| 摘要 |
PROBLEM TO BE SOLVED: To form a substrate flat and suppress the appearance of delamination of an interlayer insulating film, by forming the surfaces of via holes connected to a conductor pattern flat and forming dents in the surfaces of via holes formed in a plane layer. SOLUTION: On the upper face of a core substrate 30 of a multilayer printed wiring board 10, an inner layer copper pattern 34 which will become a ground layer is formed. As conductor layers in upper layers of an interlayer resin insulating layer 40, a conductor pattern 52 which constitutes a signal line, via holes 50B connected to the conductor pattern 52, a plan layer 53, and via holes 50A formed in the plan layer 53 are formed. The via holes 50A, 50B pass through the interlayer resin insulating layer 40 to be connected to the inner layer copper pattern 34 in a lower layer. In this case, the surfaces of the via holes 50B connected to the conductor pattern 52 are formed flat and dents 50a are formed in the surfaces of the via holes 50A formed in the plane layer 53. |
