Understanding the plastic relaxation of strained InGaN layers towards substrates for nitride-based red light emitters

The idea of using relaxed InGaN as templates for the growth of InGaN-based devices has emerged in recent years. We investigate the process of plastic strain relaxation to exploit it for the preparation of good quality InGaN/GaN templates. The (0001)-oriented InGaN relaxes by the introduction of (a+c) misfit dislocations. Several peculiar phenomena of this mechanism are observed: unusual dislocation core dissociation, introduction of crystallographic tilt, anisotropic relaxation and formation of the point defect agglomerations as the traces of gliding dislocations. All of the mentioned aspects have to be addressed in order to prepare uniform highly relaxed InGaN/GaN templates.