Journal of the Institute of Electronics Engineers of Korea SD (대한전자공학회논문지SD)

The Institute of Electronics and Information Engineers (대한전자공학회)
권호 표지

A Printing Process for Source/Drain Electrodes of OTFT Array by using Surface Energy Difference of PVP (Poly 4-vinylphenol) Gate Dielectric

PVP(Poly 4-vinylphenol) 게이트 유전체의 표면에너지 차이를 이용한 유기박막트랜지스터 어레이의 소스/드레인 전극 인쇄공정

  • Received : 2010.12.23
  • Accepted : 2011.02.10
  • Published : 2011.03.25
Download PDF
⟨ Previous Next ⟩

Abstract

In this paper, we proposed a simple and high-yield printing process for source and drain electrodes of organic thin film transistor (OTFT). The surface energy of PVP (poly 4-vinylphenol) gate dielectric was decreased from 56 $mJ/m^2$ to 45 $mJ/m^2$ by adding fluoride of 3000ppm into it. Meanwhile the surface energy of source and drain (S/D) electrodes area on the PVP was increased to 87 $mJ/m^2$ by treating the areas, which was patterned by photolithography, with oxygen plasma, maximizing the surface energy difference from the other areas. A conductive polymer, G-PEDOT:PSS, was deposited on the S/D electrode areas by brushing painting process. With such a simple process we could obtain a high yield of above 90 % in $16{\times}16$ arrays of OTFTs. The performance of OTFTs with the fluoride-added PVP was similar to that of OTFTs with the ordinary PVP without fluoride, generating the mobility of 0.1 $cm^2/V.sec$, which was sufficient enough to drive electrophoretic display (EPD) sheet. The EPD panel employing the OTFT-backpane successfully demonstrated to display some patterns on it.

본 논문에서는 간단하면서도 수율 높은 유기박막트랜지스터(OTFT)의 소스/드레인 전극 형성을 위한 인쇄공정을 제안하였다. 게이트 유전체인 PVP (poly 4-vinylphenol)에 불소계 화합물을 3000 ppm 첨가하여 표면에너지를 56 $mJ/m^2$에서 45 $mJ/m^2$로 줄이고, 소스/드레인 전극이 형성될 영역은 포토리소그라피로 형상화 한 후 산소 플라즈마로 선택적으로 표면처리하여 표면에너지를 87 $mJ/m^2$로 높임으로써 표면에너지 차이를 극대화 하였다. G-PEDOT:PSS 전도성 고분자를 브러쉬 인쇄공정으로 소스/드레인 전극 영역 주변에 도포하여 전극을 성형하였으며, OTFT 어레이 ($16{\times}16$)에서 약 90% 가까운 수율을 나타내었다. 불소계 화합물을 첨가한 PVP와 펜타센 반도체를 사용한 OTFT의 성능은 첨가하지 않은 소자와 비교하여 큰 차이가 없었으며, 이동도는 0.1 $cm^2/V.sec$ 로서 전기영동디스플레이(EPD) 시트를 구동하기에 충분한 성능이었다. OTFT 어레이에 EPD 시트를 부착하여 성공적인 작동을 확인하였다.

