纳米光栅的表面等离激元增强型GaN-LED

为提高传统GaN基LED的发光效率，提出了一种基于纳米光栅结构的透射式表面等离激元增强型GaN-LED。该增强型LED包含覆盖在p型GaN光栅槽内的低折射率SiO2膜、Ag膜以及槽表面的ITO薄膜。详细阐述了该结构增强LED发光特性的基本原理，利用基于有限元法的模拟软件COMSOLTM-RF Module对该结构进行参数优化和数值模拟分析。研究结果表明，在周期p=280 nm，占空比f=0.5，SiO2层的厚度dSiO2=25 nm，银层的厚度dAg=15 nm，ITO层的厚度dITO=30 nm时，该结构在可见光范围内具有较高的传输效率，其零阶透射率高达0.716，零阶反射率为0.224，-1阶透射率峰值0.183，且Purcell因子增强了近16.4倍。该结构可以同时提高GaN基LED的内量子效率、光萃取效率和SPP萃取效率。

Surface-plasmon-enhanced GaN-LED based on nano-grating

In order to improve the luminous efficiency of conventional GaN-LED, a transmissive surface plasmon enhanced GaN-LED based on nano-grating was proposed. The enhanced LED included a low refractive index SiO2 film and a Ag film in the p-GaN grating slot, and the top layer ITO film. The basic principle of improving LED emission characteristics for this new structure was described in detail, and with simulation software COMSOLTM-RF Module based on the finite element method, the parameter optimization and numerical simulation analysis for the structure were studied. The results show that when the period p=280 nm, the duty ratio f=0.5, dSiO2=25 nm, dAg=15 nm, dITO=30 nm, the transmission efficiency of the structure is higher in the visible range, and the 0th order transmittance is 0.716, the 0th order reflectivity is 0.224, the peak of the -1st order transmittance is 0.183, with Purcell factor enhancing nearly 16.4 times. The internal quantum efficiency, light extraction efficiency and SPP extraction efficiency can be improved simultaneously in this new GaN-LED.