通过实验方法找出了去损伤刻蚀的最佳工艺参数,并研究了利用ICP两步刻蚀法去除刻蚀损伤的实验过程及结果.从实验结果可以看出,当ICP功率为750W时,刻蚀引入的损伤最小,刻蚀引起的损伤层厚度最大为25nm.去损伤刻蚀法能有效去除损伤,使采用两步刻蚀法的发光二极管的正向导通电压与反向漏电流均下降,发光亮度增大,非辐射复合比例减小,器件的发光效率和可靠性均得到了提高.
A two-step etching technology is used and the optimized etching parameter is found by experiment to remove etching damage in GaN-LEDs. The PL intensity of the sample etched by ICP with a power of 750W is decreased a little. The thickness of the etch damage layer is less than 25nm. The forward turn-on voltage and reverse leakage current of the LED that was etched by the two-step etching technology are reduced noticeably. The EL intensity is increased,indicating that the leakage current and the rate of nonradiative recombination both decreased. The optical efficiency and device reliability are also improved.