在這個實驗中，主要是研究晶界對於複晶矽薄膜電晶體可靠度的影響。所使用的樣本是由工研院以及友達光電所提供的。我們利用直流操作和交流操作這兩個模式去模擬複晶矽薄膜電晶體被使用後劣化的情況，利用電性方面的量測去研究晶界對於複晶矽薄膜電晶體劣化的影響。在連續橫向固體結晶複晶矽薄膜電晶體的實驗中，通道內有晶界的電晶體比較能夠抵抗直流的操作，但是卻較不能抵抗交流的操作。我們利用半導體元件模擬軟體的模擬結果來解釋這個現象

The influence of grain boundary (GB) on stability of poly-silicon thin film transistor (TFT) have been investigated in this work. The work was supported by the National Science Council of the Republic of China and AUO. We used ac stress and dc stress conditions to stress different TFTs, and investigate the influence of grain boundary by use of electrical analysis. The SLS poly-Si TFT which does contain GB perpendicular to the channel direction owns the higher ability against dc stress and poorer ability against ac stress than the poly-Si TFT which does not contain GB. The physical mechanism for these results has been reasonably deduced by use of TFT device simulation tool (ise-tcad).

Contents Chinese Abstract………………………………………………i English Abstract……………………………………………...ii Figure Caption………………………………………………..v Chapter 1 – Introduction 1.1 History ……………………………………………………..............1 1.2 Technology of Polysilicon Thin-Film Transistor………………...4 1.3 Leakage current of poly Si-TFTs and defects in poly-Si Film….5 References……………………………………………………………..7 Chapter 2 - Technology of Crystallization 2.1 Metal-induced Crystallization(MIC)…………………………….11 2.2 Excimer Laser Crystallization(ELC)…………………………….13 2.3 Sequential Lateral Solidification Crystallization……………….14 Reference………………………………………………………………19 Chapter 3 - Method of Trap Extraction 3.1 Defects in poly-Si film…………………………………………….22 3.2 Seto’s model……………………………………………………….23 3.3 deep-level transient spectroscopy………………………………..25 Reference……………………………………………………………...30 Chapter 4 - Results and Discusions
4.1 The Influence of DC Stress in SLS-Poly-TFT………………….33 4.2 The Influence of AC Stress in SLS-Poly-TFT………………….36 4.3 The Influence of AC Stress in ELA-Poly-TFT………………….37 4.4 Low Temperature Measurement………………………………...41 Reference……………………………………………………………...42 Chapter 5 - Conclusion 5.1 SLS Poly-TFT…………………………………………………….43 5.2 ELA Poly-TFT……………………………………………………43

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