Growth of height-controlled InGaN quantum dots on GaN

InGaN height-controlled quantum dots (HCQDs) were grown by alternately depositing In0.4Ga0.6N QD and In0.1Ga0.9N spacer layers on a seed In0.4Ga0.6N QD layer. Structural and optical studies showed that the height of the InGaN QDs was controlled by the deposition cycle of In0.4Ga0.6N/In0.1Ga0.9N layers. Photoluminescence studies showed that the In0.4Ga0.6N HCQDs provided deep potential wells and the piezoelectric field-induced quantum-confined Stark effect was negligibly small. These phenomena are attributed to variation in quantum confinement energy in the electronically coupled InGaN HCQDs providing deep potential wells.