ZnO纳米棒阵列提高发光二极管光抽取效率的研究

Enhanced Light Extraction Efficiency of Light-Emitting Diodes with ZnO Nanorod Arrays

为了提高大功率LED的光抽取效率,采用溶胶-凝胶法、水热生长法的两步生长工艺在大功率红光发光二极管(LEDs)表面制作ZnO纳米棒阵列结构进行研究。利用ZnO纳米棒形成的光波导,ZnO纳米棒侧面为辅助出光面,提高了LED芯片的光输出效率。测试表明,所生长的ZnO纳米棒分布密度均匀,形貌一致;与未制作ZnO纳米棒前相比较,LED的电流-电压特性与发光光谱未发生明显变化;当输入电流为310mA时,光抽取效率提高约15%。

To increase the light extraction efficiency of high-power light-emitting diodes （ LEDs）, ZnO nanorod arrays were prepared by utilizing sol-gel coating and the aqueous solution growth technique successively. ZnO nanorod arrays were used as waveguides for emitting light and light emission from LED could escape via the side walls of the ZnO nanorods. ZnO nanrod arrays have uniform size distribution and morphology. Current-voltage characteristics and electroluminescence measurements indicated that there was no significant change in electrical and optical properties of the LEDs with ZnO nanorod arrays. With 310mA current injection,the light output efficiency of the LED with ZnO nanorod arrays was enhanced by about 15%.