臺灣博碩士論文加值系統

主動矩陣有機發光二極體(Active Matrix Organic Light-Emitting Display)必須採用薄膜電晶體(Thin-Film Transistor)作為驅動與開關元件，而半導體製程中常因環境與人為因素造成元件特性穩定性不足或者因長時間的使用造成元件衰減，如薄膜電晶體元件的臨界電壓(Threshold Voltage)，當畫素電路中薄膜電晶體特性產生漂移，整體面板的亮度均勻性就受到相當大的影響。此外有機發光二極體本身的材料變異也會直接影響到面板的顯像品質。
本論文提出兩個新式畫素補償電路，用以提升主動矩陣有機發光二極體的顯示品質並且驗證先前實驗室研究發表的畫素電路架構。第一個提出的電路是利用3T1C的架構來補償薄膜電晶體臨界電壓值的變異。第二個電路則改善前一電路的缺點並且保持3T1C的架構以及簡單訊號線的特性來補償薄膜電晶體。這兩個電路不僅可以大幅提升顯示的均勻性，亦可以提高面板開口率使亮度上升，具有相當的應用價值。最後實際量測實驗室先前的5T1C畫素電路架構，同時補償薄膜電晶體與有機發光二極體的材料變異，實驗結果驗證不僅提昇面板均勻性並且增加有機發光二極體的顯像壽命。

An active matrix organic light emitting diode (AMOLED) uses thin film transistor (TFT) as driving and switching component. However, a non-negligible VTH variation of the driving TFT due to process variation or prolonged operation directly influences the quality of the AMOLED display.
This thesis proposes two novel pixel circuits and experimentally verifies the results of previous research. The first proposed 3T1C circuit is associated with a novel driving scheme to compensate for the threshold voltage shift in driving TFT with the simplest control signals. The second proposed 3T1C circuit operates in the triode region and improves upon the high-power consumption of the first circuit. Moreover, the second circuit keeps the simplest control signals and the fewer TFTs structure. The proposed circuits are associated with entirely new driving schemes for an AMOLED pixel circuit and will contribute markedly to AMOLED applications in the future.
The previously proposed 5T1C circuit is fabricated and its performance is measured in this thesis. The experimental results reveal that the circuit can improve the uniformity of the display and extended the lifetime of the AMOLED display.

Chinese Abstract i
English Abstract ii
Acknowledgements iii
Contents iv
Table Captions vi
Figure Captions vii
Chapter 1 Introduction
1.1 Background 1
1.2 Motivation 6
1.3 Thesis organization 10
Chapter 2 A Novel Voltage Driving Method Using 3-TFT Pixel Circuit for AMOLED
2.1 Introduction 11
2.2 Proposed Pixel Circuit Operation 12
2.3 Stability Analysis 13
2.4 Simulation Results 15
2.3 Conclusions 17
Chapter 3 Novel Pixel Circuit Based Simple and Effective Driving Schemes for AMOLED
3.1 Introduction 21
3.2 Proposed Pixel Circuit Operation 22
3.3 Simulation Results 24
3.3 Conclusions 26
Chapter 4 A Novel Voltage-Feedback Pixel Circuit for AMOLED Displays
4.1 Introduction 30
4.2 Proposed Pixel Circuit Operation 33
4.3 Simulation and Experimental Results 36
4.4 Conclusions 38

Chapter 5 Conclusions 44
References 45
Vita 50
Publication Lists 51

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