近十幾年來科學家均專注於氮化鎵(GaN)在發光二極體之應用，而忽略了氮化鎵本身為寬能隙材料，具有高臨界電場的特性，可承受較高的偏壓。而且氮化鎵與氮化鋁鎵(AlGaN)所形成的異質接面會形成二維電子氣，該層電子具有高速電子傳導的優越特性，可應用於高速元件。同時氮化鎵的熱傳導優於矽(Si)材料，因此以氮化鎵為材料的高功率元件近幾年逐漸開始嶄露頭角。
本論文主要研究方向為，以矽為基板之氮化鎵與氮化鋁鎵磊晶片上，製作平面型高功率蕭特基二極體元件。透過製作流程的改善，製做出電特性穩定的蕭特基二極體。經由元件圖形的設計，探討蕭特基二極體元件不同陽極與陰極間距的差異對電特性的影響。論文中藉由歐姆接觸的優化，降低特徵接觸電阻(Specific contact resistance)；量測磊晶片本身的緩衝層漏電流與最高耐壓，了解磊晶片的品質；藉由製程順序的調整，降低元件逆向漏電流；最後製做具有場板設計的蕭特基二極體，提高了元件的耐壓(Breakdown voltage)。成功製做出崩潰電壓為1100V，導通電阻為3.55 mΩ-cm2，BFOM值為340.9 MW/cm2的高功率蕭特基二極體。

Gallium nitride is a wide bandgap material which have high critical electric field characteristics could withstand higher bias. In addition, two-dimensional electron gas with high transmission speed characteristics can be applied on high-speed device. Therefore, gallium nitride high power devices have rapid development in recent years.
The main objective of this study is to fabricate planar schottky barrier diode on GaN wafer. By improving the process flow to fabricate the schottky barrier diodes with stable electrical characteristics. Explore electrical characteristics by designing elements graphic which have different spacing between the anode and the cathode. In this study, we optimize ohmic contact to reduce specific contact resistance. Measure buffer layer leakage current to understand the quality of the epi-wafer. Finally, we fabricate a lateral schottky barrier diode with field plate design could increase the breakdown voltage of diode. The breakdown voltage of schottky barrier diode is 1100V, on resistance is 3.55 mΩ-cm2, and BFOM is 340.9 MW/cm2.

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