The core structure of extended dislocation in Cd0.9Zn0.1Te was observed by high resolution transmission electron microscopy (HRTEM). The dissociate mechanism of basal dislocation in Cd0.9Zn0.1Te was studied by using Digital Micrograph (DM) software. Furthermore, stacking fault energy of Cd0.9Zn0.1Te single crystal was calculated to be 9.17 mJ/m(2) which is lower compared with the semiconductors with diamond structures, such as Si and Ge. The reason of low stacking fault energy of Cd0.9Zn0.1Te was investigated to be the increase of the fractional ionicity of the bonding by using Phillips theory. (C) 2012 Elsevier B.V. All rights reserved.