Investigation of the V-pit related morphological and optical properties of InGaN∕GaN multiple quantum wells

In this work, the effects of large V-pits on the morphological and optical properties of InGaN∕GaN multiple quantum wells (MQWs) were studied using scanning electron microscopy, transmission electron microscopy, and photoluminescence. InGaN∕GaN MQWs with high-density large V-pits were grown by metal organic chemical vapor deposition. In addition to the regular c-plane MQWs, the MQWs grown on the {101¯1} faceted sidewalls of the V-pits were also observed, which gave much higher emission energies than those of the c-plane MQWs. Furthermore, when the low-temperature GaN buffer was very thin, the {112¯m} (m⩾2) faceted sidewalls of the V-pits were observed. It was then found that MQWs grown on such sidewalls had emission energies between those of the c-plane MQWs and those of the {101¯1} faceted sidewall MQWs.