Patent ID: 6083340
Filing Date: 2000-07-04
Classification: B32B,H05K,Y10T

Abstract:
A process for manufacturing a multi-layer circuit board comprising:applying metal foil circuit patterns to the top and bottom surfaces of a prepreg to form an inner substrate;applying a plurality of prepregs provided with metal foil circuit patterns on one surface to said inner substrate to form a laminate of alternating layers of prepregs and metal foil circuit patterns;heating said laminate under pressure to thereby cure said prepregs and bond said metal foil circuit patterns to said prepregs;forming a plurality of through-holes in said laminate where electrical connections between said metal foil circuit patterns are desired;applying a colloidal dispersion of ultrafine metal particles of the independent dispersion type to the inner surface and around the circumference of both openings of said through-holes; andheating said laminate to calcine said colloidal dispersion and form a metal particle film of ultrafine metal particles only, said metal particle film being free of resins, binders, and other non-conductive materials.