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:
Jul. 07, 2009
Filed:
Nov. 08, 2006
Jaroslaw A. Magera, Palatine, IL (US);
Gregory J. Dunn, Arlington Heights, IL (US);
Kathy D. Leganski, Elgin, IL (US);
Jaroslaw A. Magera, Palatine, IL (US);
Gregory J. Dunn, Arlington Heights, IL (US);
Kathy D. Leganski, Elgin, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
Closed vias are formed in a multilayer printed circuit board by laminating a dielectric layer to one side of a central core having a metal layer on each side. A second dielectric layer is laminated to the other side of the central core. Closed vias in the central core have been formed by drilling partially through but not completely penetrating the central core, and then completing the via from the opposite side with a hole that is much smaller in diameter to form a pathway that penetrates completely through the central core from one side to another. The via is then plated with metal to substantially close the smaller hole. Approximately one half of the closed vias are situated such that the closed aperture faces one dielectric layer and a remainder of the closed vias are situated such that the closed aperture faces the other dielectric layer. Resin from one dielectric layer fills the cavities of approximately one half of the closed vias, and resin from the other dielectric layer fills the circular cavities of the remainder of the closed vias. The total amount of resin migrated from each of the dielectric layers into the closed via cavities is approximately equal.