臺灣博碩士論文加值系統

本實驗企劃透過建構光電藝術實驗室，蒐集光電藝術的相關資料，並進一步了解軟性顯示器的應用，此計畫針對師範大學的教學卓越計畫執行為期一年的實驗，並於98年全國大專院校運動會中，聘請Onedotzero團隊，設計巨像投影於師大分部的教學大樓牆面。
在設計和製造全彩電子紙中，我們針對電子紙的QVGA(320xRGBx240)全彩的1T1C架構，並計算薄膜電晶體畫素與儲存電容的最佳化配置，完成IC、面板、電路板及訊號端的連結。我們還研究了有關軟性顯示器的驅動電晶體特性。經由實驗我們更充分了解軟性顯示器中驅動電晶體的特性，在量測結果方面，塑膠基板的top gate微晶矽薄膜電晶體(W/L =80μm/24μm)的遷移率、次臨界擺幅及臨界電壓分別為0.81 cm2/Vs、0.69 V/dec及 -1.99 V，並計算薄膜電晶體的缺陷狀態密度，討論機械彎曲與缺陷形成的關係。而用於軟性顯示器上的電流驅動元件，如有機發光二極體，需要驅動電晶體維持穩定的輸出電流與臨界電壓。因此，我們進行了各種薄膜電晶體（玻璃基板的top/bottom gate 非晶矽薄膜電晶體、塑膠基板的bottom gate非晶矽/微晶矽薄膜電晶體、玻璃/塑膠基板的 top gate微晶矽薄膜電晶體）的機械和電的可靠度研究。此外，未來的軟性顯示器中，在相近的可靠度之下，微晶矽薄膜電晶體會比多晶矽薄膜晶體更能達成降低成本的需求。

This work investigated optoelectronic art and demonstrated flexible displays through a laboratory. Part of optoelectronic art, great image projection was mainly supported by Teaching Excellence Project in National Taiwan Normal University (NTNU). With the assist of Onedotzero, the project also displayed an image projection on the wall of Lecture and Research Building in the NTNU’s branch.
Part of flexible display, in the design and fabrication of full-color e-paper, we focused on QVGA (320xRGBx240) full-color and 1T1C structure for electrophorectic display (EPD) and optimum ratio of thin film transistor (TFT) pixel to storage capacitor (Cst). The several works had been down, including IC banding, linking of panel, printed circuit board (PCB) and input signal end. We also studied more about the characteristics of driving transistors with flexible displays. The results of measurement, the effective mobility (μ), subthreshold swing (S.S.) and threshold voltage (Vth) of top gate microcrystalline silicon (μc-Si:H) TFTs on plastic substrate (W/L=80μm/24μm)are ~ 0.81 cm2/Vs, ~ 0.69 V/dec and -1.99 V, respectively. Then, we calculated density-of-states (DOS) and discussed the relationship between mechanical bending and traps formation. The current driving diode, such as organic light emitting diode (OLED), has the requirements of driving TFT with stable current output and Vth for flexible display. Therefore, the mechanical and electrical reliability of all kinds TFTs (top/bottom gate a-Si:H TFT on glass, bottom gate a-Si:H/μc-Si:H TFT on PI, top gate μc-Si:H TFT on glass/PI) have been studied. Besides, the advantage of μc-Si:H TFT has cost down as compare with poly-Si TFT with similar reliability for future flexible display.

Publication I
Acknowledge II
Chinese Abstract III
English Abstract IV
Contents VI
List of Figures VIII
List of Tables XIII

Chapter 1 Optoelectronic Art with Flexible Display and
Image Projection 1
1.1 Introduction 1
1.2 Optoelectronic Art Workshop 2

Chapter 2 The Backplane Array Design and Process for
Flexible Electrophoretic Display Applications 5
2.1 Introduction 5
2.2 Panel Design for EPD 6
2.3 Experimental 10
2.4 Summary 18

Chapter 3 Top Gate Microcrystalline Silicon and
Amorphous Silicon TFTs on Glass 19
3.1 Introduction 19
3.2 Top Gate μc-Si:H / a-Si:H TFTs Fabrication 20
3.3 Density-of-State Extraction 21
3.4 Measurements of Electrical Characteristics 22
3.5 Electrical Characteristics of TFTs 23
3.5.1 Top Gate μc-Si:H TFTs on Glass 23
3.5.2 Top Gate a-Si:H TFTs on Glass 27
3.6 Conclusion 32

Chapter 4 μc-Si:H TFTs on PI with High Mechanical and
Electrical Reliability for Flexible Display 33
4.1 Introduction 33
4.2 TFTs on PI Substrate Fabrication 34
4.2.1 Top Gate μc-Si:H TFTs 34
4.2.2 Bottom Gate μc-Si:H TFTs 35
4.3 Substrate Characteristics 37
4.4 Strain of TFTs 39
4.4.1 Bending Simulation 39
4.4.2 TFTs of Mechanical Bending 42
4.5 Top / Bottom Gate μc-Si:H TFT on PI Stability 47
4.5.1 Constant Current Stress 47
4.5.2 Positive Bias Temperature Instability 50
4.6 Summary 53

Chapter 5 Conclusion and Future Works 54
5.1 Conclusions 54
5.2 Future Works 57
References 59

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