Effects of strain on the characteristics of InGaN–GaN multiple quantum-dot blue light emitting diodes

In this study, Raman spectra were measured in the backscattering geometry at temperatures from 100 K to 298 K. Samples with the InGaN self-assembled quantum dot (SAQD) structures of high strain show a strong compressive stress in InGaN epilayer by Raman measurement. Furthermore, we have applied the dots-in-a-well (DWELL) structure to nitride-based light-emitting diodes (LEDs). It was found that EL peak variation of the LED with DWELL structure is more sensitive to the amount of injection current, as compared with the MQW LEDs.