한국정보통신학회논문지 (Journal of the Korea Institute of Information and Communication Engineering)

  • 제21권3호
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  • Pages.578-584
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  • 2017
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  • 2234-4772(pISSN)
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  • 2288-4165(eISSN)
한국정보통신학회 (The Korea Institute of Information and Commucation Engineering)
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SiO2 버퍼층을 갖는 PET 기판위에 증착한 IZTO 박막의 전기적 및 광학적 특성

Electrical and Optical Properties of the IZTO Thin Film Deposited on PET Substrates with SiO2 Buffer Layer

  • Park, Jong-Chan (Department of Electronic Engineering, Inha University) ;
  • Joung, Yang-Hee (Department of Electrical & Semiconductor Engineering, Chonnam National University) ;
  • Kang, Seong-Jun (Department of Electrical & Semiconductor Engineering, Chonnam National University)
  • 투고 : 2016.10.06
  • 심사 : 2016.10.23
  • 발행 : 2017.03.31
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초록

PET (Polyethylene terephthalate) 플라스틱 기판 위에 IZTO (In-Zn-Sn-O) 박막을 증착하기 전에, $SiO_2$ 버퍼층을 전자빔 증착 방법으로 100 nm 의 두께로 증착하였다. IZTO 박막은 RF 마그네트론 스퍼터링법으로 RF 파워는 30~60 W 로, 공정 압력은 1~7 mTorr 로 변화시켜가며 $SiO_2$/PET 에 증착하여 IZTO 박막의 구조적, 전기적, 광학적 특성을 분석하였다. RF 파워 50 W 와 공정 압력 3 mTorr 에서 증착한 IZTO 박막이 $4.53{\times}10^{-3}{\Omega}$ 의 제일 큰 재료평가지수와 이때 $4.42{\times}10^{-4}{\Omega}-cm$ 의 비저항과 $27.63{\Omega}/sq.$ 의 면저항으로 가장 우수한 전기적 특성을 보였고, 가시광 영역 (400~800 nm) 에서의 평균 투과도도 81.24 % 로 가장 큰 값을 나타내었다. AFM 으로 IZTO 박막의 표면 형상을 관찰한 결과, 모든 IZTO 박막이 핀홀이나 크랙 같은 결함이 없는 표면을 가지며, RF 파워 50 W 와 공정 압력 3 mTorr에서 증착한 박막이 1.147 nm 의 가장 작은 표면 거칠기를 나타내었다. 이로부터 $SiO_2$/PET 구조위에 증착한 IZTO 박막이 차세대 플렉시블 디스플레이 소자에 응용될 수 있는 매우 유망한 재료임을 알 수 있었다.

$SiO_2$ buffer layer (100 nm) has been deposited on PET substrate by electron beam evaporation. And then, IZTO (In-Zn-Sn-O) thin film has been deposited on $SiO_2$/PET substrate with different RF power of 30 to 60 W, working pressure, 1 to 7 mTorr, by RF magnetron sputtering. Structural, electrical and optical properties of IZTO thin film have been analyzed with various RF powers and working pressures. IZTO thin film deposited on the process condition of 50 W and 3 mTorr exhibited the best characteristics, where figure of merit was $4.53{\times}10^{-3}{\Omega}^{-1}$, resistivity, $4.42{\times}10^{-4}{\Omega}-cm$, sheet resistance, $27.63{\Omega}/sq.$, average transmittance (400-800 nm), 81.24%. As a result of AFM, all the IZTO thin film has no defects such as pinhole and crack, and RMS surface roughness was 1.147 nm. Due to these characteristics, IZTO thin film deposited on $SiO_2$/PET structure was found to be a very compatible material that can be applied to the next generation flexible display device.

