為滿足高解析度、更大尺寸的液晶( LCD) 和有源有機發光二極體( AMOLED) 等新型顯示技術發展的需要，近幾年氧化物半導體開始被人們重視，氧化物半導體材料因其載子遷移率高、製備溫度低、對可見光透明和成本低等優勢，被認為是最適合驅動有機發光二極體的薄膜電晶體(TFT)的半導體主動層材料之一。目前氧化物TFT已成功地應用在平面顯示的驅動背板上。然而，氧化物半導體要大量應用於顯示器工業上仍有許多可靠度的問題須克服與釐清，例如：實際畫素陣列電路中操作時容易因為操作電壓以及電流而有各種劣化現象；以及未來應用於可撓式顯示器時，各種彎曲機械應力或是多次數彎摺下，勢必導致電晶體在電性與可靠度帶來影響。因此本論文分成兩大主題進行研究探討，主題一為電應力可靠度研究，即熱載子效應；主題二為機械彎應力(包括重複多次數)對於元件所造成之劣化情況。
本論文針對主題一分成兩個部分來探討，第一部分為氧化銦鎵鋅(InGaZnO)薄膜電晶體之基本特性探討，透過變溫量測發現元件電性隨著溫度越高而導致起始電壓VT及電流上升的趨勢，並且透過阿瑞尼茲方程式萃取出元件活化能，發現活化能與閘極偏壓呈現正相關，也藉由電流-電壓曲線計算出載子濃度對載子遷移率作圖，其趨勢皆符合percolation模型；而我們在其中一個研究發現元件在高溫時，除了起始電壓向左飄移外還額外產生異常寄生電流，我們透過元件於高溫閘極負偏壓下進行元件不同通道寬度之電應力測試，以及電場模擬確認於主動層與保護層之側面利於電洞注入，因此電洞促使側向通道產生了寄生電流導致這異常現象。
主題一第二部分，熱載子效應在具有蝕刻終止層的接觸窗口型元件會造成電子注入到汲極延伸電極下方的通道蝕刻終止層中，這樣的電子注入情形造成閘極-源極電容曲線有兩階段抬升現象，而由汲極延伸電極長度對閘極-源極電容曲線第一階段高度的影響，我們可以知道電容曲線的兩階段抬升是受汲極電極主導。藉由電容-電壓曲線換算出注入位置與範圍的手法，得到這些注入的電子會被侷限在延伸電極的位置，前述的劣化機制模型得到了驗證。本論文更深入研究熱載子效應在不同元件結構下的劣化情形，結構分為延伸電極於通道寬度方向大於/等於主動層以及不對稱幾何形狀電極(擁有I形與U形電極之元件)，其分別定義為SD Large、SD Normal以及不對稱UI結構，由先前實驗團隊建立之基礎，以上元件結構在熱載子效應下，其電性劣化原因皆為電子注入於靠近汲極端之延伸電極所導致，但於SD Normal以及UI結構中U為汲極操作時，其元件於熱載子效應下，實驗發現除了起始電壓飄移外，並額外有寄生通道的產生，此劣化現象與電場有關，藉由電場模擬結果，驗證了電極於圓角處因為電場較弱，弱電場導致較少電子注入於其延伸電極下方，導致整體產生具有寄生電流之劣化情形。
接著本論文主題二為可撓式薄膜電晶體(flexible TFT)之電性與可靠度研究，可撓式薄膜電晶體研究是現今最受矚目之技術，擁有輕薄、可撓曲、容易隨身攜帶等特性。此主題分成兩個部分作討論，第一部分為可撓式氧化銦鎵鋅薄膜電晶體於固定張應力及壓應力情況下，研究應力軸垂直通道電流方向對於不同曲率半徑下對元件電性上的影響，並配合載子遷移率和次臨界擺幅之萃取以及電容-電壓量測結果，分析使否有缺陷產生。並研究不同撓曲程度對元件於照光閘極負偏壓下之可靠度問題。實驗結果發現不論是張應力或壓應力對氧化銦鎵鋅薄膜電晶體皆導致元件起始電壓往負方向漂移，隨著應力越大飄移量越多，並且元件有額外缺陷產生導致載子遷移率與次臨界擺幅皆變差，而在電應力可靠度上，也顯示隨著元件遭受更多應力，其可靠度越差。以上的劣化我們認為主要原因為應力造成InGaZnO產生額外氧空缺所致，透過元件純照射紫外(UV)光之劣化情形，更加驗證我們提出的模型。
主題二最後一部分，探討重覆多次數彎曲應力對氧化銦鎵鋅薄膜電晶體之影響，觀察元件於重覆一千次彎曲一直到五萬次後元件之劣化情形，以及研究對稱結構與不對稱UI結構元件對於重覆多次數彎曲應力下，是否產生不一樣之劣化結果，而此實驗之彎曲應力，又分為應力軸平行或垂直於通道電流方向兩種情況。實驗結果再一次指出應力使得元件產生額外氧空缺，導致隨著元件彎曲次數變多，起始電壓向左飄移之情形越嚴重。而在不同元件結構對於應力之影響，實驗發現在應力軸垂軸於通道電流方向時，只有UI結構之元件於重覆次數彎曲應力後，會有不對稱之電性劣化，其餘情況於多次數彎曲應力後，皆顯示對稱之電性劣化。藉由應力模擬結果，釐清了此不對稱劣化是源自結構造成應力分佈不均，進而導致氧化銦鎵鋅主動層內部氧空缺不對稱分佈所致。而其餘情況之應力模擬結果，顯示整體主動層應力分佈均勻，與實驗結果吻合。

In order to meet the requirements of novel display technologies such as high-resolution large-screen LCD and AMOLED. Oxide semiconductor thin film transistors (TFTs) have attracted much attention recently since they possess many advantageous properties of high mobility, low-temperature processing, good electrical uniformity, visible-light transparency, and low cost that are beneficial in the development of displays. They are regarded as one of most suitable active materials of TFTs for driving organic light-emitting diodes. Currently oxide TFTs have been successfully applied to the backplanes of the flat-panel displays. However, operation voltage and/or current can lead to device degradation in practical applications. Flexible oxide TFTs suffer from an additional issue, that of their reliability under mechanical stress. Therefore, two main topic are researched: (i) the effects of hot-carriers and (ii) the effect of mechanical strain in InGaZnO thin-film transistors are investigated in this work.
