Multi-layer stacks of GaN/n-Al0.5GaN self-assembled quantum dots grown by metal-organic chemical vapor deposition

Abstract

The growth of multi-layer stacks of GaN QDs on n-doped Al0.5GaN template by metal organic chemical vapor phase deposition has been investigated. A two-step growth technique consisting of a low temperature method and high temperature method has been employed to deposit the n-Al0.5GaN spacer-layer over GaN QDs. The third-layer GaN quantum dots with 22nm low temperature and 15nm high temperature Al0.5GaN spacer-layer show uniform-size and excellent optical performance. The photo-luminescence suggests that the peak intensity of GaN QDs with two-step grown spacer-layer has been overall enhanced significantly compared to the low temperature grown spacer-layer with the same thickness.