Wiring board and method of manufacturing the same
OwnerTakaaki KATO, Naoki TAKATAinventors
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Abstract
A wiring board includes a ceramic substrate having an upper surface and a lower surface and a conductor pattern formed on the upper surface of the ceramic substrate. The conductor pattern includes a base metal layer formed on the upper surface of the ceramic substrate and a metal layer formed on the upper surface of the ceramic substrate so as to entirely cover the base metal layer. The base metal layer contains at least one of titanium and chromium in addition to copper and silver. The metal layer contains copper as a main component, and a weight percentage of silver contained in the metal layer is smaller than a weight percentage of silver contained in the base metal layer. Side surfaces of the base metal layer are covered with the metal layer.
Claims16
A wiring board comprising:
- a ceramic substrate having a first surface and a second surface on an opposite side of the first surface;
- and
- a first conductor pattern formed on the first surface of the ceramic substrate,
- wherein the first conductor pattern includes:
- a first base metal layer formed on the first surface of the ceramic substrate;
- and
- a first metal layer formed on the first surface of the ceramic substrate so as to entirely cover the first base metal layer,
- wherein the first base metal layer contains at least one of titanium and chromium in addition to copper and silver,
- wherein the first metal layer contains copper as a main component and a weight percentage of silver contained in the first metal layer is smaller than a weight percentage of the silver contained in the first base metal layer, and
- wherein side surfaces of the first base metal layer are covered with the first metal layer.
A method of manufacturing a wiring board comprising:
- (a) preparing a ceramic substrate having a first surface and a second surface on an opposite side of the first surface;
- (b) applying a first base metal paste onto the first surface of the ceramic substrate;
- (c) forming a first base metal layer by firing the first base metal paste;
- (d) after the (c), applying a first metal paste so as to entirely cover the first base metal layer;
- and
- (e) after the (d), forming a first metal layer by firing the first metal paste,
- wherein the first base metal paste contains at least one of titanium particles and chromium particles in addition to copper particles and silver particles,
- wherein a weight percentage of copper particles contained in the first metal paste is larger than a weight percentage of the copper particles contained in the first base metal paste, and a weight percentage of silver particles contained in the first metal paste is smaller than a weight percentage of the silver particles contained in the first base metal paste, and
- wherein, in the (d), side surfaces of the first base metal layer are covered with the first metal paste.
Dependencies are inferred from the claim text.