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. 01, 2000
Filed:
Mar. 12, 1998
Abstract
The invention related to a paste for via hole filling which enables inner via hole connection between electrode layers without employing through hole plating techniques, and a multi-layered printed circuit board using the same. The conductive paste composition of the invention comprises a) 70-90 wt % of copper particles of an average particle size of 0.5-8 .mu.m; b) 0.5-15 wt % of insulating particles of an average particle size of 8-20 .mu.m; and, c) 6-17 wt % of heat setting type liquid epoxy resin, in order to exhibit low viscosity and low volatility. The conductive paste is printed and filled into through holes passing through a laminated substrate which is provide with copper foils on both sides thereof, to form a printed circuit board in which the via holes are electrically connected after thermosetting. By adding insulating particles of large particle size, the amount of copper particles to be added is decreased so that a via hole connection of low specific resistance and high reliability is obtained, and improvements in a decrease of viscosity and continuous printability of the paste itself can be achieved.