配线基板及其制造方法;WIRING SUBSTRATE AND MANUFACTURING METHOD THEREOF

摘要

本发明之配线基板10系具备：下层之配线导体1；上层之绝缘层2，积层在下层之配线导体1上，且具有以下层之配线导体1为底面之介层孔5；及介层导体3，连接在下层之配线导体1且填充于介层孔5内；其中，上层之绝缘层2系具有依序积层在下层之配线导体1上的第1树脂层2a、及第2树脂层2b，介层孔5系在第1树脂层2a与第2树脂层2b之交界，具有介层孔5之内壁遍及全周地凹入之环状之沟槽部5a，且介层导体3系以咬入沟槽部5a内之方式被填充。; an upper layer insulating layer 2 laminated on the lower layer wiring conductor 1 and having a via hole 5 having a bottom surface on the lower layer wiring conductor 1; and a via conductor 3 connected to the lower layer wiring conductor 1 and filled into the via hole 5; wherein the lower layer insulating layer 2 has a first resin layer 2a and a second resin layer 2b sequentially laminated on the lower layer wiring conductor 1, the via hole 5 has an annular trench portion 5a concaving in an inner periphery of an interior wall of the via hole 5 at the boundary between the first resin layer 2a and the second resin layer 2b, and the via conductor 3 is filled to bite into the trench portion 5a.