| 摘要 |
A substrate includes a first insulating layer provided on a base board, a second insulating layer provided on the first insulating layer, a third insulating layer provided on the second insulating layer, a pad electrode provided on the third insulating layer, and a hole formed to penetrate the substrate and reaching the pad electrode. A diameter of the hole in the first insulating layer is larger than a diameter of the hole in the second insulating layer, and the first insulating layer and the second insulating layer are formed using different materials from each other and the second insulating layer and the third insulating layer are formed using different materials from each other. |
