本論文中，我們成功製作全透明的高電子遷移率電晶體(high electron mobility transistor, HEMT)。相較於傳統的非透明Ni/Au閘極HEMT，我們以矽離子佈植的方式形成N型歐姆接觸來達到元件透明的目的。為了確保全透明HEMT的光穿透率，我們將傳統Ni/Au閘極HEMT常使用的Ti/Al/Ti/Au合金改為氧化銦錫(indium tin oxide, ITO)薄膜，閘極的部分也從Ni/Au金屬閘極改為ITO蕭特基式閘極。
實驗中我們發現在經過600°C的高溫熱退火後，ITO薄膜的阻值得到改善並擁有相當高的光穿透率。全透明HEMT在閘極偏壓於1V時，其最大飽和電流值可以達到 223 mA/mm。試片在可見光波段中具有70%以上的光穿透率，而場效電子遷移率(field effect mobility)最大值可以達到860 cm2/ V·s。以上結果展現出全透明HEMT在光電、顯示與感測器技術上具有相當的發展潛力。

In this thesis, we demonstrate a fully transparent AlGaN/GaN high electron mobility transistor. Comparing with the conventional non-transparent Ni/Au gate HEMT, N-type ohmic contact by using silicon ion implantation is created for transparency. To ensure the high transmittance of the fully transparent HEMT, Ti/Al/Ti/Au alloyed metal stack and Ni/Au metal gate which are commonly used in conventional Ni/Au gate HEMT are both replaced by indium tin oxide (ITO) layer.
After 600°C annealing treatment, the ITO layer shows an improved resistivity and a high transmittance. The maximum output current is 223 mA/mm at a gate voltage of 1V. The transmittance of the fabricated chip is over 70% in the visible spectrum range, and the field effect mobility is as high as 860 cm2/ V·s. These results indicate the great potential of the fully transparent HEMT for optoelectronics, display technologies and sensing.

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