In the first topic of this dissertation, behaviors of carrier transport in amorphous indium-gallium-zinc oxide (a-InGaZnO) thin film transistors are investigated. It is found that the electron mobility is higher at elevated temperatures, which is contrary to that in crystalline Si devices. Drain current enhancement with regard to temperature at corresponding gate voltage follows the Arrhenius equation. This implies that carrier transport is limited by the potential barrier heights induced by trap states within InGaZnO, and therefore current conduction is heat-activated to overcome those barriers. Furthermore, the relationship between carrier mobility and carrier concentration is also investigated, with the carrier mobility monotonically increasing with carrier concentration. Such behavior can be ascribed to a lowered effective barrier above the conduction band when the Fermi-level rises. The abnormal hump phenomenon emerging in the transfer characteristics of amorphous InGaZnO thin film transistors under negative bias stress (NBS) along with a negative shift of threshold voltage was also investigated. The magnitude of the parasitic on-state current increases with the measured temperature, indicating that high temperature can induce more charge injection. Furthermore, we consider that the parasitic channel originates from the hole trapping near the InGaZnO edges by simulation results. The greater gate voltage leads to the faster hole injection and the more negative shift.
In the second section of topic one, current-voltage as well as capacitance-voltage measurements are utilized to analyze the electrical properties of via-contact type a-InGaZnO TFTs with an etch stop layer (ESL) after hot-carrier stress. Unlike what is commonly observed in the devices without ESL, hot-carrier stress-induced electron-trapping in the ESL device is found to be influenced by the pattern of the redundant drain electrode. Furthermore, to gain a deeper insight into hot carrier effect on different device structure, via-contact structure TFTs with three different types of source/drain distribution were also analyzed after hot-carrier stress. We discovered a phenomenon of a parasitic transistor caused by asymmetrical degradation of electrode geometry. A simulation of electric field perfectly explains the characteristic of degradation in different devices.
The second topic characterized the effect of mechanical strain in flexible a-InGaZnO thin-film transistors. Drain current–gate voltage (ID–VG) as well as capacitance-voltage (C-V) transfer curves are measured to analyze the degradation behavior. The ID-VG characteristic exhibits an obvious negative shift under mechanical strain regardless of tension or compression state. In addition, the C-V characteristic curves show a leftward shift with extra distortion or stretching out under mechanical strain. This indicates that the InGaZnO generates additional defects under this mechanical strain, a phenomenon which can be attributed to the generation of mechanical strain-induced oxygen vacancies on the flexible a-InGaZnO TFTs.