키워드

참고문헌

  1. N. Ito, Y. Sato, P. K. Song, A. Kaijio, K. Inoue, Y. Shigesato, "Electrical and Optical Properties of Amorphous Indium Zinc Oxide Films," Thin solid Films, vol. 496, pp. 99-103, Sep. 2005.
  2. K. H. Lee and H. W. Jang, "Mechanism for The Increase of Indium-Tin-Oxide Work Function by $O_2$ Inductively Coupled Plasma Treatment," Journal of Applied Physics, vol. 95, pp. 586-590, Jan. 2004. https://doi.org/10.1063/1.1633351
  3. H. Zhuang, J. Yan, C. Xu, D. Meng, "Transparent Conductive $Ga_2O_3$/Cu/ITO Multilayer Films Prepared on Flexible Substrates at Room Temperature," Applied Surface Science, vol. 307, pp. 241-245, Apr. 2014. https://doi.org/10.1016/j.apsusc.2014.04.020
  4. B. Houng, S. L. Lin, S. W. Chen, A. Wang, "Influence of An $In_2O_3$ Buffer Layer on The Properties of ITO Thin Films," Ceramics International, vol. 37, pp. 3397-3403, Jun. 2011. https://doi.org/10.1016/j.ceramint.2011.05.142
  5. T. Ishida, H. Kobayashi, Y. Nakato, "Structures and Properties of Electron Beam Vaporated Indium Tin Oxide Films as Studied by Xray Photoelectron Spectroscopy and Work Function Measurements," Journal of Applied Physics, vol. 73, pp. 4344-4350, May 1993. https://doi.org/10.1063/1.352818
  6. J. H. Kim, K. A. Jeon, G. H. Kim, S. Y. Lee, "Electrical, Structural, and Optical Properties of ITO Tin Films Prepared at Room Temperature by Pulsed Laser Deposition," Applied Surface Science, vol. 252, pp. 4834- 4832, Nov. 2005.
  7. C. Jang, K. Kim, K. C. Choi, "Flexible Photoluminescent Display Fabricated With Low-Temperature Process Using PET Substrates," Journal of display technology, vol. 8, pp. 250-255, May 2012. https://doi.org/10.1109/JDT.2011.2177242
  8. D. Y. Lee, J. R. Lee, G. H. Lee, P. K. Song, "Study on In-Zn-Sn-O and In-Sn-Zn-O Films Deposited on PET Substrate by Magnetron Co-sputtering System," Surface & Coating Technology, vol. 202, pp. 5718-5723, Jun. 2008. https://doi.org/10.1016/j.surfcoat.2008.06.091
  9. Y. R. Denny, S. Y. Lee, K. I. Lee, S. J. Seo, S. K. Oh, H. J. Kang, S. Heo, J. G. Chung, J. C. Lee, S. Tougaard, "Effects of Gas Environment on Electronic and Optical Properties of Amorphous Indium Zinc Tin Oxide Thin Films," Journal of Vacuum Science & Technology A, vol. 31, pp. 031508-1-7, Apr. 2013. https://doi.org/10.1116/1.4801023
  10. B. J. Woo, J. S. Hong, S. T. Kim, S. H. Park, J. J. Kim, "Effect of A $SiO_2$ Buffer Layer on The Characteristics of $In_2O_3-ZnO-SnO_2$ Films Deposited on PET Substrates," Journal of the Korean Physical Society, vol. 48, pp. 1579- 1582, Jun. 2006.
  11. X. Ding, J. Yan, T. Li, L. Zhang, "Effect of $SiO_2$ Buffer Layer Thickness on The Properties of ITO/Cu/ITO Multilayer Films Deposited on Polyethylene Terephthalate Substrates," Vacuum, vol. 86, pp. 443-447, Sep. 2011. https://doi.org/10.1016/j.vacuum.2011.09.005
  12. S. H. Kwon, Y.M. Kang, Y.R. Cho, S.H. Kim, P.K. Song, "Effect of $TiO_2$ Buffer Layer Thickness on Properties of IZTO Films Deposited on Flexible Substrate," Surface & Coatings Technology, vol. 205, pp.S312-S317, Aug. 2010. https://doi.org/10.1016/j.surfcoat.2010.08.019
  13. X. Ding, J. Yan, T. Li, L. Zhang, "Transparent Conductive ITO/Cu/ITO Films Prepared on Flexible Substrates at Room Temperature," Applied Surface Science, vol. 258, pp. 3082-3085, Nov. 2011.
  14. C. M. Lee, A. Park, Y. J. Cho, M. W. Park, W. I. Lee, H. W. Kim, "Influence of ZnO Buffer Layer Thickness on The Electrical and Optical Properties of Indium Zinc Oxide Thin Films Deposited on PET Substrates," Ceramics International, vol. 34, pp. 1093-1096, Oct. 2007.
  15. G. Haacke, "New Figure of merit for Transparent Conductors," Journal of Applied Physics, vol. 32, pp. 4086- 4089, Aug. 1976.