為了改善低溫複晶矽薄膜電晶體電特性與穩定度，本論文以Fluorosilicate glass (FSG)覆蓋在通道層即複晶矽(Poly silicon, poly-si)上，在源極與汲極形成的同時，將氟離子驅入通道層內，形成Si-F鍵結，達到減少通道內缺陷的效果，由此改善元件特性與穩定度。我們進一步探討F離子濃度所造成的影響，在沉積FSG時，改變CF4氣體流量濃度，研究不同氟離子濃度對元件特性的影響，並在此論文中詳細討論。其次，因為傳統的N2電漿處理，是在元件完成後，氮離子較不容易穿透Passivation Layer達到通道層，故此論文另一項研究為使用中空陰極化學氣相沉積(Hollow-Cathode Chemical Vapor Deposition, HC-CVD)系統，直接對元件通道層做N2電漿處理，使氮離子可以直接進入通道層，形成Si-N鍵結，達到減少通道內缺陷的目的，且由於中空陰極管的原理，對通道層表面的傷害很小，相較於使用傳統高密度電漿化學氣相沉積(High Density Plasma Chemical Vapor Deposition, HDPCVD)系統之電漿處理，有較好的電特性表現。

In order to improve performance and reliability of low temperature poly-Si thin film transistors (LTPS-TFTs). In this thesis, the Poly-Si channel was covered with Fluorosilicate glass (FSG). When the source and drain were activated, the fluorine would drive-in the channel. It could reduce the trap in the channel so that it would improve the performance and reliability of device. We further studied the effects by the concentration of fluorine. When we deposited the FSG, we changed the flow of CF4 to investigate the influence of device with different concentration of fluorine. We would demonstrate in this thesis. It was difficult for nitrogen to through the passivation layer to reach the channel layer by traditional N2 plasma treatment. So we also used the HC-CVD system to treat the channel with N2 plasma. Hence the nitrogen could enter the channel to become Si-N bonds so that it could reduce the trap in channel. Due to the theorem of HC-CVD, the damage of channel surface was very small. It was better than used the HDPCVD to treat channel with N2 plasma. The HC-CVD system had better performance and reliability than the HDPCVD system.

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