在這篇論文中，我們將研究低溫複晶矽薄膜電晶體（LTPS TFTs）在經過電性stress後的劣化機制，樣品為奇美公司所提供ELA TFTs；電性的stress可分為DC與AC兩種，首先，在DC stress方面，在固定汲極(drain)偏壓後，隨著閘極(gate)電壓的調變，所產生的劣化機制可分為兩種，分別為”熱載子效應”(hot carrier effect)以及”自我加熱效應”(self-heating effect)，我們將討論此兩種效應所產生劣化機制，另外，我們也用量測電容方式來區分所產生的缺陷種類及位置。

In this thesis, we will investigate the degradation of the Low-Temperature-Polycrystalline-Silicon TFTs(LTPS TFTS) under the electrical stress. The devices are offer by Chi Mei Optoelectronics. The two mechanisms of the electrical stress are ac and dc stress. On the dc stress, we can separate the two degradation mechanisms from fixed drain voltage and various the gate voltage. The first mechanism is hot carrier effect, and second is self-heating effect. We were study the degradation mechanisms cause by above-mentioned phenomenon. On the other hand, we were confirmed the position and type of the defects by measured capacitance.
In the ac stress, device degradation depends on the emission rate and energy of the hot carrier. We will study the degradation mechanism which fixed the drain voltage and various the Vg_low and falling time under different temperature. Another way of the ac stress condition will be used here. The drain and source are directly connected to ground. The gate is directly connected to the pulse. At this stress condition, carrier will push to the junction near the drain and source when gate pulse is switch from high to low. This degradation mechanism is the function of the temperature. We are going to employ a C-V measurement to examination of the defect cause by stress.

第一章 序論 1
1-1 概要 1
1-2 複晶矽薄膜電晶體應用於可曲饒式基版 3
參考文獻 4
第二章 元件製造及基本電性 7
2-1準分子雷射結晶技術 7
2-2 元件製造 8
2.3 複晶矽薄膜晶體基本特性 9
2.3.1 特性轉換曲線 9
2.3.2 複晶矽薄膜電晶體中缺陷 10
2.3.3 複晶矽薄膜電晶體的電容-電壓轉換曲線 12
2.3.4 Seto’ 模型 13
參考文獻 17
第三章 實驗儀器及參數粹取 20
3-1實驗設備 20
3-1-1實驗儀器 20
3-1-2 設置I-V量測平台 20
3-2 決定臨界電壓 21
3-3決定場效遷移率 23
3-4決定ON/OFF比例 23
3-5決定次臨界搖擺 24
3-6 決定平帶電壓 25
3-7 決定活化能 25
3-8決定陷阱密度 26
參考文獻 28
第四章 實驗結果與討論 29
4-1直流偏壓對低溫複晶矽薄磨電晶體的影響 29
4-2 低溫複晶矽薄膜電晶體自我加熱效應 30
4-2-1 自我加熱效應對低溫複晶矽薄膜電晶體所造成的劣化 30
4-2-2低溫複晶矽薄膜電晶體中電性的可逆行為 31
4-2-3 用量測電容方式來探討自我加熱效應後的劣化情形 31
4-3 閘極脈衝對低溫複晶矽薄膜電晶體的影響 33
4-4 交流偏壓效應與能態密度間關係 34
4-4-1實驗前的準備 34
4-4-2 交流偏壓效應對低溫複晶矽薄膜電晶體體所造成的劣化 34
4-4-3 電子捕獲與電子發射時間 35
4-4-4 電子發射與溫度間關係 36
參考文獻 38
第五章結論 39
圖示 40
表 格 72

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