An InGaN/GaN single quantum well improved by surface modification of GaN films

Surface modification of GaN films by in situ droplet homoepitaxy of thin GaN layers was employed for improvement of the surface/interface qualities characterized by atomic smoothness, low defect density and surface chemistry being close to stoichiometry. We find that, with surface modification of the GaN films the surface morphology of the subsequently grown InGaN/GaN single quantum well (SQW) was improved with less density of surface pits and indium-rich inclusions. The improvement in surface smoothness and InGaN/GaN surface/interface qualities is desirable for the growth of high-quality multiple QWs (MQWs) structures and fabrication of high-performance and reliable LEDs. PL results show that with surface modification the QW luminescence was significantly enhanced by more than 50% than that without surface modification.