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Bias and Light-Induced Instabilities in a-IGZO Thin Film Transistors

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Handbook of Visual Display Technology

Abstract

Instabilities due to various causes have been a major topic of investigation for all thin-film transistors (TFTs). Permanent or metastable changes in the current voltage characteristics are induced by combinations of gate and drain voltage, aging, and environmental effects, as well as exposure to light. Amorphous indium gallium zinc oxide (a-IGZO) TFTs are no exception and these phenomena have been reported at an early stage of the technology development. These devices are relatively stable under moderate positive (negative) gate bias at room temperature (VGS < 15 V), but show increasing positive (negative) shifts of the transfer characteristics under higher positive (negative) VGS. The effects are referred to as positive bias stress (PBS) and negative bias stress (NBS). The latter causes negligible changes under operating conditions. More importantly, large (ΔV > 2 V) negative shifts of the transfer characteristics are observed when the devices are exposed to near or above bandgap radiation. The shifts dramatically increase when a negative bias is simultaneously applied. The effect is referred to as negative bias under illumination stress or NBIS and is obviously important since in display applications the devices operate in the presence of light. PBS and NBIS have received great attention in the scientific literature, which has led to an improved, but by no means complete level of knowledge of the mechanisms involved. The main experiments, the characteristics of these effects, and their interpretation through the models that have been developed are reviewed in this chapter. Unanswered questions and possible future directions of research in this area are identified.

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References

  • Ahn BD, Kim HS, Yun DJ, Park JS, Kim HJ (2014) Improvement of negative bias temperature illumination stability of amorphous IGZO thin-film transistors by water vapor-assisted high-pressure oxygen annealing. ECS J Solid State Sci Technol 3:Q95–Q98

    Article  Google Scholar 

  • Arai T, Sasaoka T (2011) Emergent oxide TFT technologies for next-generation AM-OLED displays. SID 11 Dig 710–713

    Google Scholar 

  • Baek G, Bie L, Abe K, Kumomi H, Kanicki J (2014) Electrical instability of double-gate a-IGZO TFTs with metal source/drain recessed electrodes. IEEE Trans Electron Devices 61:1109–1115

    Article  Google Scholar 

  • Brotherton S (2013) Introduction to thin film transistors. Springer, International Publishing Switzerland

    Google Scholar 

  • Chen C, Kanicki J (2010) Surface potential study of amorphous In–Ga–Zn–O thin film transistors. J Appl Phys 108:114508–5

    Article  Google Scholar 

  • Cheong WS, Park J, Shin JH (2012) Effect of oxygen binding energy on the stability of indium-gallium-zinc-oxide thin-film transistors. ETRI J 34:966–969

    Article  Google Scholar 

  • Chin KK (2011) Local charge neutrality condition, Fermi level and majority carrier density of a semiconductor with multiple localized multi-level intrinsic/impurity defects. J Semicond 32:1120011–1120018

    MathSciNet  Google Scholar 

  • Choi S-H, Han M-K (2012) Effect of channel widths on negative shift of threshold voltage, including stress-induced hump phenomenon in InGaZnO thin-film transistors under high-gate and drain bias stress. Appl Phys Lett 100:0435031–0435034

    Google Scholar 

  • Chowdhury MDH, Migliorato P, Jang J (2010) Light induced instabilities in amorphous indium–gallium–zinc–oxide thin-film transistors. Appl Phys Lett 97:1735061–1735063

    Article  Google Scholar 

  • Chowdhury MDH, Migliorato P, Jang J (2011a) Time-temperature dependence of positive gate bias stress and recovery in amorphous indium-gallium-zinc-oxide thin-film-transistors. Appl Phys Lett 98:1535111–1535113

    Article  Google Scholar 

  • Chowdhury MDH, Ryu SH, Migliorato P, Jang J (2011b) Effect of annealing time on bias stress and light-induced instabilities in amorphous indium–gallium–zinc-oxide thin-film transistors. J Appl Phys Lett 110:1145031–1145035

    Google Scholar 

  • Chowdhury MDH, Migliorato P, Jang J (2013a) Temperature dependence of negative bias under illumination stress and recovery in amorphous indium gallium zinc oxide thin film transistors. Appl Phys Lett 102:1435061–1435063

    Google Scholar 

  • Chowdhury MDH, Migliorato P, Jang J (2013b) unpublished

    Google Scholar 

  • Clark SJ, Robertson J, Lany S, Zunger A (2010) Intrinsic defects in ZnO calculated by screened exchange and hybrid density functionals. Phys Rev B 81:1153111–1153115

    Article  Google Scholar 

  • Flewitt AJ, Powell MJ (2014) A thermalization energy analysis of the threshold voltage shift in amorphous indium gallium zinc oxide thin film transistors under simultaneous negative gate bias and illumination. J Appl Phys 115:1345011–1345017