Finally, in the second section investigates repeated uniaxial mechanical stress-induced degradation behavior in flexible a-InGaZnO thin-film transistors (TFTs) of different geometric structures. Two types of via-contact structure TFTs are investigated: symmetrical and UI structures. After repeated mechanical stress, I-V curves for the symmetrical structure show a significant negative threshold voltage (VT) shift, due to mechanical stress-induced oxygen vacancy generation. However, degradation in the UI structure TFTs after stress is a negative VT shift along with the parasitic transistor characteristic under forward-operation mode, with this hump not evident under reverse-operation mode. This asymmetrical degradation is clarified by mechanical strain simulation of the UI TFTs.

Contents

摘要 iii
Abstract vi
Figure Captions xii
Chapter 1 Introduction 1
1.1 Overview of Active-Matrix Flat Panel Displays 1
1.2 Overview of Amorphous Oxide Semiconductors 3
1.3 Motivation 6
1.4 References 12
Chapter 2 Parameter Extraction Methodology 14
2.1 The VT extraction method 14
2.2 The subthreshold swing extraction method 15
2.3 The carrier mobility extraction method 16
Chapter 3 Investigation of Carrier Transport Behavior in a-InGaZnO Thin Film Transistors 19
3.1 Introduction 19
3.2 Experiment 20
3.3 Results and Discussion 21
3.4 Summary 27
3.5 References 38
Chapter 4 Investigation of Hot-Carrier Effect in Via-Contact Type a-InGaZnO Thin-Film Transistors with an Etch Stop Layer 42
4.1 Introduction 42
4.3 Results and Discussion 45
a. Hot-Carrier Effect-Induced Degradation Behaviors 45
b. Effect of Device Electrode Geometry on Performance after Hot-Carrier Stress. 49
4.4 Summary 53
4.5 References 67
Chapter 5 The effect of mechanical strain-induced defect generation on the performance of flexible a-InGaZnO TFT 70
5.1 Introduction 70
5.2 Experiment 71
5.3 Results and Discussion 72
5.4 Summary 79
5.5 References 93
Chapter 6 Impact of repeated uniaxial mechanical strain on flexible a-InGaZnO thin film transistors with symmetric and asymmetric structures 96
6.1 Introduction 96
6.3 Results and Discussion 99
6.4 Summary 105
6.5 References 117
Chapter 7 Conclusion 120
Vita 簡 歷 129

Chapter 1
[1] Kamiya, Toshio, Kenji Nomura, and Hideo Hosono. "Present status of amorphous In–Ga–Zn–O thin-film transistors." Science and Technology of Advanced Materials 11.4 (2010): 044305.
[2] Hosono, Hideo. "Ionic amorphous oxide semiconductors: Material design, carrier transport, and device application." Journal of Non-Crystalline Solids 352.9 (2006): 851-858.
[3] Kamiya, Toshio, and Hideo Hosono. "Material characteristics and applications of transparent amorphous oxide semiconductors." NPG Asia Materials 2.1 (2010): 15-22.
[4] Nomura, Kenji, et al. "Room-temperature fabrication of transparent flexible thin-film transistors using amorphous oxide semiconductors." Nature 432.7016 (2004): 488-492.
[5] Fortunato, Elvira MC, et al. "Fully Transparent ZnO Thin‐Film Transistor Produced at Room Temperature." Advanced Materials 17.5 (2005): 590-594.
[6] Lee, Ho‐Nyun, et al. "68.2: 3.5 Inch QCIF+ AM‐OLED Panel Based on Oxide TFT Backplane." SID Symposium Digest of Technical Papers. Vol. 38. No. 1. Blackwell Publishing Ltd, 2007.
[7] Liu, Po-Tsun, Yi-Teh Chou, and Li-Feng Teng. "Environment-dependent metastability of passivation-free indium zinc oxide thin film transistor after gate bias stress." Applied Physics Letters 95.23 (2009): 233504.
[8] Chung, Wan-Fang, et al. "Environment-dependent thermal instability of sol-gel derived amorphous indium-gallium-zinc-oxide thin film transistors." Applied Physics Letters 98.15 (2011): 152109.
[9] Chen, Te-Chih, et al. "Light-induced instability of an InGaZnO thin film transistor with and without SiO x passivation layer formed by plasma-enhanced-chemical-vapor-deposition." Applied Physics Letters 97.19 (2010): 192103.
