Processes for manufacturing flexible wiring boards
AssigneeSony Chemicals Corp.
InventorsHiroyuki Hishinuma, Hideyuki Kurita, Ryo Ito, Masayuki Nakamura
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Abstract
A process for manufacturing a flexible wiring board according to the present invention includes growing metal bumps (16) using a mask film patterned by photolithography. Fine openings are formed in a polyimide film with good precision allowing fine metal bumps (16) to be formed with good precision. After metal bumps (16) have been formed, the mask film is removed and a liquid resin material is applied and dried to form a coating, which is then cured into a resin film. The coating can be etched at surface portions during coating stage to expose the tops of metal bumps (16).
Claims13
A process for manufacturing a flexible wiring board comprising the steps of:
- forming a mask film above a metal foil;
- patterning said mask film by exposure and development;
- removing portions of said mask film to provide exposed portions of said metal foil and residual portions of said mask film;
- growing metal bumps on the exposed portions of said metal foil;
- removing the residual portions of said mask film after metal bumps have been grown;
- applying a liquid resin material to form a resin material coating on said metal foil and over said metal bumps;
- applying a second resin material coating over the resin material coating and subsequently etching to provide a coplanar resin material coating;
- and
- curing said coplanar resin material coating into a resin film.
Dependencies are inferred from the claim text.