TCL+DBR与Ag+DBR倒装结构LED芯片光电性能比较

Comparison of Photoelectric Performance Between TCL+DBR and Ag+DBR Flip Chip LED

为给产业提供有效的参考,在同一的外延结构下,设计了TCL(透明导电层)+DBR(布拉格反射层)和Ag+DBR两种不同的结构倒装芯片,并实验对比两种结构的光电性能。结果显示:在500 mA的驱动电流下,相比于TCL+DBR结构的倒装芯片,Ag+DBR结构倒装芯片的输出亮度提升了8.7%,其饱和电流为1.32 A,比TCL+DBR结构的倒装芯片的饱和电流(1.16 A)高17.5%;同时,相比于TCL+DBR结构的倒装芯片,Ag+DBR结构的倒装芯片显示出更优的效率衰减性能。输出亮度、效率衰减性能的提升以及饱和电流的增加,主要归因于Ag+DBR结构的倒装芯片具有更佳的热分布效果、更宽的发光角度和更优的电流扩展效果。

TCL(transparent conductive layer)+DBR(Bragg reflector)and Ag+DBR were designed under the same epitaxial structure to compare the photoelectric performance of the two structures.The results show that the flip chip LED with Ag+DBR structure improves its output brightness by 8.7%at 500 mA drive current compared with the flip chip LED with TCL+DBR flip chip,its maximum LOP measured at 1.32 A is 17.5%more than that by the flip chip LED with TCL+DBR structured at 1.16A,and it has lower efficiency droop than flip chip LED with TCL+DBR structure.The improvement in output brightness,saturation current and efficiency attenuation performance are mainly attributed to the flip chip with Ag+DBR structure which has the property of better heat distribution effect,wider luminescence angle and better current expansion effect.