Plastic Deformation of CdTe Single Crystals II. Photoplastic Effect of II-VI Compounds

In-situ observations by TEM reveal that dislocation velocity is not influenced by light illumination, indicating that the cause of the photoplastic effect (PPE) in II-VI compounds is not a change in the dislocation mobility. Densities of dislocations and loops left after plastic deformation in light are about an order of magnitude higher than those in darkness. These results together with the results of mechanical tests and those given in Part I (J. Phys. Soc. Jpn. 49 (1980) 1909) lead to a conclusion that the PPE is caused by the decrease in mean free path of multiplied dislocations. Jog formation by cross slip resulting in immobilization of glide dislocations is considered to be enhanced by their interaction with charged point defects that trap minority carriers generated by illumination.