GaN-on-GaN light emitting diodes (LEDs) have been considered to present the path towards ultimate LED technology. However, at present, the performance of the LEDs is still lower in comparison to GaN-on-sapphire LEDs. This work attempted to identify the possible factors that limit the performance of a GaN-on-GaN LED. To perceive this clearly, a GaN-on-patterned sapphire substrate (PSS) LED was also included in this study for comparison. It was found that the GaN-on-GaN LED exhibited lower performance (e.g. external quantum efficiency) than the GaN-on-PSS LED, especially at higher currents, despite its dislocation density being much lower than the latter. This is because the GaN-on-GaN LED had a lack of V-pits formation and carriers localization. As a result, the LED showed higher operating voltage and lower radiative recombination in comparison to the GaN-on-PSS LED.

GaN-on-GaN 发光二极管 (LED) 被认为是通往终极 LED 技术的道路。然而，目前，与蓝宝石基氮化镓 LED 相比，LED 的性能仍然较低。这项工作试图确定限制 GaN-on-GaN LED 性能的可能因素。为了清楚地认识到这一点，本研究中还包括了 GaN-on-patterned 蓝宝石衬底 (PSS) LED 以进行比较。发现 GaN-on-GaN LED 表现出比 GaN-on-PSS LED 更低的性能（例如外部量子效率），尤其是在较高电流下，尽管其位错密度远低于后者。这是因为 GaN-on-GaN LED 缺乏 V 坑形成和载流子定位。其结果，