the growth of other compounds both by sublimation and by chemical transport.