Formation of Fine Pitch Solder Bumps on Polytetrafluoroethylene Printed Circuit Board using Dry Film Photoresist

Dry Film Photoresist를 이용한 테프론 PCB 위 미세 피치 솔더 범프 형성

  • 이정섭 (한국과학기술원 재료공학과) ;
  • 주건모 (한국과학기술원 재료공학과) ;
  • 전덕영 (한국과학기술원 재료공학과)
  • Published : 2003.11.01

Abstract

We demonstrated the applicability of dry film photoresist (DFR) in photolithography process for fine pitch solder bumping on the polytetrafluoroethylene (PTFE/Teflon) printed circuit board (PCB). The copper lines were formed with $100\;{\mu}m$ width and $18\;{\mu}m$ thickness on the PTFE test board, and varying the gaps between two copper lines in a range of $100-200\;{\mu}m$. The DFRs of $15\;{\mu}m$ thickness were laminated by hot roll laminator, by varying laminating temperature from $100^{\circ}C\;to\;150^{\circ}C$ and laminating speed. We found the optimum process of DFR lamination on PTFE PCB and accomplished the formation of indium solder bumps. The optimum lamination condition was temperature of $150^{\circ}C$ and speed of about 0.63 cm/s. And the smallest size of indium solder bump was diameter of $50\;{\mu}m$ with pitch of $100\;{\mu}m$.

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