Theoretical investigation on fundamental properties of glide partial in CdTe based on lattice theory of dislocation

Abstract

The core structure and Peierls stress of 30° partial dislocation are researched on the basis of lattice theory of dislocation to further recognize the mechanical properties of CdTe. The surface effect and elastic strain energy missed in classical PN model have been considered in calculations. In addition, the influences of γ- surface fitting on estimation of core width and Peierls stress are analysed. Research results indicate that the rectification of surface effect to dislocation fundamental properties is more evident for narrower dislocations. Since the intrinsic stacking-fault energy(SFE) of CdTe is far lower than the unstable SFE, the difference between the results calculated by using original and effective γ- surface is negligible. More extensive, for crystal whose SFE satisfies the condition mentioned, the original γ- surface can be used for investigation of dislocation properties directly. The deviation of fitted γ- surface from the numerical result will result in non-negligible influence on the estimated result of Peierls stress, and affect the analysis of metastable state. The core width and Peierls stress are about 0.64∼0.73b and 1∼2GPa, respectively. The research results are useful for better understanding and utilization of semiconductor CdTe.