本論文提出具有低暗電流與高光電流的PIN二極體，透過元件的電性與光性提升光感應器的效能，使電路設計簡單化，並將新式光感應器設計於3T主動式影像感測器電路，期望將觸碰式面板整合於LTPS面板中。首先，此新元件採用雙閘極絕緣層製程，利用SiNx自我氫化的效果使暗電流降低。第二部分透過減少光線損失、增加單位面積光子數與增加空乏區長度，達到增加光電流的功效。其中靈敏度最高的元件為在本質區上方空洞並鋪上ITO電極的PIN二極體，在波長555nm、照度70lux和逆偏壓3V的條件下，此元件之靈敏度為204fA/lux，相同條件下之傳統PIN二極體，其靈敏度為41fA/lux。透過以上降低暗電流與提升光電流的方法，在電路設計上將有更大的空間實現整合於LTPS製程中之觸碰面板系統。

Novel LTPS PIN photo detectors with low dark current and high sensitivity have been developed. Dual gate insulator including TEOS and SiNx layer are employed to enhance hydrogen level which can effectively repair defects in the poly-Si thin film and in turn reduces dark current level in the PIN device. To increase photo responsibility, structural layer on top of the photo-detector is designed to reduce light loss. A hollow region is etched and filled with ITO to enhance light penetration to the depletion region. Bias voltage added to the ITO electrode is demonstrated to increase the depletion region of the device, which lead to better photo responsibility. By the above methods, we successfully develop a high performance PIN diode.

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