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. 24, 2015
Filed:
Nov. 15, 2013
International Business Machines Corporation, Armonk, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An integrated circuit substrate is designed and fabricated with a selectively applied transmission line reference plane metal layer to achieve signal path shielding and isolation, while avoiding drops in impedance due to capacitance between large diameter vias and the transmission line reference plane metal layer. The transmission line reference plane defines voids above (or below) the signal-bearing plated-through holes (PTHs) that pass through a rigid substrate core, so that the signals are not degraded by an impedance mismatch that would otherwise be caused by shunt capacitance from the top (or bottom) of the signal-bearing PTHs to the transmission line reference plane. For voltage-plane bearing PTHs, no voids are introduced, so that signal path conductors can be routed above or adjacent to the voltage-plane bearing PTHs, with the transmission line reference plane preventing shunt capacitance between the signal path conductors and the PTHs.