| abstract |
(57) [Problem] To provide a highly reliable electrical connection by reliably and directly joining conductors even when a joining surface is polished and flattened by a CMP method and solid-phase joined. And a method for producing the same. SOLUTION: Through polishing by a CMP method, a through-hole conductor 5 made of copper and a ground wiring layer 10 have a lower hardness than a through-hole insulator 11 made of silicon nitride, so that they are recessed in a dish shape and become lower. Dishing unit 1 7 results. The through-hole insulator 11 is selectively etched by the reactive ion etching method until the through-hole insulator 11 reaches the height of the bottom 19 of the dishing portion 17 of the through-hole conductor 5. The through-hole conductors 5, 25 are aligned with each other, and the bonding surfaces 12, 22 are solid-phase bonded. |