In order to improve the light extraction efficiency (LEE) of GaN-based light-emitting diodes (LEDs), a layer of cylindrical air-hole photonic crystal (PC) structure inserted into P-GaN is proposed and investigated numerically. Finite difference time domain (FDTD) method is used to make a series of simulations in the LEE of GaN-based LED with air-hole photonic crystal structure. According to the variable-controlling approach, the PC structure is simulated and optimized. The results of the simulations show that the LEE depends on the PC’s position and relevant structural parameters. When PC is etched in the active layer, and its dielectric constant Period=1μm, etching depth=0.2μm and air-hole radius r=0.28μm, higher LEE is obtained as 44.5%, translated into a 13.6-fold enhancement for the case of a planar LED. The remarkable enhancement is of particular interest for improving LEE of LED and provides a theoretical reference for future LED structure design efforts.

中文翻译：

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具有气孔光子晶体结构的 GaN 基 LED 的光提取效率

为了提高GaN基发光二极管（LED）的光提取效率（LEE），提出了一种插入P-GaN中的圆柱形气孔光子晶体（PC）结构并进行了数值研究。采用有限差分时域（FDTD）方法对具有气孔光子晶体结构的GaN基LED的LEE进行了一系列模拟。根据变量控制的方法，对PC结构进行了仿真和优化。模拟结果表明，LEE 取决于 PC 的位置和相关的结构参数。当PC在有源层被蚀刻时，其介电常数时期=1μ米，蚀刻深度=0.2μm 和气孔半径r=0.28μm，获得更高的 LEE 为 44.5%，对于平面 LED 的情况，转化为 13.6 倍的增强。显着的增强对于提高 LED 的 LEE 具有特别重要的意义，并为未来的 LED 结构设计工作提供理论参考。