| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a multilayer printed wiring board in which connection reliability does not deteriorate while employing small diameter via holes. <P>SOLUTION: A via hole 60A formed on a lid plating layer 36a and having the greater part of its bottom formed in a part other than on a through hole 36 is subjected to a larger stress during a heat cycle as compared with a via hole 160 being formed in a second interlayer resin insulation layer 150. Consequently, the diameter at the bottom of the via hole 60A is made smaller than the diameter at the bottom of the via hole 160. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
