MOCVD growth and optical study of InGaN quantum dots and their emitters on a high quality GaN layer grown using a high temperature AlN as buffer

The optical properties have been investigated on InGaN quantum dots (QDs) with density up to 9x 10(10)/cm(2) and excellent uniformity grown on a high quality GaN surface grown using high temperature AlN as a buffer layer on sapphire. A stimulated emission from the multiple layers of InGaN QDs has been observed under an optical pumping with a low threshold at room temperature indicating a superior optical quality. Moreover, InGaN QD based light emitting diodes (LEDs) with good performances have been grown and fabricated, and then the influence of the thermal annealing for p-type GaN activation on the optical properties of the InGaN QD based LEDs has been studied. It has been found that the optimized annealing conditions for p-type GaN activation can lead to significantly improved performance of the InGaN QD based LEDs. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim