Crystalline dependence of optical and interfacial properties of InGaN/GaN quantum wells on nonpolar a-plane GaN/r-sapphire

✍ Scribed by Sung-Nam Lee; Jihoon Kim; Hyunsoo Kim

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 647 KB
• Volume: 326
• Category: Article
• ISSN: 0022-0248
• DOI: 10.1016/j.jcrysgro.2011.01.043

✦ Synopsis

We investigated the optical and the crystal qualities of InGaN/GaN quantum wells (QWs) grown on nonpolar a-plane (1 1 -2 0) GaN/r-sapphire by introducing the novel 2-step growth method without low temperature GaN or AlN buffer layer. In spite of achievement of macroscopic specular surface structure of a-plane GaN epilayer, the surface defects were developed after growing InGaN/GaN QWs. The surface defect density of InGaN was decreased by enhancing the crystallinity of a-plane GaN template. From high-resolution X-ray o/2y scan, the interfacial qualities of InGaN/GaN QWs would deteriorate with increasing surface defect density. In addition, high PL emission intensity and uniformity of InGaN/GaN QWs were obtained by improving the crystal quality of a-plane GaN/ r-sapphire due to the abrupt interfacial quality and the reduction of the surface defect in InGaN active regions.