Cracks and dislocation structures in AlGaN systems

摘要

We have performed a complex study of the dislocation/crack distribution in the misfit-strained AlGaN/GaN systems. Two different samples were analysed without and with top GaN overlayer. The coexistence of the optically visible dominant cracks with the AlGaN-GaN interface-related subdominant crack system is reported. The structure of the subdominant crack network is analysed; strong correlation between subdominant cracks and the interface-related edge dislocations is revealed.