高效大功率LED用蓝宝石图形衬底制备的研究进展

Research progress in the preparation of patterened sapphire substrates for high-efficiency and high-power GaN-based LEDs

近年来,图形化的蓝宝石衬底在改善GaN晶体外延生长质量以及提升LED器件发光提取效率方面作用显著,引起了广泛的研究兴趣。综述了蓝宝石图形衬底的制备方法(干法刻蚀、湿法刻蚀、外延生长法),并较系统地介绍了蓝宝石图形衬底表面周期性图形参数(图形形貌、图案尺寸、图形占位比及其深度)对LED发光薄膜及器件的影响及其机理,最后对蓝宝石图形衬底的发展趋势进行了展望。

Patterned substrate sapphire has attracted much interest in recent years due to its outstanding properties in improve GaN epitaxial crystal quality and light output powers of the LEDs. The fabrication methods of patterned substrate sapphire are reviewed, including dry etch, wet etch and epitaxial growth method. The relationship between the mechanism of improve epitaxial crystal quality and morphology of the patterned substrate sapphire （grooves, micron hole, micron columnar, micron hemispherical, nano-hole and nano-columnar） is also discussed.