Copper paste and wiring board using the same

摘要

A wiring board obtained by filling a copper paste in a via hole formed on a ceramic green sheet and firing it to form an insulating layer and a via conductor (3), the copper paste comprising a copper powder (5), an organic vehicle and at least one (7) selected from the group consisting of: a ceramic particle having an average particle size of 100 nm or less; and an Fe 2 O 3 particle, wherein the copper paste comprises from 6 to 20 parts by mass of the organic vehicle per 100 parts by mass of the copper powder.