| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a multi-layer ceramic substrate having a conductive via of a double-layer structure which can prevent losses of electric conductivity and a signal. <P>SOLUTION: The substrate has a plurality of dielectric layers, and has the circuit pattern comprising at least one or more conductive vias formed in at least several dielectric layers of the plurality of dielectric layers and conductive patterns. The at least one of the conductive vias has the outer peripheral portion formed along the via-hole inner wall piercing the dielectric layers and formed of a first conductive substance containing metal and has an inner-core portion formed so as to be filled in the outer peripheral portion and formed of a second conductive substance having a higher contraction starting temperature than that of the first conductive substance. By this conductive via, the AC electric resistance of the conductive via can be reduced to a level of a pure Ag in a microwave band and the signal loss of the conductive via can be prevented in the microwave (mm wave) band. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
