Abstract:
PROBLEM TO BE SOLVED: To provide a manufacturing method of a package substrate which can realize a high density fine circuit pattern by preventing undercut formed by VIA open and flash etching. SOLUTION: The method comprises: a stage of manufacturing a base substrate in which an internal layer circuit pattern is formed by a designated masking process; a stage of forming an insulating layer, performing interlayer electrical insulation, on the base substrate; a stage of forming VIA hole performing interlayer electrical conduction with respect to the insulating layer; a stage of forming seed layer on the insulating layer in which the VIA hole has been formed; and a stage of forming an external layer circuit pattern on the seed layer by the designated masking process. The seed layer is partially and selectively processed in the flash etching in order to prevent the undercut occurring in the VIA open and the external layer circuit pattern. COPYRIGHT: (C)2006,JPO&NCIPI
Abstract:
A multilayer printed circuit board (5010) comprises a core board (5030) and, as constructed on both sides thereof, a buildup wiring layer obtainable by building up an interlayer resin insulating layer (5050, 5150) and a conductor layer (5058, 5158) alternately with said conductor layers (5058, 5158) being interconnected by via holes (5160). The via holes (5060, 5160) are formed immediately over plated-through holes (5036) in the manner of plugging the through holes (5016) in the core board (5030). In a process for manufacturing the multilayer printed circuit board (5010), the through holes (5016) are pierced by laser light to be not larger than 200 µm in diameter.
Abstract:
A process and product manufactured by the process is revealed whereby resistors (16) can be manufactured integral a printed circuit board (10, 13) by plating the resistors onto an insulative substrate (10). Uniformization of the insulative substrate by etching and oxidation of the plated resistor are revealed as techniques for improving the uniformity and consistency of the plated resistors.
Abstract:
To provide a method of producing a multilayer printed wiring board that can be intended to have low-profile, light-weight and high-density wiring of a printed wiring board, and a multilayer printed wiring board produced by the method of producing a multilayer printed wiring board, the double-sided substrate is produced by the steps of forming an insulating resin layer (2) on a metal foil (1); of forming a via hole (3) in the insulating resin layer (2); of forming a first circuit pattern (4) on the insulating resin layer (2) and forming a conductive layer (5) in the via hole (3), by plating; and of etching the metal foil (1) to form it into a second circuit pattern (6). The produced double-sided substrate (7) is used as a core substrate for producing multilayer printed wiring board by a laminate-en-bloc or a build-up method.