當近年來的TFT-LCD的產業趨向發展大面積,高解析度的AM-LCD時，同時遇到了一些問題。當TFT-LCD尺寸變的更大，解析度越高時，閘極金屬的電阻及電容帶來的問題已經不可忽略了。其中包括了影像失真，最簡單的解決方法是使閘極導線更厚且更寬，但會使對比度降低。因此，應用低阻值材料銅作為閘極金屬對於解決RC delay是一種選擇。除此之外，銅的電子遷移率的活化能高達0.97eV，所以對電子遷移有較好的抵抗性。
但是使用銅當作閘極材料也會遇到一些問題:對玻璃基板的附著性差，蝕刻的難度等諸多困難。
本研究裡，利用Cu與CuMg兩層金屬作為非晶矽薄膜電晶體的閘極及源極汲極金屬已經成功被開發。我們引入Cu與CuMg合金克服銅與玻璃基板的附著性問題。而且，一種在傳統電路板使用的酸成功作為蝕刻出銅閘極形狀的溶液，蝕刻出的銅金屬形狀正是閘極金屬需要的坡度形狀，且蝕刻誤差甚小。實驗結果顯示，我們成功製造出具優異特性的非晶矽薄膜電晶體。
對於非晶矽薄膜電晶體在關閉狀態時源自光漏電的訊號誤差，我們利用氧化銦錫(ITO)來取代傳統薄膜電晶體結構中的源極與汲極作為有效的抑制方法。在光強度3300cd/m2的背光源下，光漏電表現出一種明顯的轉換。在本文中，我們將會對源極與汲極的能帶作一討論。

In the recently TFT-LCD fabrication demands, some problems exist while developing large-area AM-LCD with high resolution. As TFT-LCD becomes larger in size and higher in resolution, we can not neglect the influence brought by resistance and capacitor of gate. So that incomplete image comes up but it can be solved by making thicker and wider lines at a loss of aperture ratio. Therefore, applying copper with low resistivity property material be gate metal is a way to resolve RC delay (Resistance Capacitor Delay). And then copper has better resistance to electro-migration because its activation energy of electro-migration reaches about 0.97eV.
But taking copper as gate material also encounters some problems: poor adhesion to glass substrates, etching method etc...
The feasibility of using Cu/CuMg as a gate electrode and a source/drain metal for a-Si:H TFT has been investigated in this work. The issue of adhesion between the Cu film and glass substrates has been overcome by introducing the Cu/CuMg alloy. Furthermore, a wet etching process of Cu-based gate metal has been proposed by using the copper etchant in the conventional printed circuit boards (PCBs). The experimental result showed superior performance of a-Si:H TFT with desired electrode taper angle and minimal loss of critical dimension.
In addition, for effectively reducing the off-state signal loss resulted from the a-Si:H TFTs photo leakage current, the a-Si:H TFTs with the use of ITO as source-drain metal have been fabricated for this study. A remarkable transformation in photo leakage current has been observed under the 3300cd/m2 CCFL backlight illumination. The source-drain barrier height engineering has been proposed for this study.

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