Formation of fine pitch solder bumps on polytetrafluoroethylene printed circuit board using dry film photoresist

Author

Lee, Jung-Sub ; Chu, Kun-Mo ; Park, Hyo-Hoon ; Jeon, Duk Young

Author_Institution

Dept. of Mater. Sci. & Eng., Korea Adv. Inst. of Sci. & Technol., Daejeon, South Korea

fYear

2004

fDate

2004

Firstpage

117

Lastpage

122

Abstract

We demonstrated the applicability of dry film photoresists (DFR) in photolithography process for fine pitch bumping on the polytetrafluoroethylene (PTFE/Teflon®) printed circuit board (PCB). The copper lines were formed with 100μm width and 18μm thickness on the PTFE test board, and varying the gaps between two copper lines in a range of 100-200μm. The DFRs of 15μm thickness were laminated by hot roll laminator, by varying laminating temperature from 100°C to 150°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°C and speed of about 0.63cm/s. And the smallest size of indium solder bump was diameter of 50μm with pitch of 100μm.

Keywords

chip-on-board packaging; copper; fine-pitch technology; flip-chip devices; indium; photoresists; printed circuit manufacture; soldering; ultraviolet lithography; 100 to 150 C; Cu; In; UV exposure; copper lines; dry film photoresists; fine pitch solder bumps; flip chip on board; flip chip technology; hot roll laminator; indium solder bumps; optimum process; photolithography process; polytetrafluoroethylene printed circuit board; varying laminating temperature; Copper; Dielectric constant; Dielectric losses; Dielectric materials; Dielectric substrates; Flip chip; Lamination; Optical films; Printed circuits; Resists;

fLanguage

English

Publisher

ieee

Conference_Titel

Asian Green Electronics, 2004. AGEC. Proceedings of 2004 International IEEE Conference on the

Print_ISBN

0-7803-8203-X

Type

conf

DOI

10.1109/AGEC.2004.1290883

Filename

1290883