Abstract
Differences in optical and structural properties of indium rich (27%), indium gallium nitride (InGaN) self-organized quantum dots (QDs), with red wavelength emission, and the two dimensional underlying wetting layer (WL) are investigated. Temperature dependent micro-photoluminescence (mu PL) reveals a decrease in thermal quenching of the QDs integrated intensity compared to that of the WL. This difference in behaviour is due to the 3-D localization of carriers within the QDs preventing them from thermalization to nearby traps causing an increase in the internal quantum efficiency of the device. Excitation power dependent mu PL shows a slower increase of the QDs PL signal compared to the WL PL which is believed to be due to the QDs saturation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4751434]