Microscopic structure of the 90° and 30° partial dislocations in galliumarsenide

Abstract

We performed a theoretical investigation on the atomic structure of {111} glidepartial dislocations in gallium arsenide. The calculations were carried out using abinitio total energy methods, based on the density functional theory and thepseudopotential model. We addressed the microscopic structure of the 90° partialand the 30° partial dislocations. Our results show that the atomic configurations ofthe dislocation cores are similar to those proposed for the same dislocations innon-polar semiconductors. For the 90° partial, the double-period reconstruction isenergetically more favourable than the single-period reconstruction. In addition,we computed the interaction of intrinsic defects with the dislocation cores.