本論文研究一般使用於液晶顯示器(LCD)之非晶矽薄膜電晶體(a-Si:H TFT)的電性表現，並研究新興的非晶態銦鎵鋅氧化物薄膜電晶體(a-IGZO TFT)之電性特徵。為因應現代可攜式顯示器與大面積化顯示器之應用，傳統薄膜電晶體液晶顯示器(TFT-LCD)技術，面臨許多的挑戰與問題。一般而言，軟性顯示器必須具備一定程度的可彎曲能力；然而，彎曲顯示器會施加機械應力於電路上，並且影響元件的特性表現。因此，我們研究製作於金屬基板上的a-Si:H TFT，在施加單一方向之彎曲下，於不同溫度下的電性表現。實驗結果顯示，元件的開啟飽和電流(on-state current)與臨限電壓(threshold voltage)，在外彎曲的狀態下會劣化變差。這是由於施加外彎曲於元件上會導致帶尾能態(band tail states)增加，以致於影響不同溫度下的傳輸機制。另外，在實際的運作方面，我們研究a-Si:H TFT在未彎曲與彎曲狀態下，經過AC/DC stress後，於不同溫度下的電性表現。由此我們發現到，高溫與機械應力在AC stress中扮演很重要的角色。我們亦發現在AC stress下，偏壓上升及下降的累積時間與臨限電壓的改變具有相依性。
由於a-Si:H是一種光感物質，高強度的背光照射將會使得a-Si:H TFT的性能下降。因此我們研究a-Si:H TFT在光照射時，於不同溫度下的光漏電流特性。實驗結果顯示，a-Si:H TFT在較低的溫度下呈現出較差的性能狀態。a-Si:H TFT在不同的溫度範圍下運作，其光漏電流會呈現不同的趨勢，是由於受間接複合率及寄生電阻(Rp)之影響。為了研究光漏電流，我們將a-Si:H TFTs置放於UV光下進行照射。結果發現經過UV光照射後，a-Si:H TFTs的光電流會降低。因此我們進一步討論，經過UV光照射後，使a-Si:H TFTs光電漏流降低(增加)的詳細機制。
近來，氧化物半導體薄膜電晶體(oxide-based semiconductor TFTs)，特別是a-IGZO TFT，被視為是一個有希望可運用於主動式陣列平面顯示器的候選者。但是，a-IGZO TFT仍存在重大的電性不穩定性與製造的問題。因此我們研究於製造a-IGZO TFT時，引入氫氣對減少主動層與絕緣層間之介面態的效果。實驗結果顯示，氫的引入使得a-IGZO TFT的電性表現有所改善。臨限電壓的改變在延滯現象的表現上由原來的4 V減少到2 V，這是由於氫的引入導致介面缺陷態的鈍化。最後，我們討論了週遭氣氛對a-IGZO TFT不穩定性的影響。當a-IGZO TFT置放於大氣下40天後，於bias stress下，傳輸特性會伴隨奇異的hump現象。這個hump現象被歸咎於是水分子的吸附所造成。同時，足夠的電場也被發現是造成此異常傳輸特性的必要條件之ㄧ。

In this dissertation, the electrical characteristics of generally used hydrogenated amorphous silicon (a-Si:H) TFTs in LCD and newly risen amorphous indium-gallium-zinc oxide (a-IGZO) TFTs were studied. For modern mobile display and large-size flat panel display application, the traditional thin-film transistor-liquid crystal display (TFT-LCD) technology confronts with a lot of challenges and problems. In general, flexible displays must exhibit some bending ability; however, bending applies mechanical strain to electronic circuits and affects device characteristics. Therefore, the electrical characteristics of a-Si:H TFTs fabricated on stainless steel foil substrates with uniaxial bending were investigated at different temperatures. Experimental results showed that the on-state current and threshold voltage degraded under outward bending. This is because outward bending will induce the increase of band tail states, affecting the transport mechanism at different temperatures. In addition, for practical operation, the electrical characteristics of a-Si:H TFTs under flat and bending situations after AC/DC stress at different temperatures were studied. It was found that high temperature and mechanical bending played important roles under AC stress. The dependence between the accumulated sum of bias rising and falling time and the threshold voltage shifts under AC stress was also observed.
