Patent ID: 7520053
Filing Date: 2009-04-21
Classification: H01L,H05K,Y10T

Abstract:
1. A method for manufacturing a bump-attached wiring circuit board in which bumps are formed on a wiring circuit, comprising the steps of: (aa) laminating a protective film over a wiring circuit formation side of a metal foil having a thickness equal to the sum of the thickness of the wiring circuit and the height of the bumps to be formed on the wiring circuit, and forming a bump formation etching mask on a bump formation side of the metal foil; (bb) forming bumps of a predetermined height by half-etching the metal foil from the side with the bump formation etching mask; (cc) removing the bump formation etching mask, and then forming a metal thin film layer over the bumps, the metal thin film layer being composed of a different metal from that of the metal foil; (dd) forming a polyimide precursor layer over the metal thin film layer so as to bury the bumps; (ee) etching the polyimide precursor layer and forming an insulating layer above the metal thin film layer in a predetermined thickness by imidation; (ff) removing the protective film provided to the wiring circuit formation side of the metal foil, and then forming a wiring circuit formation etching mask on this wiring circuit formation side; (gg) forming a wiring circuit in a predetermined thickness by half-etching the metal foil from the wiring circuit formation etching mask side; and (hh) removing the wiring circuit formation etching mask, and then providing a cover coat layer to the wiring circuit.