论文部分内容阅读
在台面结构的GaN基发光二极管(LED)里,电流要侧向传输,当尺寸与电流密度加大之后,由于n型GaN层和下限制层的横向电阻不能忽略,造成了横向电流分布不均匀.通过优化电极结构,以减小电流横向传输距离,制作出两种不同电极结构的大功率GaN基倒装LED.通过比较这两种不同电极结构的GaN基倒装大功率LED的电、光性能,发现在350mA正向电流下,插指电极结构的倒装大功率GaN基LED的正向电压为3.35V,比环形插指电极结构的倒装大功率GaN基LED高0.15V.尽管环形插指电极结构GaN基LED的发光面积略小于插指电极结构GaN基LED,但在大电流下,环形插指电极结构倒装GaN基LED的光输出功率比插指电极结构的倒装大功率LED的光输出功率大.并且在大电流下,环形插指电极结构的倒装大功率LED光输出功率饱和速度慢,而插指电极结构的倒装大功率LED光输出功率饱和明显.这说明优化电极结构能提高电流扩展均匀性,减小焦耳热的产生,改善GaN基LED的性能.
In a mesa GaN-based light-emitting diode (LED), the current should be transferred laterally. When the size and current density are increased, the lateral current distribution is not uniform due to the inability to ignore the lateral resistance of the n-type GaN layer and the lower confinement layer By optimizing the electrode structure to reduce the current transverse transmission distance, two kinds of high-power GaN-based flip-chip LEDs with different electrode structures were fabricated.Through comparing the two different electrode structures of GaN- Performance and found that at 350mA forward current, the forward voltage of the flip-chip high power GaN-based LED with the interdigital electrode structure was 3.35V, 0.15V higher than the flip-chip high power GaN-based LED with the ring finger electrode structure. Although the ring Interposer electrode structure GaN-based LED light-emitting area slightly smaller than the interdigital electrode structure GaN-based LED, but under high current, the annular interdigital electrode structure flip-GaN-based LED light output power than the flip-chip electrode structure flip-flop high power LED light output power. And under high current, ring finger electrode structure of the flip-chip high-power LED light output power saturation slow, and the interdigital electrode structure flip-high power LED light output saturation. Optimize electrode structure High current spreading uniformity, the Joule heat is reduced, improving the performance of GaN-based LED.