[10] Görrn, P., et al. "The influence of visible light on transparent zinc tin oxide thin film transistors." Applied Physics Letters 91.19 (2007): 193504.
Chapter 3
[1] Chang, Ting-Chang, et al. "Developments in nanocrystal memory." Materials today 14.12 (2011): 608-615.
[2] Syu, Yong-En, et al. "Redox Reaction Switching Mechanism in RRAM Device With $hbox {Pt/CoSiO} _ {X}hbox {/}hbox {TiN} $ Structure." IEEE Electron Device Letters 32.4 (2011): 545-547.
[3] Nomura, Kenji, et al. "Room-temperature fabrication of transparent flexible thin-film transistors using amorphous oxide semiconductors." Nature 432.7016 (2004): 488-492.
[4] Lee, Ho‐Nyun, et al. "68.2: 3.5 Inch QCIF+ AM‐OLED Panel Based on Oxide TFT Backplane." SID Symposium Digest of Technical Papers. Vol. 38. No. 1. Blackwell Publishing Ltd, 2007.
[5] Görrn, P., et al. "The influence of visible light on transparent zinc tin oxide thin film transistors." Applied Physics Letters 91.19 (2007): 193504.
[6] Fortunato, Elvira MC, et al. "Fully Transparent ZnO Thin‐Film Transistor Produced at Room Temperature." Advanced Materials 17.5 (2005): 590-594.
[7] Chen, Te-Chih, et al. "Light-induced instability of an InGaZnO thin film transistor with and without SiO x passivation layer formed by plasma-enhanced-chemical-vapor-deposition." Applied Physics Letters 97.19 (2010): 192103.
[8] Liu, Po-Tsun, Yi-Teh Chou, and Li-Feng Teng. "Environment-dependent metastability of passivation-free indium zinc oxide thin film transistor after gate bias stress." Applied Physics Letters 95.23 (2009): 233504.
[9] Chung, Wan-Fang, et al. "Environment-dependent thermal instability of sol-gel derived amorphous indium-gallium-zinc-oxide thin film transistors." Applied Physics Letters 98.15 (2011): 152109..
[10] Chen, Te-Chih, et al. "Investigating the degradation behavior caused by charge trapping effect under DC and AC gate-bias stress for InGaZnO thin film transistor." Applied Physics Letters 99.2 (2011): 022104.
[11] Valletta, Antonio, et al. "Self-heating effects in polycrystalline silicon thin film transistors." Applied physics letters 89.9 (2006): 093509.
[12] Fujii, Mami, et al. "Thermal analysis of degradation in Ga2O3–In2O3–ZnO thin-film transistors." Japanese Journal of Applied Physics 47.8R (2008): 6236.
[13] Hosono, Hideo. "Ionic amorphous oxide semiconductors: Material design, carrier transport, and device application." Journal of Non-Crystalline Solids 352.9 (2006): 851-858.
[14] Kamiya, Toshio, and Hideo Hosono. "Material characteristics and applications of transparent amorphous oxide semiconductors." NPG Asia Materials 2.1 (2010): 15-22.
[15] Kamiya, Toshio, Kenji Nomura, and Hideo Hosono. "Present status of amorphous In–Ga–Zn–O thin-film transistors." Science and Technology of Advanced Materials 11.4 (2010): 044305.
[16] Yang, Jianwen, et al. "The stability of tin silicon oxide thin-film transistors with different annealing temperatures." EPL (Europhysics Letters) 115.2 (2016): 28006.
[17] Lee, Kwang-Hee, et al. "The effect of moisture on the photon-enhanced negative bias thermal instability in Ga–In–Zn–O thin film transistors." Applied physics letters 95.23 (2009): 232106.
[18] Yang, Shinhyuk, et al. "Improvement in the photon-induced bias stability of Al–Sn–Zn–In–O thin film transistors by adopting AlO x passivation layer." Applied Physics Letters 96.21 (2010): 213511.
[19] Gwang Um, Jae, et al. "Increase of interface and bulk density of states in amorphous-indium-gallium-zinc-oxide thin-film transistors with negative-bias-under-illumination-stress time." Applied Physics Letters 101.11 (2012): 113504.
[20] Kim, Jang Hyun, et al. "Investigation on the characteristics of stress-induced hump in amorphous oxide thin film transistors." Applied Physics Letters 99.4 (2011): 043502.
[21] Huang, Ching-Fang, et al. "Stress-induced hump effects of p-channel polycrystalline silicon thin-film transistors." IEEE Electron Device Letters 29.12 (2008): 1332-1335.
