| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to form simply bumps of a shape suitable for mounting a bare chip on a printed circuit board. SOLUTION: A printed circuit board 10 of a structure, wherein circuit patterns 12 and 13 are respectively provided on the surface and rear of a substrate 11 consisting of a glass fiber-filled epoxy resin, is positioned between a top force provided with recessed places 24 corresponding to the shape and arrangement of bumps, which should be made to form, and a planar bottom force and is inserted between the top and bottom forces. The positioning is performed by a method wherein positioning pins 28 provided on the lower surface of the above top force are fitted into positioning holes 18 formed in the board 10. The board 10 is heated at a temperature of 180 deg.C higher than 120 deg.C of the glass transition point of the used epoxy resin, and is pressed by the top and bottom forces to make the above cone-shaped bumps faithful to the shape of the places 24 form on the patterns 12. |
