Multilayer ceramic substrate useful for electronic circuits - comprising alternate ceramic and conductive layers and prepd. by firing assembled layers

摘要

(A) A ceramic multilayer substrate has (i) alternate ceramic and internal conductive layers, the conductive layers having a m.pt. higher than the lowest firing temp. of the ceramic layers and the uppermost layer being a ceramic layer; (ii) an insulating layer which is formed on the top ceramic layer and which has a firingt temp. lower than the lowest firing temp. of the ceramic layers; and (iii) a conductive layer which is formed on the insulating layer and which is electrically connected to the internal conductive layers. (B) Prodn. of the substrate comprises assembling and firing the alternate layer stack, applying and firing the insulating layer and then applying the conductive layer. USE/ADVANTAGE - The substrate is useful as an electronic circuit substrate. Any defects (e.g. pinholes), formed in the top ceramic layer during firing, are filled or buried by the insulating layer so that the external conductive layer and the internal conductive layers are completely insulated.