摘要
采用图形化蓝宝石衬底(PSS)技术可以降低GaN外延层材料位错密度,提高了发光二极管(LED)的内量子效率(IQE),同时使LED光析出率(LEE)提高。基于PSS技术可以制作高效GaN基高亮度LED。基于已公开发表文献对用于高效LED制作的PSS技术做了综述,介绍了PSS技术演化、PSS的制作方法与主要的图形结构、PSS上GaN外延层生长机制以及PSS对LED性能的影响。PSS结构对LED的IQE与LEE均有提高,但对二者哪个提高更为有效没有定论,最近的研究结果倾向于以为对LEE提高更为有效。PSS对LED的IQE与LEE提高的机制目前并不是非常清楚,对公开发表的PSS对LEE的提高机制提出了不同看法。不同PSS结构与尺寸对GaN质量以及LED性能的影响方面的研究目前还非常缺乏。
Based on patterned sapphire substrate （PSS） technique, threading dislocations density （TD） in GaN epilayer can be reduced and the internal quantum efficiency （IQE） as well as light extraction efficiency （LEE） of light emitting diode （LED） can be improved. Highly efficient LED based on GaN can be grown on patterned sapphire substrate. A review of PSS technique is given based on published papers, including the development of PSS technique, its fabrication and pattern structure, process of GaN epilayer growth and performance improvement of LED on PSS. IQE and LEE can both be improved by PSS, but it is unknown that improvement from IQE or LEE achieved by PSS is essential. The mechanism of improvement of IQE and LEE is not very clear, while arguments about the mechanism proposed by published papers are given. The effects of different PSS structures and sizes on the quality of GaN and performance of LED are not well investigated yet.
出处
《激光与光电子学进展》
CSCD
北大核心
2012年第8期35-43,共9页
Laser & Optoelectronics Progress
基金
国家科技重大专项(2009ZX02037)资助课题
关键词
材料
图形化蓝宝石衬底
发光二极管
内量子效率
GAN外延生长
光析出率
materials
patterned sapphire substrate
light emitting diodes
internal quantum efficiency
GaN epitaxy growth
light extraction efficiency
