Chemical and thermal etching of Se-Te whisker crystals

Abstract

A new chemical etchant (saturated solution of iodine in methanol) capable of revealing the sites of emergence of dislocations on the prism faces of Se 90-Te 10 whisker crystals grown from the vapour phase is reported. A systematic detailed study of thermal etching of whisker crystals at various temperatures and the period of etching is also reported. The results of thermal etching are compared with those of chemical etching. Various experiments are performed and it has been shown that the thermal pits are not formed at dislocation sites but are probably due to impurities in the crystal.