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:
Aug. 04, 1998
Filed:
Jan. 16, 1996
Vernon L Brown, Barrington, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A masking method employing a photodefinable resin as a permanent dielectric mask, in which the resin contains a catalytic filler that when activated enables direct electroless plating of the resin. The resin serves to simplify selective electroplating of isolated surface features such as metal pads, while also improving the topology of the external surface of the circuit board, particularly when small metal pads require a controlled volume of a reflowable metal. The resin is preferably photodefined to eliminate recessed areas around the metal pads, thereby promoting definition of the metal features, and yielding a nearly planar surface. Additional features that can be provided with the method include external conductive ground planes and electromagnetic shield layers within a multilayer circuit board. The masking method can be advantageously used with both reflowable metals and metal alloys, such as tin/lead, and nonreflowable metals and metal alloys, such as gold, palladium and platinum.