综述了国内外在LED钝化材料、钝化工艺和钝化处理对LED性能的影响等方面的一些主要研究进展,指出了以蓝宝石为衬底GaN基LED钝化材料存在的问题和研究方向,特别强调以Si为衬底的LED钝化膜的研究趋势。现阶段的钝化材料主要有SiNx、SiO2、SiONx等,常用的钝化方法有等离子体增强化学气相沉积(PECVD)、磁控溅射和电子束蒸发等。对LED芯片的钝化处理可以降低LED器件的漏电流和提高其光输出功率,然而,这也会导致LED的P区载流子数量的下降和芯片表面应力的增加。
This research concentrates on LED passivation materials,passivation process and the influence of the passivation to LED properties. At present, the popular passivation materials contain SiNx, SiO2 and SiONx. And the prevalent passivation methods are plasma enhanced chemical vapor deposition, sputtering, electron beam evaporation and so on. The passivation of LED chips can reduce the leakage current and increase its optical output power. However, this will reduce the number of LED carriers in the P-zone and increase the stress in the surface of LED chips.