To provide a multilayer thick film substrate having external conductors with favorable soldering characteristics and anti-migration characteristics without causing irregularities on the surface.
A multilayer thick film substrate 10 has a sheet ceramic substrate 11 whose main component is alumina. On the ceramic substrate 11, there are provided with internal conductors 12 whose main component is silver, insulating glass layers 13 whose main component is glass ceramic, via hole conductors 15 whose main component is silver and nickel, piercing the insulating glass layers 13, and external conductors 16 whose main component is copper. In this multilayer thick film substrate, a conducting material containing silver and nickel is used for the via hole conductors so that, when baked in the oxide atmosphere, nickel is oxidized and expanded to make up for shrinkage of silver due to baking. Consequently, soldering characteristics and anti-migration characteristics are improved.
WADA RYUICHIRO
MORISHIMA YASUYUKI
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