InGaN/GaN blue light-emitting diodes with self-assembled quantum dots

InGaN/GaN blue light-emitting diodes (LEDs) with multiple quantum dot (MQD) active layers were successfully fabricated by using an interrupted growth method in metal-organic chemical vapour deposition (MOCVD). We have successfully formed nanoscale QDs embedded in quantum wells with a typical 3 nm height and 10 nm lateral dimension. It was found that a huge 68.4 meV blue shift in electroluminescence (EL) peak position as the injection current is increased from 3 to 50 mA for the MQD LED. The large EL blue shift reveals that deep localization of exitons (or carriers) originates from QDs will strengthen the band-filling effect as the injection current increases.