我們利用準分子雷射結晶、橫向連續結晶與熱滯留輔助結晶的方式
製造薄膜電晶體。在交流電壓與熱載子的可靠度分析下，以熱滯留輔助結晶方式製造薄膜電晶體有比較好的可靠度。在趨饒方面，以橫向連續結晶方式製造的薄膜電晶體比準分子雷射結晶方式製造的薄膜電晶體有更明顯的變化，這提供我們在製造可趨饒的液晶顯示器的一個好的選擇。在光電流方面，如果在通道中有大的晶界，光電流就會有明顯的下降。不論在製程或是量測的參數下，以熱滯留輔助結晶的方式製造薄膜電晶體都有比較好的表現；但是，他也是有缺點必須去克服—我們必需多成長一層熱滯留層，也必須蝕刻掉它、複晶矽與熱滯留層的蝕刻比…等等。

There were three poly-Si TFT made by ELA, SLS, and HREC. The HREC TFT had better reliability than ELA TFT and SLS TFT under AC and hot carrier stress. And the effect of bending in SLS TFT was more obvious then ELA TFT, it provide us a better choose to develop a flexible TFT LCD.
In poly-Si TFT, the photon current would decrease if there was a grain boundary in the channel. In all parameters include both manufacture and measurement the HREC TFT had better behaviors than ELA TFT and SLS TFT. But there also some shortcomings we must overcome include we muse
growth a heat-retaining layer extra and must etch it and the poly-Si/heat-retaining etch rate and so on.

Chinese Abstract I
English Abstract II
Contents III
Figure Caption V
Table Caption IX
Chapter 1 – Introduction 1
1.1 Overview 1
1.2 Technology of polycrystalline-silicon thin-film transistor 3
1.3 Defects in polycrystalline-silicon film 4
1.4 Seto，s model 5
Chapter 2 - Technology of crystallization 9
2.1 Excimer laser crystallization(ELC) 9
2.2 Sequential lateral solidification crystallization(SLS) 10
2.3 Heat-retaining enhanced crystallization(H-REC) 15
Chapter 3 - Fabrication and electrical characterization 17
3.1 Device fabrication 17
3.1.1 Fabrication of Excimer laser crystallization(ELC)
TFT 17
3.1.2 Fabrication of Sequential lateral solidification
crystallization(SLS) TFT 17
3.1.3 Fabrication of Heat-retaining enhanced
crystallization(H-REC) TFT 18
3.2 Basic characterization of the LTPS TFT 19
3.2.1 Transfer characteristics 19
3.2.2 Output characteristics 21
3.3 Method of device parameter extraction 22
3.3.1 Determination of the threshold voltage 23
3.3.2 Determination of the field-effect mobility 25
3.3.3 Determination of on/off current ratio 26
3.3.4 Determination of the subthreshold swing 26
3.3.5 Determination of the trap density 27
3.3.6 Determination of the channel resistance and the
parasitic resistance 28
Chapter 4 - Results and Discussions 30
4.1 The Influence of AC stress 30
4.1.1 Capacitance measurement with variable frequency
---determination of the energy of trap 31
4.1.2 Saturation operation
---determination of the position of trap 32
4.1.3 The temperature effect 33
4.2 The Influence of DC stress 34
4.3 The Influence of Bending 34
4.4 The Influence of Back Light 35
4.4.1 The phenomenon of photon current 35
4.4.2 The photon current of SLS TFT with
grain boundary 36
Chapter 5 - Conclusion 37
References 38
Figures 46
Table 70

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