Chery N, Ngo T H, Chauvat M P, Damilano B, Courville A, DE Mierry P, Grieb T, Mehrtens T, Krause F F, Müller-Caspary K, Schowalter M, Gil B, Rosenauer A, Ruterana P
CIMAP, 6 Boulevard du Maréchal Juin, Caen, France.
Laboratoire Charles Coulomb, Batiment 21, Campus Triolet, Université de Montpellier, Montpellier, France.
J Microsc. 2017 Dec;268(3):305-312. doi: 10.1111/jmi.12657. Epub 2017 Oct 11.
In this work, we analyse the microstructure and local chemical composition of green-emitting In Ga N/GaN quantum well (QW) heterostructures in correlation with their emission properties. Two samples of high structural quality grown by metalorganic vapour phase epitaxy (MOVPE) with a nominal composition of x = 0.15 and 0.18 indium are discussed. The local indium composition is quantitatively evaluated by comparing scanning transmission electron microscopy (STEM) images to simulations and the local indium concentration is extracted from intensity measurements. The calculations point out that the measured indium fluctuations may be correlated to the large width and intensity decrease of the PL emission peak.
在这项工作中，我们分析了发射绿光的InGaN/GaN量子阱（QW）异质结构的微观结构和局部化学成分，并将其与发射特性相关联。讨论了通过金属有机气相外延（MOVPE）生长的两个具有高结构质量的样品，其铟的标称组分为x = 0.15和0.18。通过将扫描透射电子显微镜（STEM）图像与模拟结果进行比较，对局部铟成分进行定量评估，并从强度测量中提取局部铟浓度。计算结果指出，测得的铟波动可能与光致发光（PL）发射峰的宽化和强度降低有关。