Because a-Si:H is a photosensitive material, the high intensity backlight illumination will degrade the performance of a-Si:H TFTs. Thus, the photo-leakage current of a-Si:H TFTs under illumination was investigated at different temperatures. Experimental results showed that a-Si:H TFTs exhibited a pool performance at lower temperatures. The indirect recombination rate and the parasitic resistance (Rp) are responsible for the different photo-leakage-current trends of a-Si:H TFTs under varied temperature operations. To investigate the photo-leakage current, the a-Si:H TFTs were exposed to ultraviolet (UV) light irradiation. It was found that the photo current of a-Si:H TFTs was reduced after UV light irradiation. The detail mechanisms on reducing/increasing photo-leakage current by UV light irradiation were discussed.
Recently, the oxide-based semiconductor TFT, especially a-IGZO TFT, is considered as one of promising candidates for active matrix flat-panel display. However, the a-IGZO TFT exists significant electrical instability issue and manufacturing problems. As a consequence, we investigated the effect of hydrogen incorporation on a-IGZO TFTs to reduce interface states between active layer and insulator. Experimental results showed that the electrical characteristics of hydrogen-incorporated a-IGZO TFTs were improved. The threshold voltage shift (ΔVth) in hysteresis loop is suppressed from 4 V to 2 V due to the hydrogen-induced passivation of the interface trap states. Finally, we reported the effect of ambient environment on a-IGZO TFT instability. As a-IGZO TFTs were stored in atmosphere environment for 40 days, the transfer characteristics accompanying strange hump were observed during bias-stress. The hump phenomenon is attributed to the absorption of H2O molecule. Additionally, the sufficient electric field is also necessary to cause this anomalous transfer characteristic.

Chinese Abstract ---------------------------------------------------------------------------i
English Abstract --------------------------------------------------------------------------iv
Content --------------------------------------------------------------------------------------vii
Figure Captions ---------------------------------------------------------------------------xi
Chapter 1 - Introduction
1.1 General Background ---------------------------------------------------------------1
1.1.1 a-Si:H TFT used in flexible display ---------------------------------------3
1.1.2 Leakage current mechanisms of a-Si:H TFT ----------------------------5
1.1.3 Amorphous indium-gallium-zinc oxide (a-IGZO) TFT ----------------8
1.2 Organization of Dissertation ----------------------------------------------------10
Chapter 2 – Low-temperature Characteristics of a-Si:H Thin-film Transistor under Mechanical Strain
2.1 Introduction ------------------------------------------------------------------------18
2.2 Experimental Procedure ---------------------------------------------------------21
2.3 Results and Discussion -----------------------------------------------------------23
2.3.1 Transfer characteristics and Evaluation of density of state (DOS) ----23
2.3.2 Calculation by variable range hopping (VRH) --------------------------25
2.3.3 Thershold voltage behavior ------------------------------------------------27
2.3.4 Suggested mechanism -------------------------------------------------------28
2.4 Conclusions -------------------------------------------------------------------------29
Chapter 3 - Influence of Mechanical Bending on the Threshold Voltage Instability of a-Si:H Thin-film Transistors under Electrical Stresses
3.1 Introduction ------------------------------------------------------------------------39
3.2 Experimental Procedure ---------------------------------------------------------40
3.3 Results and Discussion -----------------------------------------------------------42
3.3.1 Threshold voltage shift under different stress condition ---------------42
3.3.2 Effective stress duration ----------------------------------------------------43
3.3.3 Degradation mechanisms ---------------------------------------------------46
3.3.4 Illustration of AC stress mechanisms -------------------------------------48
3.4 Conclusions -------------------------------------------------------------------------50
Chapter 4 - Temperature Influence on Photo-leakage-current Characteristics of a-Si:H Thin-film Transistor
4.1 Introduction ------------------------------------------------------------------------56
4.2 Experimental Procedure ---------------------------------------------------------58
4.3 Results and Discussion -----------------------------------------------------------59
4.3.1 Transfer characteristics under dark and light illumination -------------59
4.3.2 Temperature effect -----------------------------------------------------------60