    Article  Google Scholar 

  • Fortunato E, Barquinha P, Martins R (2012) Oxide semiconductor thin-film transistors: a review of recent advances. Adv Mater 24:2945–2986

    Article  Google Scholar 

  • Fung T-C, Chuang C-S, Nomura K, Shieh DH-P, Hosono H, Kanicki J (2008) Photofield -effects in amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors. J Inf Disp 9:21–29

    Article  Google Scholar 

  • Fung T-C, Abe K, Kumomi H, Kanicki J (2009) Electrical instability of RF sputter amorphous In-Ga-Zn-O thin-film transistors. J Disp Technol 5:452–461

    Article  Google Scholar 

  • Hanyu Y, Domen K, Nomura K, Hiramatsu H, Kumomi H, Hosono H, Kamiya T (2013) Hydrogen passivation of electron trap in amorphous In-Ga-Zn-O thin-film transistors. Appl Phys Lett 103:202114–3

    Article  Google Scholar 

  • Hong S, Lee S, Mativenga M, Jang J (2014) Reduction of negative bias and light instability of a-IGZO TFTs by dual-gate driving. IEEE Electron Device Lett 35:93–95

    Article  Google Scholar 

  • Hung MP, Wang D, Jiang J, Furuta M (2014) Negative bias and illumination stress induced electron trapping at back-channel interface of InGaZnO thin-film transistor. ECS Solid State Lett 3:Q13–Q16

    Article  Google Scholar 

  • Ide K, Kikuchi Y, Nomura K, Kimura M, Kamiya T, Hosono H (2011) Effects of excess oxygen on operation characteristics of amorphous In-Ga-Zn-O thin film transistors. Appl Phys Lett 99:093507–3

    Article  Google Scholar 

  • Janotti A, Van de Walle CG (2007a) Native point defects in ZnO. Phys Rev B 76:1652021–1652022

    Article  Google Scholar 

  • Janotti A, Van de Walle CG (2007b) Hydrogen multicentre bonds. Nat Mater 6:44–47

    Article  Google Scholar 

  • Janotti A, Van de Walle CG (2009) Fundamentals of zinc oxide as a semiconductor. Rep Prog Phys 72:1265011–1265029

    Article  Google Scholar 

  • Jeong JK, Yang HW, Jeong JH, Mo Y-G, Kim HD (2008) Origin of threshold voltage instability in indium-gallium-zinc oxide thin film transistors. Appl Phys Lett 93:1235081–1235083

    Google Scholar 

  • Ji K-H, Kim J-I, Jung H-Y, Park S-Y, Choi R, Kim U-K, Hwang C-S, Lee D, Hwang H, Jeong J-K (2011) Effect of high-pressure oxygen annealing on negative bias illumination stress-induced instability of InGaZnO thin film transistors. Appl Phys Lett 98:103509–3

    Article  Google Scholar 

  • Kamiya T, Nomura K, Hirano M, Hosono H (2008) Electronic structure of oxygen deficient amorphous oxide semiconductor a-InGaZnO4–x: optical analyses and first-principle calculations. Phys Status Solidi 5:3098–3100

    Article  Google Scholar 

  • Kamiya T, Nomura K, Hosono H (2010) Present status of amorphous In–Ga–Zn–O thin-film transistors. Sci Technol Adv Mater 11:0443051–24

    Google Scholar 

  • Kim J-H, Kim U-K, Chung Y-I, Jung J-S, Ra S-H, Jung H-S, Hwang C-S, Jeong J-K, Lee S-Y (2011) The effects of device geometry on the negative bias temperature instability of Hf-In-Zn-O thin film transistors under light illumination. Appl Phys Lett 98:023507–3

    Article  Google Scholar 

  • Kimura M, Nakanishi T, Nomura K, Kamiya T, Hosono H (2008) Trap densities in amorphous-InGaZnO4 thin-film transistors. Appl Phys Lett 92(13):133512–133513

    Article  Google Scholar 

  • Laiho R, Vlasenko LS, Vlasenko MP (2008) Optical detection of magnetic resonance and electron paramagnetic resonance study of the oxygen vacancy and lead donors in ZnO. J Appl Phys 103:1237091–10

    Article  Google Scholar 

  • Lany S, Zunger A (2005) Anion vacancies as a source of persistent photoconductivity in II-VI and chalcopyrite. Phys Rev B 72:0352151–13

    Article  Google Scholar 

  • Lany S, Zakutayev A, Mason TO, Wager JF, Poeppelmeier KR, Perkins JD, Berry JJ, Ginley DS, Zunger A (2012) Surface origin of high conductivities in undoped In2O3 thin films. Phys Rev Lett 108:0168021–0168025

