GaN based hot electron light emitting heterojunction

In this study, optical properties of InGaN/GaN multiple quantum well structures which are used in the production of electronic and optoelectronic devices have been investigated. The samples with different quantum well numbers and indium concentration were grown on sapphire (Al2O3) substrate. In the first part of the optical measurements, to investigate emission mechanisms of InGaN/GaN multi quantum well structures, the temperature dependence of photoluminescence measurements was carried out between 3 and 300K. The temperature dependence of emission peak energy and GaN barrier peak energy that observed in the photoluminescence spectra were analysed by supporting Varshni and Band Tail models. The effect of the quantum well number and In concentration on these parameters were investigated. In the second part of the study, the temperature dependence of Raman measurements were performed. In the obtained spectra, longitudinal optical phonon energies of InGaN/GaN multiple quantum wells were determined. The obtained results were evaluated by comparing with the literature.