PURPOSE: To enable a semiconductor package to be enhanced in mounting density, easily replaced, and easily repaired by a method wherein molten solder- repellent insulating agent high in thermal resistance is attached to the surface of solder resist resin.

CONSTITUTION: Photosensitive non-epoxy photoresist is printed on a semiconductor pattern of a circuit board 10 where a copper foil 25 is not bonded, and epoxy liquid solder resist 26 such as epoxy acrylate resin or the like is printed on a non-conductive pattern. Heat-resistant insulating ceramic coating agent wherein 0.1 to 10% of transparent amorphous fluororesin (cytop) is added as organic binder is applied onto all the surface of the circuit board 10 to form a film, the surface of a ceramic coating 24 is coated with a cytop coating. Therefore, the ceramic coating 24 serves the same as a plating resist, so that solder bridges are hardly generated between the adjacent lead pins of e semiconductor, which is conducive to the improvement of a mounting operation in efficiency.