4.3.3 Calculation of parasitic resistance -----------------------------------------62
4.4 Conclusions -------------------------------------------------------------------------64
Chapter 5 - Analysis of the Influence of Trap States on Photo-leakage-current in a-Si:H Thin-film Transistors by UV Irradiation
5.1 Introduction ------------------------------------------------------------------------70
5.2 Experimental Procedure ---------------------------------------------------------72
5.3 Results and Discussion -----------------------------------------------------------73
5.3.1 The evolution of transfer curves
as a function of UV irradiation time ---------------------------------73
5.3.2 Comparison of transfer curves under backlight illumination ----------77
5.3.3 The mechanisms of reducing/increasing photo leakage current -------79
5.4 Conclusions -------------------------------------------------------------------------83
Chapter 6 - Hydrogen-induced Improvements in Electrical Characteristics of a-IGZO Thin-film Transistors
6.1 Introduction ------------------------------------------------------------------------96
6.2 Experimental Procedure ---------------------------------------------------------97
6.3 Results and Discussion -----------------------------------------------------------99
6.3.1 The influence of Hydrogen gas flow --------------------------------------99
6.3.2 Hysteresis measurement ---------------------------------------------------100
6.3.3 X-ray diffraction analysis -------------------------------------------------101
6.3.4 Optical transmittance spectra ---------------------------------------------101
6.3.5 X-ray photoelectron spectroscopy analysis -----------------------------102
6.4 Conclusions -----------------------------------------------------------------------104
Chapter 7 - Moisture-related Anomalous Transfer Characteristics for InGaZnO Thin-film-transistor Under Positive Gate Bias Stress
7.1 Introduction ----------------------------------------------------------------------110
7.2 Experimental Procedure -------------------------------------------------------111
7.3 Results and Discussion ----------------------------------------------------------112
7.3.1 The evolution of threshold voltage shift under bias stress ------------112
7.3.2 Hump in transfer curve ----------------------------------------------------113
7.3.3 H2O environment simulation ---------------------------------------------114
7.3.4 Influence of different electric field --------------------------------------115
7.3.5 Chemical reaction equation -----------------------------------------------115
7.4 Conclusions -----------------------------------------------------------------------116
Chapter 8 - Conclusions and Suggestions for Future Work
8.1 Conclusions -----------------------------------------------------------------------123
8.2 Suggestions for Future Work -------------------------------------------------127
References --------------------------------------------------------------------129

Chapter 1
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Chapter 2
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Chapter 3
[3.1] R. Baeuerle, J. Baumbach, E. Lueder, and J. Siegordner, “A MIM driven display with colour filters on 2” diagonal plastic substrates” SID Int. Symp. Digest Tech. Papers 30, 14 (1999).
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[3.22] Y Uraoka, H Yano, T Hatayama, and T Fuyuki, “Hot carrier effect in low-temperature poly-Si p-ch thin-film transistors under dynamic stress” Jpn. J. Appl. Phys. 41, L13 (2002).
[3.23] K. M. Chang, Y. H. Chung, and G. M. Lin, “Hot carrier induced degradation in the low temperature processed polycrystalline silicon thin film transistors using the dynamic stress” Jpn. J. Appl. Phys. 41, 1941 (2002).

Chapter 4
[4.1] F. B. Ellis Jr, R. G. Gordon, W. Paul, and B. G. Yacobi, “Properties of hydrogenated amorphous silicon prepared by chemical vapor deposition” J .Appl. Phys. 55, 4309 (1984).
[4.2] R. Baeuerle, J. Baumbach, E. Lueder, and J. Siegordner, “A MIM driven display with colour filters on 2” diagonal plastic substrates” SID Int. Symp. Digest Tech. Papers 30, 14 (1999).
[4.3] J. K. Yoon, Y. H. Jang, B. K. Kim, H. S. Choi, B. C. Ahn, and C. Lee, “Voltage dependence of off current in a-SiH TFT under backlight illumination” J. Non-Cryst. Solids 164-166, 747 (1993).
[4.4] M. Akiyama, T. Kiyota, Y. Ikeda, T. Koizumi, M. Ikeda, and K. Suzuki, “A 13.8-in.-diagonal 1-Mpixel TFT-LCD with light-shielded fully self-aligned TFTs” SID Int. Symp. Digest Tech. Papers 26, 158 (1995).
[4.5] C. Y. Liang, F. Y. Gan, P. T. Liu, F. S. Yeh, S. H. L. Chen, and T. C. Chang, “A novel self-Aligned etch-stopper structure with lower photo leakage for AMLCD and sensor applications” IEEE Electron Device Lett. 27, 978 (2006).