Chapter 4
[1] Fortunato, Elvira MC, et al. "Fully Transparent ZnO Thin‐Film Transistor Produced at Room Temperature." Advanced Materials 17.5 (2005): 590-594.
[2] Nomura, Kenji, et al. "Room-temperature fabrication of transparent flexible thin-film transistors using amorphous oxide semiconductors." Nature 432.7016 (2004): 488-492.
[3] Yabuta, Hisato, et al. "High-mobility thin-film transistor with amorphous In Ga Zn O 4 channel fabricated by room temperature rf-magnetron sputtering." Applied physics letters 89.11 (2006): 112123.
[4] Cai, Wensi, et al. "Transparent Thin-Film Transistors Based on Sputtered Electric Double Layer." Materials 10.4 (2017): 429.
[5] Lee, Jeong-Min, et al. "Bias-stress-induced stretched-exponential time dependence of threshold voltage shift in InGaZnO thin film transistors." Applied Physics Letters 93.9 (2008): 093504.
[6] Liu, Po-Tsun, Yi-Teh Chou, and Li-Feng Teng. "Environment-dependent metastability of passivation-free indium zinc oxide thin film transistor after gate bias stress." Applied Physics Letters 95.23 (2009): 233504.
[7] Domen, Kay, et al. "Positive gate bias instability induced by diffusion of neutral hydrogen in amorphous In-Ga–Zn-O thin-film transistor." IEEE Electron Device Letters 35.8 (2014): 832-834.
[8] Chen, Te-Chih, et al. "Light-induced instability of an InGaZnO thin film transistor with and without SiO x passivation layer formed by plasma-enhanced-chemical-vapor-deposition." Applied Physics Letters 97.19 (2010): 192103.
[9] Hsieh, Tien-Yu, et al. "Investigating the drain-bias-induced degradation behavior under light illumination for InGaZnO thin-film transistors." IEEE Electron device letters 33.7 (2012): 1000-1002.
[10] Furuta, Mamoru, et al. "Analysis of hump characteristics in thin-film transistors with ZnO channels deposited by sputtering at various oxygen partial pressures." IEEE Electron Device Letters 31.11 (2010): 1257-1259.
[11] Urakawa, Satoshi, et al. "Thermal analysis of amorphous oxide thin-film transistor degraded by combination of joule heating and hot carrier effect." Applied Physics Letters 102.5 (2013): 053506.
[12] Mativenga, Mallory, Sejin Hong, and Jin Jang. "High current stress effects in amorphous-InGaZnO4 thin-film transistors." Applied Physics Letters 102.2 (2013): 023503.
[13] Cho, In-Tak, et al. "Charge trapping and detrapping characteristics in amorphous InGaZnO TFTs under static and dynamic stresses." Semiconductor Science and Technology 24.1 (2008): 015013.
[14] Shin, Jae-Heon, et al. "Light effects on the bias stability of transparent ZnO thin film transistors." Etri Journal 31.1 (2009): 62-64.
[15] Chen, Te-Chih, et al. "Investigating the degradation behavior caused by charge trapping effect under DC and AC gate-bias stress for InGaZnO thin film transistor." Applied Physics Letters 99.2 (2011): 022104.
[16] Libsch, F. R., and J. Kanicki. "Bias‐stress‐induced stretched‐exponential time dependence of charge injection and trapping in amorphous thin‐film transistors." Applied Physics Letters 62.11 (1993): 1286-1288.
[17] Hsieh, Tien-Yu, et al. "Hot-carrier effect on amorphous In-Ga-Zn-O thin-film transistors with a via-contact structure." IEEE Electron Device Letters 34.5 (2013): 638-640.
Chapter 5
[1] Nishide, Hiroyuki, and Kenichi Oyaizu. "Toward flexible batteries." Science 319.5864 (2008): 737-738.
[2] Koo, Min, et al. "Bendable inorganic thin-film battery for fully flexible electronic systems." Nano letters 12.9 (2012): 4810-4816.
[3] Mentley, David E. "State of flat-panel display technology and future trends." Proceedings of the IEEE 90.4 (2002): 453-459.
[4] Nomura, Kenji, et al. "Room-temperature fabrication of transparent flexible thin-film transistors using amorphous oxide semiconductors." Nature 432.7016 (2004): 488-492.
