Effects of last barrier thickness on the hot-cold factor of GaN-based light-emitting diodes

The study of thermal properties for GaN-based light-emitting diodes (LEDs) with various last barrier thicknesses was reported. It was found that the LED output power decreased as we increased the thickness of the last barrier. It was also found that the LED output powers decrease with the increase of temperature for the LEDs with 12-, 24-, and 48-nm-thick last barriers. However, it was found that the LED output power increases with the increase of temperature for the LED with a 72-nm-thick last barrier due to the fact that more holes could enter the multiquantum well active region at elevated temperatures. Furthermore, it was found that the output power decreased by 0.15%/°C, 0.15%/°C, and 0.11%/°C for the LEDs with 12-, 24-, and 48-nm-thick last barriers, respectively, but increased by 0.09%/°C for the LED with a 72-nm-thick last barrier.