[4.6] Y. Yamaji, M. Ikeda, M. Akiyama, and T. Endo, “Characterization of photo leakage current of amorphous silicon thin-film transistors” Jpn. J. Appl. Phys. Part 1 38, 6202 (1999).
[4.7] H. N. Lee, J. Cho, and H. J. Kim, “Relationship between leakage current and the type of passivation layer of hydrogenated amorphous silicon thin-film transistors” Jpn. J. Appl. Phys. Part 1 42, 6678 (2003).
[4.8] A. Sanjoh, N. Ikeda, and K. Komaki, “Off current characteristics of amorphous silicon thin film transistors under gate-side illumination” Thin Solid Films 208, 125 (1992).
[4.9] Y. J. Choi, B. C. Lim, I. K. Woo, J. I. Ryu, and J. Jang, “Low photo-leakage current amorphous silicon thin film transistor with a thin active layer” J. Non-Cryst. Solids 266-269, 1299 (2000).
[4.10] V. Foglietti, L. Mariucci, and G. Fortunato, “Temperature dependence of the transfer characteristics of polysilicon thin film transistors fabricated by excimer laser crystallization” J. Appl. Phys. 85, 616 (1999).
[4.11] P. G. Le Comber and W. E. Spear, “Electronic transport in amorphous silicon films” Phys. Rev. Lett. 25, 509 (1970).
[4.12] R. A. Street. Hydrogenated amorphous silicon. Cambridge: Cambridge University Press, (1991).
[4.13] M. J. Kirton and M. J. Uren, “Capture and emission kinetics of individual Si:SiO2 interface states” Appl. Phys. Lett. 48, 1270 (1986).
[4.14] E. A. Gutiérrez-D, M. J. Deen, and C.Claeys, Low temperature Electronics: Physics, Devices, Circuits, and Applications, San Diego: Academic Press, (2001).
[4.15] S. Sherman, P. Y. Lu, R. A. Gottscho, and S. Wagner, “TFT performance-material quality correlation for a-Si:H deposited at high rates” Mater. Res. Soc. Symp. Proc. 377, 749 (1995).

Chapter 5
[5.1] R. Baeuerle, J. Baumbach, E. Lueder, and J. Siegordner, “A MIM driven display with colour filters on 2” diagonal plastic substrates” SID Int. Symp. Digest Tech. Papers 30, 14 (1999).
[5.2] H. Hosono, K. Nomura, Y. Ogo, T. Uruga, and T. Kamiya, “Factors controlling electron transport properties in transparent amorphous oxide semiconductors” J. Non-Cryst. Solids 354, 2796 (2008).
[5.3] P. Barquinha, L. Pereira, G. Goncalves, R. Martins, and E. Fortunato, “The effect of deposition conditions and annealing on the performance of high-mobility GIZO TFTs” Electrochem. Solid-State Lett. 11, H248 (2008).
[5.4] J. K. Yoon, Y. H. Jang, B. K. Kim, H. S. Choi, B. C. Ahn, and C. Lee, “Voltage dependence of off current in a-SiH TFT under backlight illumination” J. Non-Cryst. Solids 164-166, 747 (1993).
[5.5] M. Akiyama, T. Kiyota, Y. Ikeda, T. Koizumi, M. Ikeda, and K. Suzuki, “A 13.8-in.-diagonal 1-Mpixel TFT-LCD with light-shielded fully self-aligned TFTs” SID Int. Symp. Digest Tech. Papers 26, 158 (1995).
[5.6] C. Y. Liang, F. Y. Gan, P. T. Liu, F. S. Yeh, S. H. L. Chen, and T. C. Chang, “A novel self-aligned etch-stopper structure with lower photo leakage for AMLCD and sensor applications” IEEE Electron Device Lett. 27, 978 (2006).
[5.7] Y. Yamaji, M. Ikeda, M. Akiyama, and T. Endo, “Characterization of photo leakage current of amorphous silicon thin-film transistors” Jpn. J. Appl. Phys. Part 1 38, 6202 (1999).