    Article  Google Scholar 

  • Lee JM, Cho IT, Lee JH, Kwon HI (2008) Bias-stress-induced stretched-exponential time dependence of threshold voltage shift in InGaZnO thin film transistors. Appl Phys Lett 93:0935041–0935043

    Google Scholar 

  • Lee K-H, Jung JS, Son KS, Park JS, Kim TS, Choi R, Jeong JK, Kwon J-Y, Koo B, Lee S (2009) The effect of moisture on the photon-enhanced negative bias thermal instability in Ga–In–Zn–O thin film transistors. Appl Phys Lett 95:2321061–2321063

    Google Scholar 

  • Lee W-J, Ryu B, Chang KJ (2009) Electronic structure of oxygen vacancy in crystalline InGaO3(ZnO)m. Physica B 404:4794–4796

    Article  Google Scholar 

  • Lee S, Mativenga M, Jang J (2014) Removal of negative-bias-illumination-stress instability in amorphous-InGaZnO thin-film transistors by top-gate offset structure. IEEE Electron Device Lett 35:930–932

    Article  Google Scholar 

  • Li X, Geng D, Mativenga M, Jang J (2014) High-speed dual-gate a-IGZO TFT-based circuits with top-gate offset structure. IEEE Electron Device Lett 35:461–463

    Article  Google Scholar 

  • Lopes ME, Gomes HL, Medeiros MCR, Barquinha P, Pereira L, Fortunato E, Martins R, Ferreira I (2009) Gate-bias stress in amorphous oxide semiconductors thin-film transistors. Appl Phys Lett 95:0635021–0635023

    Article  Google Scholar 

  • Mativenga M, An S, Jang J (2013a) Bulk accumulation a-IGZO TFT for high current and turn-on voltage uniformity. IEEE Electron Device Lett 34:1533–1535

    Article  Google Scholar 

  • Mativenga M, Hong S, Jang J (2013b) High current stress effects in amorphous-InGaZnO4 thin-film transistors. Appl Phys Lett 102:023503–023504

    Article  Google Scholar 

  • Migliorato P, Seok M, Jang J (2012a) Determination of flat band voltage in thin film transistors: the case of amorphous-indium gallium zinc oxide. Appl Phys Lett 100:0735061–0735064

    Article  Google Scholar 

  • Migliorato P, Chowdhury MDH, Um JG, Seok M, Jang J (2012b) Light/negative bias stress instabilities in indium gallium zinc oxide thin film transistors explained by creation of a double donor. Appl Phys Lett 101:123502–123504

    Article  Google Scholar 

  • Migliorato P, Chowdhury MDH, Um JG, Seok M, Martivenga M, Jang J (2014) Characterization and modelling of a-IGZO thin film transistors. J Disp Technol. doi:10.1109/JDT.2014.2328335

    Google Scholar 

  • Moore WJ (1972) Physical chemistry. Longman Scientific and Technical, London

    Google Scholar 

  • Noh H-K, Chang KJ, Ryu B, Lee W-J (2011) Electronic structure of oxygen-vacancy defects in amorphous In-Ga-Zn-O semiconductors. Phys Rev B 84:1152051–1152058

    Article  Google Scholar 

  • Noh H-K, Park J-S, Chang K-J (2013) Effect of hydrogen incorporation on the negative bias illumination stress instability in amorphous In-Ga-Zn-O thin-film-transistors. J Appl Phys 113:063712–063716

    Article  Google Scholar 

  • Nomura K, Kamiya T, Hirano M, Hosono H (2009) Origins of threshold voltage shifts in room-temperature deposited and annealed a-In–Ga–Zn–O thin-film transistors. Appl Phys Lett 95:0135021–0135023

    Article  Google Scholar 

  • Nomura K, Kamiya T, Hosono H (2010) Interface and bulk effects for bias–light-illumination instability in amorphous-In–Ga–Zn–O thin-film transistors. J SID 18(10):789–795

    Google Scholar 

  • Nomura K, Kamiya T, Ikenaga E, Yanagi H, Kobayashi K, Hosono H (2011a) Depth analysis of subgap electronic states in amorphous oxide semiconductor, a-In-Ga-Zn-O, studied by hard x-ray photoelectron spectroscopy. J Appl Phys 109:0737261–0737268

    Article  Google Scholar 

  • Nomura K, Kamiya T, Hosono H (2011b) Highly stable amorphous In-Ga-Zn-O thin-film transistors produced by eliminating deep subgap defects. Appl Phys Lett 99:0535051–0535053

    Google Scholar 

  • Nomura K, Kamiya T, Hosono H (2013) Effects of diffusion of hydrogen and oxygen on electrical properties of amorphous oxide semiconductor In-Ga-Zn-O. ECS J Solid State Sci Technol 2(1):5–8

