本研究多通道AlGaN/GaN高電子遷移率場效電晶體藉由干涉雷射曝光搭配光電化學法完成製作，以光電化學濕式蝕刻法蝕刻多通道能降低元件以反應式離子蝕刻機進行離子轟擊所造成的缺陷，並以光電化學氧化法直接生長氧化層當作閘極絕緣層與表面鈍化層。
平面式單通道結構與多重通道結構(線寬為500 nm)比較，平面式結構在汲源極電壓(VDS)為10 V和閘源極電壓(VGS)為5 V下，汲源極飽和電流(IDSS)為493 mA/mm，而多通道結構在汲源極電壓為6 V和閘源極電壓為5 V下，汲源極飽和電流為290 mA/mm，而平面式結構與多通道結構之轉導特性分別在汲源極電壓為10 V與6 V時，最大轉移電導值(gm(max))分別為91.3 mS/mm與128 mS/mm，比較平面式結構與多重通道結構可發現臨界電壓(Vth)從-2.3 V至-0.6 V往正偏移，膝點電壓(knee voltage)從10 V變小至6 V與次臨界擺幅(subthreshold swing)也從370 mV/dec降低至189 mV/dec，在RF特性上最大震盪頻率(maximum oscillation frequency, fMax)有所提升。
再進一步比較線寬為500 nm與200 nm多通道架構，當通道寬度減小，臨界電壓正偏移至-0.4 V，膝點電壓縮小為4 V，最大轉移電導值提升到197 mS/mm，次臨界擺幅則下降至116 mV/dec，閘極漏電流更有效的減少至5.89×10-9 A，最大震盪頻率隨通道寬度遞減也有改善，在此結構下形成的三面閘極結構因比平面式結構多了兩邊之側向電場效應在二微電子氣邊緣，故有效提升閘極控制能力並有較低之膝點電壓與使臨限電壓正偏移。當通道寬度縮減時，環繞電場效應更加明顯，更有效地控制二微電子氣密度，將進一步提升閘極控制力，並使漏電流減少，加快元件切換速度。

In this research, multiple-channel structured AlGaN/GaN metal-oxide-semiconductor high-electron-mobility transistors were fabricated by using laser interference photolithog-raphy method and photoelectrochemical method. Photoelectrochemical method can avoid damage than that used by RIE. The photoelectrochemical oxidation method can grow ox-ide on the AlGaN layer as gate dielectric film and passivation of the surface. Compare planer structured, we can obviously find the threshold voltage toward the positive bias direction. The drain-source saturation voltage, gate leakage current, subthreshold swing, maximum transconductance and the maximum oscillation frequency are improved.

第一章 簡介
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第二章 原理與文獻回顧
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第四章 實驗結果與討論
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