[5.8] H. N. Lee, J. Cho, and H. J. Kim, “Relationship between leakage current and the type of passivation layer of hydrogenated amorphous silicon thin-film transistors” Jpn. J. Appl. Phys. Part 1 42, 6678 (2003).
[5.9] N. Hirano, N. Ikeda, H. Yamaguchi, S. Nishida, Y. Hirai, and S. Kaneko, “A 33cm-diagonal high-resolution multi-color TFT-LCD with fully self-aligned a-Si:H TFTs” IDRC ’94 Digest, International Display Research Conference, CA, 369 (1994).
[5.10] M. C. Wang, T. C. Chang, P. T. Liu, S. W. Tsao, and J. R. Chen, “Photo-leakage-current characteristic of F incorporated hydrogenated amorphous silicon thin film transistor” Appl. Phys. Lett. 90, 192114 (2007).
[5.11] J. S. Byun, H. B. Jeon, K. H. Lee, and J. Jang, “Effect of Cl incorporation on the stability of hydrogenated amorphous silicon” Appl. Phys. Lett. 67, 3786 (1995).
[5.12] J. H. Choi, C. S. Kim, S. K. Kim, and J. Jang, “Effect of Cl incorporation on the performance of amorphous silicon thin film transistors” J. Appl. Phys. 82, 4081 (1997).
[5.13] Y. Li, C. H. Hwang, C. L. Chen, S. T. Yan, and J. C. Lou, “UV illumination technique for leakage current reduction in a-Si:H thin-film transistors” IEEE Trans. Electron Device 55, 3314 (2008).
[5.14] A. J. Flewitt and W. I. Milne, In: Y. Kuo, editor. Thin film transistors – materials and processes, vol. 1. Amorphous silicon thin film transistors. U.S.A.: Texas A&M University; p. 55 (2004).
[5.15] P. Servati and A. Nathan, “Modeling of the reverse characteristics of a-Si:H TFTs” IEEE Trans. Electron Device 49, 812 (2008).
[5.16] S. Martin, J. Kanicki, N. Szydlo, and A. Rolland, “Analysis of the amorphous silicon thin film transistors behavior under illumination” AM-LCD’ 97, p.211 (1997).

Chapter 6
[6.1] H. Q. Chiang, J. F. Wager, R. L. Hoffman, J. Jeong, and D. A. Keszler, “High mobility transparent thin-film transistors with amorphous zinc tin oxide channel layer” Appl. Phys. Lett. 86, 013503 (2005).
[6.2] E. Fortunato, L. Pereira, P. Barquinha, A. Rego, G. Goçcalves, A. Vilà, J. R. Morante, and R. Martins, “High mobility indium free amorphous oxide thin film transistors” Appl. Phys. Lett. 92, 222103 (2008).
[6.3] H. Yabuta, M. Sano, K. Abe, T. Aiba, T. Den, H. Kumomi, K. Nomura, T. Kamiya, and H. Hosono, “High-mobility thin-film transistor with amorphous InGaZnO4 channel fabricated by room temperature rf-magnetron sputtering” Appl. Phys. Lett. 89, 112123 (2006).
[6.4] D. H. Kim, N. G. Cho, H. G. Kim, and I. D. Kim, “Highly transparent InGaZnO4 thin film transistors using indium-doped ZnO electrodes on plastic substrate” Electrochem. Solid-State Lett. 12, H198 (2009).
[6.5] J. S. Park, T. W. Kim, D. Stryakhilev, J. S. Lee, S. G. An, Y. S. Pyo, D. B. Lee, Y. G. Mo, D. U. Jin, and H. K. Chung, “Flexible full color organic light-emitting diode display on polyimide plastic substrate driven by amorphous indium gallium zinc oxide thin-film transistors” Appl. Phys. Lett. 95, 013503 (2009).
[6.6] J. H. Lee, D. Y. Kim, S. Y. Hong, K. S. Yoon, P. S. Hong, C. O. Jeong, H. Park, S. Y. Kim, S. K. Lim, S. S. Kim, K. Son, T. Kim, J. Kwon, and S. Lee, “World’s largest (15-inch) XGA LCD panel using IGZO oxide TFT” SID Int. Symp. Digest Tech. Papers 39, 625 (2008).
