Investigation of InGaN/GaN multiple quantum wells with strain relief behavior for light-emitting diodes

In this paper, we studied a method to reduce the compressive strain in the InGaN/GaN multiple quantum well (MQW) structures by inserting a strain relief layer between n-GaN and MQWs. The improvements in the interface quality and the optical properties were investigated by photoluminescence (PL) and high-resolution X-ray diffraction (HRXRD) analysis. The samples showed S-shaped emission energy peak and stronger band filling effect in the band tail model. It exhibited the higher activation energy and reduced localization effect. In addition, we have characterized the interface quality and optical properties by strain relief in InGaN/GaN multiple quantum wells based on the temperature-dependent PL analysis. The experimental results would be discussed with supporting models.