2162-8769/2013/2(12)/R267/6/$31.00 © The Electrochemical Society Effect of Barrier Growth Temperature on the Material Properties of InGaN/GaN Multiple Quantum Well Structures

InGaN/GaN multiple quantum well (MQW) structures with different GaN barrier growth temperatures have been grown by metal-lorganic chemical vapor deposition (MOCVD) and investigated. Double peak InGaN emission was observed and correlated to the barrier growth temperature. It was deduced that the extra emission peak originated from InGaN/GaN nanostructures formed around (VGa-ON)2 − point defects mainly at the bottom wells of MQW stack, due to local strain relaxation in the vicinity of point defects and the compositional pulling effect on In. Increasing barrier growth temperature decreases O impurity incorporation and thus prevents the formation of an undesired radiation source in the active layer which decrease the quantum efficiency