Enhancement of optical characteristic of InGaN/GaN multiple quantum-well structures by self-growing air voids

InGaN/GaN multiple quantum-well (MQW) structures with a wavelength range of green were successfully grown on a c-plane GaN template with SiO2 stripe patterns along the [11-20] and [1-100] directions as a mask. The surface morphologies of both samples were investigated using scanning electron microscopy and demonstrated anisotropic growth characteristics of GaN. The optical characteristics were investigated using Raman spectra and photoluminescence (PL). The InGaN/GaN MQW structure grown on the GaN template with SiO2 stripes along the [1-100] orientation exhibited less stress and higher PL intensity. Transmission electron microscopy results indicated that portions of MQWs were grown on an inclined semipolar plane, and air voids occurred only when the direction of the mask stripe was along the [1-100] orientation. The enhancement of the optical characteristic was due to the air-void structure and inclined semipolar quantum-well sidewalls.

Automated summary

In this study, InGaN/GaN multiple quantum-well structures were successfully grown on a c-plane GaN template with SiO2 stripe patterns along different directions as masks. The optical characteristics were found to be enhanced by the air-void structure and inclined semipolar quantum-well sidewalls, with the structure grown along the [1-100] orientation exhibiting less stress and higher PL intensity. Research using scanning electron microscopy and transmission electron microscopy provided insights into the anisotropic growth characteristics and formation of air voids.