臺灣博碩士論文加值系統

傳統上，非晶矽薄膜電晶體主要應用於實現顯示面版，而不包括液晶螢幕的驅動電路。近年來，隨著system on glass (SOG)的概念提出，一些類比電路已經被整合到玻璃基板上。本篇論文，為了展示非晶矽薄膜電晶體製程在類比積體電路上的潛力，一個新穎的設計技巧被提出，其可減輕來自此半導體本身的限制。在第三章中，提出一個使用增益放大的技巧之新穎的運算放大器，因此低頻的增益可以有效的提升，並且幫助非晶矽薄膜電晶體的高等類比電路之實現。在第四章中，以第三章所提出的運算放大器為基礎，實現一個電阻串列數位類比轉換器於非晶矽薄膜電晶體製程中，同時此數位類比轉換器可更進一步應用於薄膜電晶體液晶螢幕中的資料線驅動電路。在第五章中，利用第三章中的完全差動放大器，開發了一個完全整合於玻璃基板上的觸控面版，其可以降低系統的成本，並使系統更精巧。

Conventionally, the amorphous-silicon (a-Si) thin-film-transistor (TFT) technology is primarily employed to realize the display panel excluding the driving circuits of LCDs. Recently, the concept of the system on glass (SOG) is introduced, and some analog circuits are integrated on the glass substrate. In this thesis, to demonstration the potential of the a-Si process for analog integrated circuits (ICs), novel design strategies are proposed to alleviate the intrinsic limitations imposed on this semiconductor. In Chapter 3, a novel operational amplifier (OPAMP) with a gain- enhancement technique is presented while the low-frequency gain can be effectively boosted, facilitating the realization of advanced analog circuits with a-Si TFTs. In Chapter 4, based on the OPAMP provided in Chapter 3, a prototype of the resistor-string digital-to-analog converter (DAC) is implemented in the a-Si technology while this DAC can be further applied in the source driver of the TFT-LCD. In Chapter 5, in cooperation of the fully differential amplifier in Chapter 3, a fully integrated touch panel on the glass substrate is developed, making the system inexpensive in cost and compact in layout area.

Acknowledgement i
Abstract iii
Table of Contents vii
List of Figures xi
List of Tables xv

Chapter 1 Introduction 1
1.1 Introduction to TFT-LCD 1
1.1.1 Brief History of TFT-LCDs 1
1.1.2 TFT-LCD System 3
1.1.3 Concept of System on Glass (SOG) 5
1.2 Motivation of this Thesis 6
1.2.1 Recent Development of Analog Circuits in a-Si Technologies 6
1.2.2 Applications of Analog Circuits in a-Si Technologies 6
1.3 Organization of this Thesis 7

Chapter 2 Review of a-Si Technologies 9
2.1 Introduction to a-Si Technologies 9
2.2 Thin Film Transistors in a-Si Technologies 11
2.2.1 DC Characteristics 11
2.2.2 AC Characteristics 13
2.2.3 Measurement of Testkeys 15
2.3 Passive Devices in a-Si Technologies 19
2.3.1 Resistance 19
2.3.2 Capacitance 20

Chapter 3 The Proposed OPAMP in a-Si Technologies 23
3.1 Design Challenges of OPAMP in a-Si Technologies 24
3.2 The Proposed Topology of OPAMP 27
3.2.1 A Gain-Enhancement Technique 27
3.2.2 The Differential-to-Single-Ended Converter 35
3.3 Circuit Implementation 38
3.4 Experimental Results 39
3.5 Summary 42

Chapter 4 The Proposed DAC in a-Si Technologies 45
4.1 Design Challenges of DAC in a-Si Technologies 45
4.2 The Proposed Topology of DAC 48
4.2.1 Resistor String and Switching Matrix 48
4.2.2 Unity-Gain Buffer 49
4.3 Circuit Implementation 49
4.4 Experimental Results 51
4.5 Summary 53

Chapter 5 The Prototype of Touch Panel in a-Si Technologies 55
5.1 Recent Development of Touch Panel 55
5.2 The Proposed Topology of Touch Panel 56
5.2.1 Photo Sensor 57
5.2.2 Comparator 59
5.2.3 Controlled Logic Circuits 63
5.3 Circuit Implementation 64
5.4 Simulated Results 64
5.5 Summary 65

Chapter 6 Conclusion 69

Bibliography 73

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