Study on Carrier transportation in InGaN based green LEDs with V-pits structure in the active region

摘要

InGaN based LEDs with V-pits structure and consists of n-GaN, In0.1Ga0.9N/GaN superlattices (SLs), In0.25Ga0.85N blue quantum wells (BQWs), In(0.25)G(a0.75)N green quantum wells (GQWs) and p-GaN were grown on Si substrate. Carrier transportation is studied by temperature-dependent electroluminescence (TDEL). With n-doping in the SLs and BQWs, the major emission peak is from the GQWs. Under low temperature and high injection current, side peaks emitted form SLs and BQWs can be observed. Reducing the number of GQWs will result in stronger side peaks. We propose that the disequilibrium in carrier concentration bring high drift velocity to the holes, partial holes fly across the sidewall of V-pits to n-side and recombined with the electrons in the BQWs and SLs.