Deep levels including lattice relaxation: first- and second-neighbor effects

The effects of lattice relaxation on the deep levels due to substitutional impurities in semiconductors are investigated using an extension of a previously developed formalism. Both first- and second-neighbor relaxation are included in the formalism. Using this method, deep level chemical trends and their trends with varying amounts of lattice relaxation are explored. For specific impurities, molecular dynamics is used to calculate the lattice relaxation around an impurity, and its effects on the deep levels are computed using a Green's function technique. The results of the application of this theory to several impurities in Si, GaAs, and Gap are presented and compared with experiment and other theories. (C) 2000 Elsevier Science Ltd. All rights reserved.