Passivation of deep electronic states of partial dislocations in GaAs: A theoretical study

Abstract

The structure and electronic properties of reconstructed cores of 90° partial dislocations in GaAs are studied using first-principles methods. We find that a double-period reconstruction is most stable for an As-core whereas a single-period reconstruction is most stable for a Ga-core. We show that As and Ga dimers induce detrimental deep electronic states. These deep levels can be partially removed by introducing passivating dopants that break dimers in the dislocation core.