MULTILAYER WIRING BOARD AND MANUFACTURE THEREOF

PROBLEM TO BE SOLVED: To provide a multilayer wiring board having high reliability by a method, wherein wiring patterns which are formed on a plurality of layers are surely connected electrically between the layers. SOLUTION: In this multilayer wiring board, many layers of film substrates 50, in each if which a wiring pattern 24 is formed on one face of a resin film 10 and in each if which a bonding layer 14 is formed on the other face are laminated via bonding layers 14, and wiring patterns 24, 46 are electrically connected between the layers via respective vias 24, in which a conductive resin is filled into via holes 18 which pass through the resin films 10 and the bonding layers 14. Connecting protrusion which creeps into each via hole 18 to be bonded to the conductive resin is formed in the part of the wiring patterns 46, corresponding to the position of the via 20 in film substrate 60 of an adjacent layer.