本論文結合了可撓式塑膠基板、奈米晶矽薄膜和熱鎢絲化學氣相低溫沉積，製作可撓式奈米晶矽薄膜電晶體。可撓式塑膠基板具有外型輕薄、價格便宜且可彎曲的特質。奈米矽晶薄膜特性介於多晶矽(poly-Si)與非晶矽(a-Si)之間，可低溫下(<250℃)大面積沉積，其不但具有非晶矽薄膜的製程簡單，大面積成長的優點，且具有多晶矽薄膜的高遷移率及驅動電流大的優勢。熱鎢絲化學氣相沉積法則是成長速率高(6.5nm/min)，製程簡單。
吾人利用聚碳酸酯(polycarbonate)和聚醯亞胺(polyimide)兩種可撓式基板材料，並研究不同製程，如將阻隔層平坦化，降低製成溫度（225℃）、縮短反應距離(4.5cm)和反應時間，製作奈米晶矽薄膜。並以場發射掃瞄式電子顯微鏡(FESEM)、原子力顯微鏡(AFM)檢測奈米晶矽薄膜表面形態，和用HP4145半導體參數分析儀，量測薄膜導電特性。結果發現聚醯亞胺基板較適合製作電晶體。以聚醯亞胺基板製作的可撓式奈米晶矽薄膜晶體，其開關電流比為1.16×103、場效遷移率為4.3(cm2/Vs)、臨界電壓為17.88伏特。這些結果不但堪與奈米晶矽薄膜晶體製作在傳統玻璃或矽基板上相比，而且較佳於傳統製作在玻璃基板上非晶矽電晶體。

In the thesis, we studied and optimized the different growing parameters such as using planarization barrier oxide, depositing temperature, and the distance between tungsten wire heater and substrate, and deposition time to prepare the nanocrystalline silicon thin films (nc-Si) on flexible plastic substrate by hot-wire chemical vapor deposition system (HWCVD). Both polycarbonate(PC) and polyimide(PI) were chosen as the flexible plastic substrate. The HW-CVD was adopted for its high deposition rate (6.5nm/min). Then, based on the optimized parameter, the nc-Si thin film transistors (nc-Si TFTs) were developed also on flexible plastic substrate. The nc-Si thin film has higher mobility and driving current than that of amorphous Si (a-Si) film, and can be uniformly deposited at low temperature (250℃). The film’s quality was examined with AFM and FESEM and I-V curve. The examination found the PI substrate is better for fabrication ns-Si TFT than the PC counterpart.
The ns-Si TFT on PI substrate, has current ratio of 1.16×103, drift mobility of 4.3(cm2/Vs), and the threshold voltage of 17.88(volt). These data are comparable to the ns-Si TFT on traditional Si or glass substrate, but are better than that of a-Si TFT on glass substrate.

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