Thick Film Resistors with Low Tolerance Using Photosensitive Polymer Resistor Paste

감광성 폴리머 저항 페이스트를 이용한 Low Tolerance 후막 저항체

  • Kim, Dong-Kook (Department of Chemistry & Applied Chemistry, Hanyang University) ;
  • Park, Seong-Dae (Department of Chemistry & Applied Chemistry, Hanyang University) ;
  • Lee, Kyu-Bok (Korea Electronics Technology Institute) ;
  • Kyoung, Jin-Bum (Department of Chemistry & Applied Chemistry, Hanyang University)
  • Received : 2010.03.29
  • Accepted : 2010.05.17
  • Published : 2010.08.10

Abstract

In this research, we intended to improve the tolerance of thick film resistor using photosensitive polymer resistor paste which was fabricated with alkali-solution developable photosensitive resin and conductive carbon black. At first, we investigated the effect of the selection of carbon black and photosensitive resin on the resistance range and tolerance level of polymer thick film resistor (PTFR). And then, a difference in resistance tolerance was evaluated according to the coating methods of photosensitive resistor paste on test board. In case that the photosensitive resistor paste was coated on whole surface of test board using screen printing, large positional tolerance was obtained because the formation of the thick film with uniform thickness was difficult. On the other hand, when the paste was coated with roller, the resistive thick film with uniform thickness was formed on the whole board area and the result of resistance evaluation showed low tolerance in ${\pm}10%$ range. The tolerance of PTFR could be improved by combination of the precise patterning using photo-process and the coating process for the resistive thick film with uniform thickness.

본 연구에서는 알칼리 현상형 감광성 수지재료와 전도성 카본블랙을 이용하여 만들어진 감광성 폴리머 저항 페이스트를 이용하여 후막저항체의 허용편차(tolerance)를 개선하고자 하였다. 먼저 카본블랙과 감광성 수지의 선택이 폴리머 후막저항(polymer thick film resistor, PTFR)의 저항값의 범위와 허용편차의 수준에 미치는 영향을 조사하였다. 이후 테스트 기판상에 감광성 저항 페이스트를 도포하는 방법에 따른 저항값 허용편차의 차이를 평가하였다. 감광성 저항 페이스트를 스크린 인쇄를 이용하여 테스트 기판의 전면에 도포한 경우에는 테스트 기판상에서 균일한 두께의 후막을 형성하기 어렵기 때문에 위치에 따른 저항값의 허용편차가 크게 나타났다. 반면, 롤러를 이용하여 페이스트를 도포하였을 때, 전체 기판 면적에 균일한 두께의 저항체 후막을 형성할 수 있었으며, 저항값 평가 결과 ${\pm}10%$ 이내의 낮은 허용편차를 나타내었다. 포토공정을 이용한 정밀한 패터닝 공정과 롤러를 이용한 균일한 두께의 저항막 도포 공정을 결합함으로써 후막저항의 허용편차를 개선할 수 있었다.

Keywords

References

  1. S. K. Bhattacharya and R. R. Tummala, J. Mater. Sci., Mater. Electron., 11, 253 (2000). https://doi.org/10.1023/A:1008913403211
  2. M. Cases, D. N. de Araujo, N. N. Pham, P. Patel, and B. Archambeault, Adv. Microelectron., July/August 2005, 6 (2005).
  3. W. Jillek and W. K. C. Yung, Int. J. Adv. Manuf. Technol., 25, 350 (2005). https://doi.org/10.1007/s00170-003-1872-y
  4. K. Perala, Proc. 9th Intern. Symp. on Advanced Packaging Materials, 220 (2004).
  5. J. T. Y. Su, 9th Intern. Symp. on Advanced Packaging Materials, 74 (2004).
  6. L. J. Salzano, C. Wilkinson, and P. A. Sandborn, IEEE Trans. Advanced Packaging, 28, 503 (2005). https://doi.org/10.1109/TADVP.2005.848387
  7. IPC-2316 Design Guide for Embedded Passive Device Printed Boards, March (2007).
  8. R. C. Snogren, Presented at IPC Annual Meeting and Technical Conference, October 27, Minneapolis, USA (2004).
  9. P. L. Cheng, S. Y. Y. Leung, T. W. Law, C. K. Liu, J. I. T. Chong, and D. C. C. Lam, IEEE Trans. Components and Packaging Tech., 30, 269 (2007). https://doi.org/10.1109/TCAPT.2007.897968
  10. M. G. Varadarajan, K. J. Lee, S. K. Bhattacharya, A. Bhattacharjee, L. Wan, R. Pucha, R. R. Tummala, and S. Sitaraman, Proc. IEEE Conf. High Density Microsystem Design and Packaging and Component Failure Analysis (HDP '06), 188 (2006).
  11. H. Park, J. IEEK, SD, 45, 72 (2008).
  12. U. S. Patent 6,229,098; 6,256,866 (2001).
  13. U. S. Patent 5,994,997 (1999)
  14. U. S. Patent 6,130,601 (2000).
  15. U. S. Patent 6,030,553 (2000).
  16. A. Dziedzic, L. Rebenklau, L. J. Golonka, and K.-J. Wolter, Microelectron. Reliab., 43, 377 (2003). https://doi.org/10.1016/S0026-2714(02)00346-3
  17. U. S. Patent 6,225,035 (2001).
  18. D. K. Kim, S. D. Park, M. J. Yoo, S. H. Sim, and J. B. Kyoung, J. Korean Ind. Eng. Chem., 20, 622 (2009).
  19. A. Dziedzic, Microelectron. Reliab., 47, 354 (2007). https://doi.org/10.1016/j.microrel.2006.02.016