Defects in GaAs

Abstract

A comprehensive review of defects in GaAs with focus on native point defects and dislocations is given. The effects of these defects on devices are also considered. It is pointed out that a unified point defect model cannot at present be drawn from the available information. The importance of including anti-site defects in the point defect models which have hitherto only considered vacancies and interstitials is stressed. Attention is drawn to the need for understanding the dominant equilibrium native defects in GaAs both from fundamental and technological considerations. In this respect new experimental techniques are suggested to understand and control the defect structure. The current understanding of dislocations in GaAs is very much in its infancy compared to that in elemental semiconductors. Both theoretical work and careful experiments are wanting. This is essential since dislocations have been directly implicated in the degradation of GaAs devices.