[6.7] J. K. Jeong, H. J. Lee, C. K. Kang, J. H. Choi, K. N. Kang, H. K. Seo, J. Kang, M. Kim, H. Chung, J. H. Jeong, T. K. Ahn, H. Yang, J. Park, Y. Mo, H. D. Kim, and H. K. Chung “12.1-inch WXGA AMOLED display driven by indium-gallium-zinc oxide TFTs array” SID Int. Symp. Digest Tech. Papers 39, 1 (2008).
[6.8] J. I. Song, J. S. Park, H. Kim, Y. W. Heo, J. H. Lee, J. J. Kim, G. M. Kim, and B. D. Choi, “Transparent amorphous indium zinc oxide thin-film transistors fabricated at room temperature” Appl. Phys. Lett. 90, 022106 (2007).
[6.9] C. H. Jung, D. J. Kim, Y. K. Kang, D. H. Yoon, “Transparent amorphous In–Ga–Zn–O thin film as function of various gas flows for TFT applications” Thin Solid Films 517, 4078 (2009).
[6.10] P. Görrn, P. Hölzer, T. Riedl, W. Kowalsky, J. Wang, T. Weimann, P. Hinze, and S. Kipp, “Stability of transparent zinc tin oxide transistors under bias stress” Appl. Phys. Lett. 90, 063502 (2007).
[6.11] B. D. Ahn, H. S. Shin, H. J. Kim, J. S. Park, J. K. Jeong, “Comparison of the effects of Ar and H2 plasmas on the performance of homojunctioned amorphous indium gallium zinc oxide thin film transistors” Appl. Phys. Lett. 93 203506 (2008).
[6.12] S. Takeda, M. Fukawa, “Highly stable hydrogenated gallium-doped zinc oxide thin films grown by DC magnetron sputtering using H2/Ar gas” Thin Solid Films 468, 234 (2004).
[6.13] E. V. Monakhov, J. S. Christensen, K. Maknys, B. G. Svensson, A. Y. Kuznetsov, “Hydrogen implantation into ZnO for n+-layer formation” Appl. Phys. Lett. 87, 191910 (2005).
[6.14] D. G. Kim, S. Lee, G. H. Lee, S. C. Kwon, “Effects of hydrogen gas on properties of tin-doped indium oxide films deposited by radio frequency magnetron sputtering method” Thin Solid Films 515, 6949 (2007).
[6.15] Y. Kuo, Thin film transistors – materials and processes. Amorphous silicon thin film transistors, vol. 1. Kluwer Academic Publishers; 2004.
[6.16] K. Chatty, S. Banerjee, T. P. Chow, and R. J. Gutmann. “Hysteresis in transfer characteristics in 4H–SiC depletion/accumulation-mode MOSFETs” IEEE Electron Device Lett. 23, 330 (2002).
[6.17] J. H. Lee, K. S. Shin, J. H. Park, and M. K. Han. “Experimental study of the hysteresis in hydrogenated amorphous silicon thin-film transistors for an active matrix organic light-emitting diode” J. Kor. Phy. Soc. 48, S76 (2006).
[6.18] Y. F. Lu, H. Q. Ni, Z. H. Mai, and Z. M. Ren, “The effects of thermal annealing on ZnO thin films grown by pulsed laser deposition” J. Appl. Phys. 88, 498 (2000).
[6.19] M. Chen, Z. L. Pei, C. Sun, L. S. Wen, and X. Wang, “Surface characterization of transparent conductive oxide Al-doped ZnO flms” J. Cryst. Growth. 220, 254 (2000).
[6.20] G. H. Kim, H. S. Kim, H. S. Shin, B. D. Ahn, K. H. Kim, and H. J. Kim. “Inkjet-printed InGaZnO thin film transistor” Thin Solid Films 517, 4007 (2009).

Chapter 7
[7.1] H. Yabuta, M. Sano, K. Abe, T. Aiba, T. Den, H. Kumomi, K. Nomura, T. Kamiya, and H. Hosono, “High-mobility thin-film transistor with amorphous InGaZnO4 channel fabricated by room temperature rf-magnetron sputtering” Appl. Phys. Lett. 89, 112123 (2006).
[7.2] E. Fortunato, L. Pereira, P. Barquinha, A. Rego, G. Goçcalves, A. Vilà, J. Morante, and R. Martins, “High mobility indium free amorphous oxide thin film transistors” Appl. Phys. Lett. 92, 222103 (2008).
