Asymmetric island sidewall growth (AISG) is employed to reduce the threading defect density and to modify the surface/interface properties of semipolar GaN templates and InGaN/GaN quantum wells (QWs). We have found that the microstructures and optical properties of the semipolar InGaN/GaN QWs are well correlated with the threading defect density and surface properties of semipolar growth templates. Without AISG, surface undulation, indium fluctuation, and a relatively high indium content within InGaN layers on conventional GaN templates are observed and correlated with high-density threading defects and the formation of specific microfacets with more N dangling bonds on the surface. With AISG, these semipolar InGaN/GaN QWs on modified GaN templates exhibit a uniform indium distribution in the absence of threading defects. The optical properties of InGaN/GaN QWs are significantly improved, and this improvement is attributed to the surface modification of GaN templates, the reduction in threading defect density, and the higher uniformity of indium distribution within InGaN layers.

中文翻译：

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非对称生长（11 2）GaN模板上改进的半极性绿色InGaN / GaN量子阱及其相关性

采用不对称岛侧壁生长（AISG）来降低穿线缺陷密度并修改半极性GaN模板和InGaN / GaN量子阱（QW）的表面/界面特性。我们已经发现，半极性InGaN / GaN QW的微观结构和光学性质与半极性生长模板的穿线缺陷密度和表面性质密切相关。在没有AISG的情况下，观察到常规GaN模板上InGaN层中的表面起伏，铟波动和相对较高的铟含量，并与高密度穿线缺陷以及表面上具有更多N悬空键的特定微面的形成相关。使用AISG，在没有穿线缺陷的情况下，这些经过修饰的GaN模板上的半极性InGaN / GaN QW表现出均匀的铟分布。