Time-resolved photoluminescence study of InGaN MQW with a p-contact layer

To clarify the influence of diffused Mg impurities on the carrier recombina tion in InGaN multiple quantum wells (MQWs), we have performed a systematic study using time-resolved photoluminescence (PL) measurements. It was foun d that the MQWs with a p-contact layer and the MQWs with a nondoped GaN lay er had almost the same carrier lifetime and PL intensity below 200 K. Howev er, the MQWs with the p-contact layer had shorter carrier lifetime and lowe r PL intensity than the MQWs with the nondoped GaN laver above 200 K. This degradation of the PL for the MQWs with the p-contact laver can be attribut ed to nonradiative recombination caused by the diffusion of Mg impurities f rom the p-contact laver into MQWs.