Method of manufacturing substrate and substrate
A first through hole is formed in a base, a conductive layer covering an inner wall side surface of the first through hole is formed, a columnar electric conductor having a Vickers hardness of a value in a range of 30 Hv or more and 400 Hv or less is inserted into the first through hole formed with the conductive layer, pressure is applied in a vertical direction to the columnar electric conductor, and a second through hole is formed in the columnar electric conductor.
1. A substrate comprising:
a base including a first hole penetrating the base;
a first conductive layer covering an inner wall side surface of the first hole; and
a second conductive layer covering a side surface of the first conductive layer and including a second hole,
wherein the second conductive layer is different in crystalline structure from the first conductive layer and has a Vickers hardness of a value of 30 Hv or more.
2. The substrate according to claim 1 , wherein the second conductive layer is in close contact with the first conductive layer.
3. The substrate according to claim 1 , wherein the second conductive layer is made of a same conductive material as a conductive material of the first conductive layer and has a crystal grain larger than a crystal grain of the first conductive layer.
4. The substrate according to claim 1 , wherein the second conductive layer is made of a conductive material different from a conductive material of the first conductive layer.
5. The substrate according to claim 1 , wherein the second conductive layer has a Vickers hardness of a value of 400 Hv or less.
6. The substrate according to claim 1 , wherein:
the second hole is in a circular shape; and
the first hole is in a shape different from the shape of the second hole.
7. The substrate according to claim 6 , wherein the second conductive layer includes a plurality of the second holes.
8. The substrate according to claim 1 , further comprising:
a terminal inserted into and fixed to the second hole.
9. The substrate according to claim 8 , wherein the terminal is a press-fit pin or a screw.
10. The substrate according to claim 8 , wherein the second conductive layer has a thread groove formed on a side surface in the second hole.
11. A method of manufacturing a substrate, the method comprising:
forming a first hole, the first hole penetrating a base;
forming a conductive layer, the conductive layer covering an inner wall side surface of the first hole;
inserting a columnar electric conductor into the first hole formed with the conductive layer;
applying pressure in a vertical direction to the columnar electric conductor; and
forming a second hole in the columnar electric conductor.
12. The method of manufacturing a substrate according to claim 11 , wherein the columnar electric conductor is made of a same conductive material as a conductive material of the conductive layer or a conductive material different from the conductive material of the conductive layer.
13. The method of manufacturing a substrate according to claim 11 , wherein the columnar electric conductor has a side surface brought into close contact with the conductive layer.
14. The method of manufacturing a substrate according to claim 11 , wherein the columnar electric conductor has a diameter smaller than a diameter of the first hole via the conductive layer, and has a length larger than a thickness of the base.
15. The method of manufacturing a substrate according to claim 11 , wherein the columnar electric conductor has a Vickers hardness of a value of 30 Hv or more and a value of 400 Hv or less.
16. The method of manufacturing a substrate according to claim 11 , wherein the second hole is a hole penetrating the columnar electric conductor.
17. The method of manufacturing a substrate according to claim 11 , wherein the second hole is a hole not penetrating the columnar electric conductor.
18. The method of manufacturing a substrate according to claim 11 , wherein:
the second hole is in a circular shape; and
the first hole is in a shape different from the shape of the second hole.
19. The method of manufacturing a substrate according to claim 18 , wherein the columnar electric conductor includes a plurality of the second holes.
20. The method of manufacturing a substrate according to claim 11 , further comprising:
forming a thread groove on an inner wall side surface of the second hole.