Keywords

References

  1. T. W. Lee, Y. H. Byun, B. W. Koo, I. N. Kang, Y. Y. Lyn, C. H. Lee, L. S. Pu and S.Y. Lee, Adv. Mater. 17, 2180 (2005). https://doi.org/10.1002/adma.200401672
  2. R. Parashkov, E. Backer, G. Ginev and W. Kowalsky, J. Appl. Phys. 95, 1594 (2004) https://doi.org/10.1063/1.1636524
  3. Mi-young Lee, Myung-Won Lee, Ji-Eun Park, Jong-Seung Park, Chung-Kun Song, Microelectronic Engineering, 87, 1922 (2010) https://doi.org/10.1016/j.mee.2009.11.073
  4. T. Kawase, H. Sirringhaus, R. H. Friend and T. Shimoda, Adv. Mater. 13, 1601 (2001). https://doi.org/10.1002/1521-4095(200111)13:21<1601::AID-ADMA1601>3.0.CO;2-X
  5. M. Lefenfeld, G. Blanchet and J. A. Rogers, Adv. Mater. 15, 1188 (2003). https://doi.org/10.1002/adma.200304841
  6. M. W. Lee, M. Y. Lee, J. C. Choi, J. S. Park and C. K. Song, Org. Electron. 11, 854 (2010). https://doi.org/10.1016/j.orgel.2010.01.028
  7. X. Crispin, F. L. E. Jakobsson, A. Crispin, P. C. M. Grim, P. Andersson, A.Volodin, C. van Haesendonck, M. V. der Auweraer, W. R. Salaneck and M. Berggren, Chem. Mater. 18, 4354 (2006). https://doi.org/10.1021/cm061032+
  8. K. Tvingstedt and O. Inganas, Adv. Mater. (Weinheim, Ger.) 19, 2893 (2007). https://doi.org/10.1002/adma.200602561
  9. J. Ouyang, Q. Xu, C.-W. Chu, Y. Yang, G. Li and J. Shinar, Polymer 45, 8443 (2004). https://doi.org/10.1016/j.polymer.2004.10.001
  10. S. Ashizawa, R. Horikawa and H. Okuzaki, Synth. Met. 153, 5 (2005). https://doi.org/10.1016/j.synthmet.2005.07.214
  11. J. Y. Kim, J. H. Jung, D. E. Lee and J. Joo, Synth. Met. 126, 311 (2002). https://doi.org/10.1016/S0379-6779(01)00576-8
  12. F. Zhang, M. Johansson, M. R. Andersson, J. C. Hummelen and O. Inganas, Adv. Mater. (Weinheim, Ger.) 14, 662 (2002). https://doi.org/10.1002/1521-4095(20020503)14:9<662::AID-ADMA662>3.0.CO;2-N
  13. S. Admassie, F. L. Zhang, A. G. Manoj, M. Svensson, M. R. Andersson and O. Inganas, Sol. Energy Mater. Sol. Cells 90, 133 (2006). https://doi.org/10.1016/j.solmat.2005.02.005
  14. X. Wang, M. Ostblom, T. Johansson, O. Inganas, Thin Solid Film 449, 125 (2004) https://doi.org/10.1016/j.tsf.2003.10.153
  15. F. Xue, Y. Su, K. Varaharamyan, IEEE Transactions on Electron Device 52, 1982 (2005) https://doi.org/10.1109/TED.2005.855062
  16. A. Blumel, A. Klug, S. Eder and U. Scherf, Org. Electron. 8, 389, (2007) https://doi.org/10.1016/j.orgel.2007.01.009
  17. B. J. de Gans, E. Kazancioglu, W. Meyer, and U. S. Schubert, Macromol. Rapid Commun. 25, 292 (2004) https://doi.org/10.1002/marc.200300148
  18. 추병권, 최정수, 김건정, 이선희, 박규창, 장진, 한국진공학회지 15권 4호, 354 (2006)
  19. K. S. Lee, G. B. Blanchet, F. Gao and Y. L. Loo, Appl. Phys. Lett. 86, 074102 (2005) https://doi.org/10.1063/1.1862345
  20. J. Z. Wang, Z. H. Zheng, H. W. Li, W. T. S. Huck and H. Sirringhaus, Nature Materials 3, 171 (2004) https://doi.org/10.1038/nmat1073
  21. S. S. Kim, S. I. Na, J. Jo, G. Y. Tae and D. Y. Kim, Adv. Mater. 19, 4410 (2007) https://doi.org/10.1002/adma.200702040
  22. M. OOE, R. Satoh, S. Naka, H. Okada and H. Onagawa, Jpn. J. Appl. Phys. 42, 4529 (2003) https://doi.org/10.1143/JJAP.42.4529
  23. 변현숙, 허영헌, 정현, 황성범, 송정근, 대한전자공학회 하계합동학술대회 논문집 27권 1호, 375 (2004)
  24. 하종욱, 박인준, 이수복, 고분자과학과 기술, 13권 6호, 744 (2002)
  25. E. F. Hare, E. G. Shafrin and W. A. Zisman, J. Colloid Sci. 5, 236 (1954)