非晶矽薄膜電晶體(Amorphous Silicon Thin Film Transistor,a-Si TFT)製程簡單但是因為電子移動率不佳導致元件電性不良；低溫多晶矽薄膜電晶體(Polycrystalline Silicon Thin Film Transistor, poly-Si TFT)雖然有優越的特性但是製程較繁瑣且成本較高。而奈米晶矽薄膜 (Nanocrystalline Silicon, nc-Si)擁有比非晶矽薄膜電晶體佳的電性並且製程比低溫多晶矽薄膜簡單，故成長奈米晶矽薄膜是一項非常有前瞻性的技術。
在各種沉積奈米晶矽薄膜的技術裡熱絲化學氣相沉積 (Hot-Wire Chemical Vapor Deposition, HWCVD)因為擁有高沉積速率與低成長溫度因此特別受到重視。在本論文中我們用HWCVD在玻璃基板上以成長溫度2500C、成長速率3.4nm/s下沉積奈米晶粒薄膜，並以場發射掃瞄式電子顯微鏡(FESEM)、原子力顯微鏡(AFM)、X光繞射儀(XRD)、拉曼光譜儀(Raman Spectroscopy)、霍爾量測儀(Hall measurement)等儀器來分析各種參數如鎢絲溫度、氫氣濃度、基板溫度對薄膜結晶性的影響。最後我們成功以HWCVD研製出奈米晶矽薄膜電晶體，其場效電子移動率約為3.4cm2/V•S比非晶矽薄膜電晶體優越。

Recently amorphous thin film transistor (a-Si),low temperature poly-Si TFT ,and nanocrystalline TFT(nc-Si TFT) have been studies widthly for flat panel display. However the fabrication process of amorphous silicon thin film transistor (a-Si TFT) is simple but it’s performances are low for electric mobility. Although low temperature polycrystalline silicon thin film transistor(poly-Si TFT)shows higher mobility than a-Si TFT, but it also possecess the high fabricating cost and complicated process. Only nanocrystalline silicon TFT(nc-Si TFT) shows better electric characteristics than a-Si TFT and easier fabricating process than poly-Si TFT.
On the other hand, hot wire chemical vapor deposition (HWCVD) has been developed as a attractive technique for deposition of thin film nanocrystalline silicon films with low temperature and high deposition rate. In this thesis we present experimental results on HWCVD deposited nc-Si film on glass between 2500C at growth rate of 3.4nm/s.The influence of the deposition conditions such as temperature of filament, temperature of substrate, and hydrogen dilution on the material crystallinity were analyzed through FESEM, AFM, XRD, Raman Spectroscopy and Hall measurement. Additionly we have successfully fabrication nc-Si TFT with better field effect mobility about 3cm2/V•S than a-Si TFT.

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