纳米压印技术制备表面光子晶体LED的研究

A study of LED with surface photonic crystal structure fabricated by the nanoimprint lithography

利用表面光子晶体能大幅提高发光二极管(LED)的外量子效率,但如何制备大面积的纳米光子晶体是该研究方向的主要难点之一.本文基于纳米压印技术在氮化镓基发光二极管(GaN-LED)表面制作孔状二维光子晶体.通过以金属和聚合物双层掩膜干法刻蚀法,得到了很好的光子晶体图形转移效果.最终在LED的p-GaN层表面获得了大面积光子晶体,周期为450nm,纳米孔直径为240nm.器件测试结果显示,有表面光子晶体的LED比没有光子晶体的LED,光致发光强度峰值提高到了7.2倍.

Surface photonic crystal （PC） structure can improve the external quantum efficiency of light-emitting diode （LED）. However, it is very difficult to fabricate large area and uniform nanometer photonic crystal structure in this field. In this paper, two-dimensional PC with hole-like structure is successfully transferred to the surface of gallium nitride LED （GaN-LED） by the mental-polymer double-layer mask dry etching technology combined with the nanoimprint lithography. The large area nanometer PC patterns with pore diameter of 240 nm and period of 450 nm are obtained. The results show that the photoluminescence peak intensity of LED with the PC structure is 7.2 times higher than that of the conventional LED.