    Article  Google Scholar 

  • Oh H, Yoon S-M, Ryu MK, Hwang C-S, Yang S, Park S-HK (2010) Photon-accelerated negative bias instability involving subgap states creation in amorphous In–Ga–Zn–O thin film transistor. Appl Phys Lett 97:1835021–1835023

    Google Scholar 

  • Oh H, Yoon S-M, Ryu M-K, Hwang C-S, Yang S, Park S-HK (2011) Transition of dominant instability mechanism depending on negative gate bias under illumination in amorphous In-Ga-Zn-O thin film transistors. Appl Phys Lett 98:033504–3

    Article  Google Scholar 

  • Powell MJ, Deane SC (1993) Improved defect-pool model for charged defects in amorphous silicon. Phys Rev B 48:10815–10826

    Article  Google Scholar 

  • Ryu B, Noh H-K, Choi E-A, Chang KJ (2010) O-vacancy as the origin of negative bias illumination stress instability in amorphous In–Ga–Zn–O thin film transistors. Appl Phys Lett 97:0221081–0221083

    Google Scholar 

  • Seok MJ, Choi MH, Mativenga M, Geng D, Kim DY, Jang J (2011) A full-swing a-IGZO TFT-based inverter with a top-gate-bias-induced depletion load. IEEE Electron Device Lett 32:1089–1091

    Article  Google Scholar 

  • Shin J-H, Lee J-S, Hwang C-S, Park S-HK, Cheong W-S, Ryu M, Byun C-W, Lee J-I, Chu HY (2009) Light effects on the bias stability of ZnO thin film transistor. ETRI J 31:62–64

    Article  Google Scholar 

  • Son K-S, Jung J-S, Lee K-H, Kim T-S, Park J-S, Park KC, Kwon J-Y, Koo B, Lee S-Y (2010) Highly stable double-gate Ga–In–Zn–O thin-film transistor. IEEE Electron Device Lett 31:812–814

    Article  Google Scholar 

  • Street RA, Tsai CC (1986) Fast and slow states at the interface of amorphous silicon and silicon nitride. Appl Phys Lett 48:1672–1674

    Article  Google Scholar 

  • Suresh A, Muth JF (2008) Bias stress stability of indium gallium zinc oxide channel based transparent thin film transistors. Appl Phys Lett 92:0335021-3

    Article  Google Scholar 

  • Ueoka Y, Ishikawa Y, Bermundo JP, Yamazaki H, Urakawa S, Fujii M, Horita M, Uraoka Y (2014) Density of states in amorphous In-Ga-Zn-O thin-film transistor under negative bias illumination stress. ECS J Solid State Sci Technol 3(9):Q3001–Q3004

    Article  Google Scholar 

  • Um JG, Mativenga M, Jang J (2013) Mechanism of positive bias stress-assisted recovery in amorphous-indium-gallium zinc-oxide thin-film transistors from negative bias under illumination stress. Appl Phys Lett 103:0335011–0335015

    Article  Google Scholar 

  • Um JG, Mativenga M, Migliorato P, Jang J (2014a) Channel length dependence of negative-bias-illumination-stress in amorphous-indium-gallium-zinc-oxide thin film transistors, unpublished

    Google Scholar 

  • Um JG, Mativenga M, Migliorato P, Jang J (2014b) Defect generation in amorphous-indium-gallium-zinc-oxide thin-film transistors by positive bias stress at elevated temperature. J Appl Phys 115:1345021–1345025

    Article  Google Scholar 

  • Wong HSP, Frank DJ, Solomon PM, Wann CHJ, Welser JJ (1999) Nanoscale CMOS. Proc IEEE 87:550–570

    Article  Google Scholar 

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Authors and Affiliations

  1. Advanced Display Research Center and Department of Information Display, Kyung Hee University, Seoul, South Korea

    Piero Migliorato & Jin Jang

  2. Department of Engineering, Electrical Engineering Division, Cambridge University, Cambridge, UK

    Piero Migliorato

Authors
  1. Piero Migliorato
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  2. Jin Jang
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Correspondence to Piero Migliorato .

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Editors and Affiliations

  1. Display Technology Center, Panel Integration Division I, Industrial Technology Research Institute (ITRI), Chutung, Hsinchu, Taiwan

    Janglin Chen

  2. Sheffield Hallam University, Sheffield, United Kingdom

    Wayne Cranton

  3. Veritas et Visus, Temple, Texas, USA

    Mark Fihn

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Migliorato, P., Jang, J. (2016). Bias and Light-Induced Instabilities in a-IGZO Thin Film Transistors. In: Chen, J., Cranton, W., Fihn, M. (eds) Handbook of Visual Display Technology. Springer, Cham. https://doi.org/10.1007/978-3-319-14346-0_179

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