摘要 |
This invention relates to a method for forming solder bumps on a circuit board, which is formed with a solder resist and pads thereon and the pads are exposed from the solder resist. The steps of the method mainly are: Firstly, strengthen the solder resist by ultraviolet rays and then rough the solder resist by plasma treatments. Next, lay over a photosensitive dry film onto the solder resist and form openings on the photosensitive dry film for exposing the correspondent pads by exposure and development treatments. Last, form spherical solder bumps on the pads within the openings and remove the photosensitive dry film.
|