| 摘要 |
PROBLEM TO BE SOLVED: To provide a reliable wiring board which can suppress the increase in resistance values of via conductors and the occurrence of cracks around the via conductors, when the wiring board has a plurality of via conductors with different diameters. SOLUTION: A wiring board 1 includes an insulating substrate 2 which is made of ceramics and via conductors 3 which are provided on the insulating substrate 2. Each via conductor 3 is a tapered shape whose diameter differs at both ends and has an insulating component 5 contained in ceramics, and the larger the diameter in the via conductor 3 becomes, the higher the mass ratio of the insulating component 5 in the via conductor 3 becomes. A required low resistance value can be satisfied in the small diameter side of the via conductor 3, and the occurrence of cracks around the via conductor 3 can be suppressed in the large diameter side of the via conductors 3, so that high reliability can be achieved. COPYRIGHT: (C)2011,JPO&INPIT |
