Abstract
Self-organized InN quantum dots were grown on GaN(0001) by metal–organic vapour phase epitaxy. Transmission electron microscopy (TEM) measurements found no wetting layer, i.e., the dots grow directly in Volmer–Weber growth mode. The dots were capped with GaN by three different procedures. Direct overgrowth at the same temperature as the dot formation produced the smoothest surfaces. Cubic and hexagonal GaN was observed in the cap layer, as well as strong indium intermixing. The dot size and volume was reduced during overgrowth. The dots were ∼90% relaxed with many dislocations at the interface from GaN to InN. The photoluminescence of the dots was very weak due to the dislocation.