Dislocation core energies of the 0 degrees perfect, 60 degrees perfect, 30 degrees partial, and 90 degrees partial dislocations in CdTe, HgTe, and ZnTe: A molecular statics and elasticity theory analysis

N Hew and D Spagnoli and L Faraone, MATERIALS TODAY COMMUNICATIONS, 26, 101949 (2021).

DOI: 10.1016/j.mtcomm.2020.101949

Although it is well known that dislocations degrade the electrical properties of devices based on II-VI materials, there is a profound lack of knowledge regarding these dislocations. Molecular statics simulations were used to study the 0 degrees perfect, 60 degrees perfect, 30 degrees partial, and 90 degrees partial dislocations in CdTe, HgTe, and ZnTe. The core energies were determined for the different possible core structures of these dislocations using the Stillinger-Weber potential. The results show that the 0 degrees perfect dislocation is energetically more stable on the shuffle planes compared to the glide planes. For the other dislocations studied, the alpha configuration always has lower energy than the beta configuration. The 60 degrees perfect dislocation is energetically more stable on the shuffle planes for the beta configuration, however, the opposite is true for the beta configuration where it is more stable on the glide planes. The difference in energies between the single-periodic and double-periodic reconstruction was also investigated for the 60 degrees perfect, 30 degrees partial, and 90 degrees partial dislocation on the glide planes. The Stillinger-Weber potential was only able to predict correctly the energetics for 30 degrees partial dislocation with the alpha configuration, while the rest are in disagreement with previous ab-initio studies for semiconductor materials.

Return to Publications page