本論文主旨在進行具有電流阻障層之鍍鎳基板垂直結構GaN-基LED之研製。配合實驗之製程，本研究使用ISE模擬軟體進行元件電性模擬分析，由模擬結果可以看出，電流阻障層之配置已成功將電極下方之電流擴展至電極四周。我們將磊晶層利用ICP蝕刻出電極大小之區域，之後使用PECVD沉積SiO2層，使用E-Beam製備附著與反射層，進行電鍍鎳基板，搭配區塊雷射剝離技術(Patterned Laser Lift-off)置換藍寶石基板，成功製作出具有電流阻障層之垂直結構12 mil LED。
實驗結果顯示，雖然具電流阻障層之垂直結構LED之順向壓降比無電流阻障層者稍增加0.1 V(@20 mA)，串聯電阻約上升1~2 Ω，然於20 mA工作電流下之光輸出功率，可比沒有電流阻障層之元件提升47.3%，其power efficiency可改善40%。於試片表面粗化部份，使用浸泡KOH溶液濕蝕刻，以進一步增加光輸出功率，結果顯示浸泡KOH 90 s，於20 mA工作電流條件下可得到最佳光輸出功率，增加59.5%，並使順向壓降減少0.1~0.2 V。本研究顯示具有電流阻障層之垂直結構元件，對增加LED光特性方面有明顯之助益，而經過表面處理，更能增加外部量子效率。

In this study, the performance of vertical-structured metallic substrate GaN-based light-emitting diodes (VM-LEDs) with a current blocking layer (CBL) was investigated. Nickel electroplating and patterned laser lift-off (LLO) techniques were employed for the transfer of sapphire substrate to Nickel substrate. The simulation for proposed LED structure was made by the use of ISE software, showing a great effect upon the current blocking under the n-pad. In experiments, through the etching by inductively coupled plasma (ICP), deposition of SiO2 by PECVD, evaporating adhesive/mirror layer by E-Beam, Ni-plating process, incorporating with patterned laser lift-off technology to remove the sapphire substrate, the vertical structure 12-mil VM-LED with current-blocking layer was fabricated successfully.
As compared to the VM-LEDs without a CBL, the use of proposed CBL structure leads to the higher forward voltage drop and series resistance by 0.1 V (@20 mA) and 1~2 Ω, respectively. However, under the injection current of 20 mA, the VM-LEDs with a CBL exhibits an increase in light output power (LOP) by 47.3%, as compared to the VM-LEDs without the CBL structure. Moreover, the improvement of LED performance by the use of KOH chemical treatment upon the sample surface was also demonstrated. With ICP etching followed by an additional KOH treatment for 90 s on the n-GaN layer, an increase in LOP by 59.5% and a decrease in forward voltage drop by about 0.1~0.2 V at 20 mA have been achieved for the proposed VM-LEDs with a CBL.

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