The invention claimed is:
1. A structure with an electroconductive pattern comprising a substrate, and a copper-containing electroconductive layer disposed on the surface of the substrate,
wherein, when the main surface of the electroconductive layer on the opposite side from the substrate is defined as the first main surface and the main surface on the opposite side from the first main surface is defined as the second main surface, the electroconductive layer has a porosity of 0.01 vol % to 50 vol % in the first main surface-side region that extends from the first main surface to a depth of 100 nm in the thickness direction of the electroconductive layer, and has a porosity of 10 vol % or lower in the second main surface-side region that extends from the second main surface to a depth of 100 nm in the thickness direction of the electroconductive layer, and
wherein the element ratio of oxygen atoms to copper atoms in the first main surface-side region is greater than the element ratio of oxygen atoms to copper atoms in the second main surface-side region.
2. The structure with an electroconductive pattern according to claim 1 , wherein the porosity in the first main surface-side region is greater than the porosity in the second main surface-side region.
3. The structure with an electroconductive pattern according to claim 1 , wherein the element ratio of oxygen atoms to copper atoms in the first main surface-side region is greater than 0.025.
4. The structure with an electroconductive pattern according to claim 1 , wherein the second main surface includes nickel and/or gold.
5. The structure with an electroconductive pattern according to claim 1 , wherein part of the electroconductive layer is covered with a resin.
6. The structure with an electroconductive pattern according to claim 1 , which further comprises a solder layer situated on part of the surface of the electroconductive layer.
7. The structure with an electroconductive pattern according to claim 1 , wherein the electroconductive layer is an antenna.
8. The structure with an electroconductive pattern according to claim 1 , wherein the electroconductive layer is printed circuit board wiring.
9. A structure with an electroconductive pattern comprising a substrate, and a copper-containing electroconductive layer disposed on the surface of the substrate,
wherein, when the main surface of the electroconductive layer on the opposite side from the substrate is defined as the first main surface and the main surface on the opposite side from the first main surface is defined as the second main surface, the electroconductive layer has a porosity of 0.01 vol % to 50 vol % in the first main surface-side region that extends from the first main surface to a depth of 100 nm in the thickness direction of the electroconductive layer, and has a porosity of 10 vol % or lower in the second main surface-side region that extends from the second main surface to a depth of 100 nm in the thickness direction of the electroconductive layer, and wherein the element ratio of oxygen atoms to copper atoms in the first main surface-side region is greater than 0.025.
10. The structure with an electroconductive pattern according to claim 9 , wherein the porosity in the first main surface-side region is greater than the porosity in the second main surface-side region.
11. The structure with an electroconductive pattern according to claim 9 , wherein the second main surface includes nickel and/or gold.
12. The structure with an electroconductive pattern according to claim 9 , wherein part of the electroconductive layer is covered with a resin.
13. The structure with an electroconductive pattern according to claim 9 , which further comprises a solder layer situated on part of the surface of the electroconductive layer.
14. The structure with an electroconductive pattern according to claim 9 , wherein the electroconductive layer is an antenna.
15. The structure with an electroconductive pattern according to claim 9 , wherein the electroconductive layer is printed circuit board wiring.