Abstract: In order to solve the general problem of low extraction efficiency of conventional semiconductor light emitting diodes (LED), Gallium nitride (GaN)-based two-dimensional octagonal photonic quasicrystals (2D-8PQCs) structures were firstly fabricated and successfully applied on the GaN-based emitters by means of focused ion beam (FIB) etching. When the diameter of holes and air filling factor of 2D8PQC are 600nm and 30% respectively, the enhancement factor of the surface light extraction efficiency of the 2D-8PQC was achieved as high as 2.5 under current injection. The effects of 2D-8PQCs on the emitters were studied by the measurements of microscopic electrical luminescence and emitting images. It confirmes that the guided modes are blocked and coupled out into radiation modes by the 2D-8PQCs. The surface light extraction is consequently enhanced. It provides a promising way of the application of 2D-PQC to GaN-based light emitters.

Key words: GaN, two_dimensional photonic crystals, quasicrystals, focused ion beam etching, light extraction eficiency

摘要： 针对半导体发光管（LED）器件普遍存在的出光效率低下的问题，首次采用聚焦离子束技术成功地在GaN基发光器件上制备了GaN二维八重准晶光子晶体（2D-8PQCs）结构。并将二维八重准晶光子晶体应用于电注入器件，当刻蚀孔径为600nm，空气填充因子为30％时，得到了表面出光效率高达2.5倍的增强。通过微区电致发光与发光图样的研究，证实二维八重准晶光子晶体结构抑制了导波模式的传播，将LED中导波模式耦合到辐射模式，从而起到改进表面出光的作用。上述结果为二维准晶光子晶体在GaN基发光器件中的应用提供了一种可能的途径。

关键词: GaN, 二维光子晶体, 准晶, 聚焦离子束刻蚀, 出光效率