Optical Properties of InGaN/GaN Multiple Quantum Well Structures Grown on GaN and Sapphire Substrates

Abstract

A set of samples based on InGaN/GaN multiple quantum well (QW) structures with an extremely thick active region and high QW numbers was prepared on different substrates by metal organic vapor phase epitaxy. Their morphology was studied by SEM images, and their optical properties, including photoluminescence (PL) excitation, PL emission spectra, and PL decay curves, were measured by means of time-resolved luminescence spectroscopy. The obtained spectral features were tentatively explained by using the band scheme, which is commonly used for the description of InGaN/GaN multiple QW (MQW) structures. The application potential in the field of nanoscintillators used for fast timing of studied structures is discussed as well.