[7.3] H. Q. Chiang, J. F. Wager, R. L. Hoffman, J. Jeong, and D. A. Keszler, “High mobility transparent thin-film transistors with amorphous zinc tin oxide channel layer” Appl. Phys. Lett. 86, 013503 (2005).
[7.4] J. S. Park, T. W. Kim, D. Stryakhilev, J. S. Lee, S. G. An, Y. S. Pyo, D. B. Lee, Y. G. Mo, D. U. Jin, and H. K. Chung, “Flexible full color organic light-emitting diode display on polyimide plastic substrate driven by amorphous indium gallium zinc oxide thin-film transistors” Appl. Phys. Lett. 95, 013503 (2009).
[7.5] D. H. Kim, N. G. Cho, H. G. Kim, and I. D. Kim, “Highly transparent InGaZnO4 thin film transistors using indium-doped ZnO electrodes on plastic substrate” Electrochem. Solid-State Lett. 12, H198 (2009).
[7.6] J. S. Park, J. K. Jeong, H. J. Chung, Y. G. Mo, and H. D. Kim, “Electronic transport properties of amorphous indium-gallium-zinc oxide semiconductor upon exposure to water” Appl. Phys. Lett. 92, 072104 (2008).
[7.7] D. Kang, H. Lim, C. Kim, and I. Song, “Amorphous gallium indium zinc oxide thin film transistors: Sensitive to oxygen molecules” Appl. Phys. Lett. 90, 192101 (2007).
[7.8] S. Y. Sung, J. H. Choi, U. B. Han, K. C. Lee, J. H. Lee, J. J. Kim, W. Lim, S. J. Pearton, D. P. Norton, and Y. W. Heo, “Effects of ambient atmosphere on the transfer characteristics and gate-bias stress stability of amorphous indium-gallium-zinc oxide thin-film transistors” Appl. Phys. Lett. 96, 102107 (2010).
[7.9] Y. C. Chen, T. C. Chang, H. W. Li, S. C. Chen, J. Lu, W. F. Chung, Y. H. Tai, and T. Y. Tseng, “Bias-induced oxygen adsorption in zinc tin oxide thin film transistors under dynamic stress” Appl. Phys. Lett. 96, 262104 (2010).
[7.10] J. K. Jeong, H. W. Yang, J. H. Jeong, Y. G. Mo, and H. D. Kim, “Origin of threshold voltage instability in indium-gallium-zinc oxide thin film transistors” Appl. Phys. Lett. 93, 123508 (2008).
[7.11] P. T. Liu, Y. T. Chou, and L. F. Teng, “Environment-dependent metastability of passivation-free indium zinc oxide thin film transistor after gate bias stress” Appl. Phys. Lett. 95, 233504 (2009).
[7.12] C. T. Tsai, T. C. Chang, S. C. Chen, I. Lo, S. W. Tsao, M. C. Hung, J. J. Chang, C. Y. Wu, and C. Y. Huang, “Influence of positive bias stress on N2O plasma improved InGaZnO thin film transistor” Appl. Phys. Lett. 96, 242105 (2010).
[7.13] M. E. Lopes, H. L. Gomes, M. C. R. Medeiros, P. Barquinha, L. Pereira, E. Fortunato, R. Martins, and I. Ferreira, “Gate-bias stress in amorphous oxide semiconductors thin-film transistors” Appl. Phys. Lett. 95, 063502 (2009).
[7.14] F. R. Libsch and J. Kanicki, “Bias-stress-induced stretched-exponential time dependence of charge injection and trapping in amorphous thin-film transistors” Appl. Phys. Lett. 62, 1286 (1993).
[7.15] J. M. Lee, I. T. Cho, J. H. Lee, and H. I. Kwon, “Bias-stress-induced stretched-exponential time dependence of threshold voltage shift in InGaZnO thin film transistors” Appl. Phys. Lett. 93, 093504 (2008).
[7.16] C. F. Huang, C. Y. Peng, Y. J. Yang, H. C. Sun, H. C. Chang, P. S. Kuo, H. L. Chang, C. Z. Liu, and C. W. Liu, “Stress-induced hump effects of p-channel polycrystalline silicon thin-film transistors” IEEE Electron Device Lett. 29, 1332 (2008).