Method of producing a three-dimensional wiring board

Abstract

Small projections are arranged on a molding surface of at least one of an upper die half and a lower die half constituting a molding die, and a predetermined number of conductor circuits each including small projections are formed on the molding surface by electrically plating. A predetermined number of conductor circuits are formed on the molding surface of other die half in the same manner. Subsequently, the molding surfaces of both the die halves are brought in pressure contact with each other so that the electrically plated layers each including small projections on the molding surface are connected electrically. Thereafter, the hollow space between both the die halves is filled with a predetermined resin, whereby the conductor circuits are reversely secured to the resultant molded product to complete production of a three-dimensional wiring board. After electronic components are assembled on the three-dimensional wiring board, the resin is removed from the molded product by dissolving the resin. Consequently, a hollow three-dimensional wiring structure is formed. Thus, three-dimensional conductor circuits which are electrically connected to each other at predetermined positions are formed on the front and rear surfaces of molded product. Thus, the three-dimensional wiring board can be produced at a high efficiency without any necessity for complicated steps and actuation. An electronic circuit module produced by assembling electronic components on the three-dimensional wiring board assures that signals can be processed at a high speed.