Real-time studies of In-adlayer during PAMBE of InGaN/GaN MQWs



The control of In adlayer during plasma-assisted molecular beam epitaxy (PAMBE) of InGaN/GaN multiquantum wells (MQWs) is critical to achieve good structural and optical properties. This contribution focuses on the investigation by real-time spectroscopic ellipsometry, corroborated by reflection high energy electron diffraction (RHEED), of In adlayer during the PAMBE growth of InGaN/GaN MQWs. The ellipsometric data reveal In accumulation during InGaN growth, which results in thicker quantum well than designed. We address the effect of the indium adlayer on the growth of InGaN/GaN with an indium composition between 7% and 13%, and on their optical and structural properties determined by high-resolution X-ray diffraction and photoluminescence. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)