The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 23, 2010
Filed:
May. 31, 2006
Toshinori Kawamura, Hitachi, JP;
Haruo Akahoshi, Hitachi, JP;
Kunio Arai, Ebina, JP;
Hitachi Via Mechanics, Ltd., Kanagawa, JP;
Abstract
There is provided a method for removing molten and scattered Cu and overhang that are generated around a via opening during laser machining in a direct laser via forming method of directly machining an outer-layer copper foil. In a manufacturing method of a printed wiring board of machining the via by laser directly through the copper foil of a copper-clad laminate in which the copper foil is clad on a base material resin, a process for machining the via is carried out in a sequence of (a) a copper foil surface treatment step of forming an oxide film on the surface of said copper foil, (b) a laser via machining step, (c) an alkali treatment step and (d) a molten and scattered Cu etching step. It is desirable to carry out (e) a de-smearing treatment after the molten and scattered Cu etching.