利用雷射剝離法所製作的氮化鎵發光二極體已經被研究了七、八年，但是在發光強度及發光效率上一直沒有重大的突破。為了找出原因及製作高亮度的發光二極體，故作此研究。
實驗中發現，垂直式結構由於氮化鎵的磊晶層先天上缺陷，及經過雷射剝離法後所造成的應力釋放，會導致有很大的漏電流產生。另外，使用感應耦合電漿蝕刻也很容易造成側壁漏電流的產生。雖然很大的漏電流的產生會造成元件發光強度及發光效率的下降，但是由於發光面積比傳統製程來得大，故垂直式結構的發光二極體的發光強度比傳統發光二極體也來得強。
不只是亮度上有所提升，還有垂直式的發光二極體的波長漂移現象對注入電流的影響，遠比傳統式的發光二極體來得小很多。最後還有透過接觸溫度的量測，可以得知垂直式的發光二極體的接觸溫度相對來說也是比較低的。
雖然有很好的導熱性，但是應用於封裝體上，熱能一直累積在封裝體內進而影響元件的壽命時間。

The fabrication of the laser lift-off (LLO) GaN LED has investigated for 7~8 years, but there is no important breakthrough in light intensity and efficiency. In order to find out this reason and fabricate high brightness LED, this thesis is written.
Due to the natural dislocations in the GaN epilayers and released stress after LLO process, the strong leakage current occurs. Besides, the ICP process would also cause the leakage current of sidewall. Although the leakage current would make the light intensity and efficiency of the LEDs decay, the light intensity of vertical LLO LED is brighter than that of traditional LEDs because the area of light is larger.
There is not only the increase of light intensity but also the smaller red-shift effect compared the p-side-down and p-side-up LEDs with traditional LED. Finally, we could obtain that the junction temperature of p-side-down LED is relatively low during the junction temperature measurement.
There is good thermal conductivity in the LLO LED, but the thermal energy accumulate in the package. Therefore, it decreases the reliability of the LLO LED.

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