[5] Hayashi, Ryo, et al. "Circuits using uniform TFTs based on amorphous In‐Ga‐Zn‐O." Journal of the Society for Information Display 15.11 (2007): 915-921.
[6] Fortunato, Elvira MC, et al. "Fully Transparent ZnO Thin‐Film Transistor Produced at Room Temperature." Advanced Materials 17.5 (2005): 590-594.
[7] Lee, Ho‐Nyun, et al. "68.2: 3.5 Inch QCIF+ AM‐OLED Panel Based on Oxide TFT Backplane." SID Symposium Digest of Technical Papers. Vol. 38. No. 1. Blackwell Publishing Ltd, 2007.
[8] Chen, Te-Chih, et al. "Light-induced instability of an InGaZnO thin film transistor with and without SiO x passivation layer formed by plasma-enhanced-chemical-vapor-deposition." Applied Physics Letters 97.19 (2010): 192103.
[9] Chen, Yu-Chun, et al. "Bias-induced oxygen adsorption in zinc tin oxide thin film transistors under dynamic stress." Applied Physics Letters 96.26 (2010): 262104.
[10] Hsieh, Tien-Yu, et al. "Investigating the drain-bias-induced degradation behavior under light illumination for InGaZnO thin-film transistors." IEEE Electron device letters 33.7 (2012): 1000-1002.
[11] Hoffman, R. L., Benjamin J. Norris, and J. F. Wager. "ZnO-based transparent thin-film transistors." Applied Physics Letters 82.5 (2003): 733-735.
[12] Choi, Jun Hyuk, et al. "Transfer characteristics and bias-stress stability of amorphous indium zinc oxide thin-film transistors." Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena 27.2 (2009): 622-625.
[13] Lin, Chang-Yu, et al. "Effects of mechanical strains on the characteristics of top-gate staggered a-InGaZnO thin-film transistors fabricated on polyimide-based nanocomposite substrates." IEEE Transactions on Electron Devices 59.7 (2012): 1956-1962.
[14] Munzenrieder, Niko, Kunigunde H. Cherenack, and Gerhard Troster. "The effects of mechanical bending and illumination on the performance of flexible InGaZnO TFTs." IEEE Transactions on Electron Devices 58.7 (2011): 2041-2048.
[15] Eun, K. T., et al. "Mechanical flexibility of zinc oxide thin-film transistors prepared by transfer printing method." Modern Physics Letters B 26.12 (2012): 1250077.
[16] Gleskova, Helena, S. Wagner, and Z. Suo. "a-Si: H thin film transistors after very high strain." Journal of Non-Crystalline Solids 266 (2000): 1320-1324.
[17] Takechi, Kazushige, et al. "Comparison of ultraviolet photo-field effects between hydrogenated amorphous silicon and amorphous InGaZnO4 thin-film transistors." Japanese Journal of Applied Physics 48.1R (2009): 010203.
[18] Oh, Himchan, et al. "Photon-accelerated negative bias instability involving subgap states creation in amorphous In–Ga–Zn–O thin film transistor." Applied physics letters 97.18 (2010): 183502.
Chapter 6
[1] Chang, Ting-Chang, et al. "Developments in nanocrystal memory." Materials today 14.12 (2011): 608-615.
[2] Syu, Yong-En, et al. "Redox Reaction Switching Mechanism in RRAM Device With $hbox {Pt/CoSiO} _ {X}hbox {/}hbox {TiN} $ Structure." IEEE Electron Device Letters 32.4 (2011): 545-547.
[3] Chen, Min-Chen, et al. "Influence of electrode material on the resistive memory switching property of indium gallium zinc oxide thin films." Applied Physics Letters 96.26 (2010): 262110.
[4] Nishide, Hiroyuki, and Kenichi Oyaizu. "Toward flexible batteries." Science 319.5864 (2008): 737-738.
[5] Koo, Min, et al. "Bendable inorganic thin-film battery for fully flexible electronic systems." Nano letters 12.9 (2012): 4810-4816.
[6] Mentley, David E. "State of flat-panel display technology and future trends." Proceedings of the IEEE 90.4 (2002): 453-459.
[7] Nomura, Kenji, et al. "Room-temperature fabrication of transparent flexible thin-film transistors using amorphous oxide semiconductors." Nature 432.7016 (2004): 488-492.
[8] Hayashi, Ryo, et al. "Circuits using uniform TFTs based on amorphous In‐Ga‐Zn‐O." Journal of the Society for Information Display 15.11 (2007): 915-921.
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