Solderable contact regions
View Patent ↗A contact region for a semiconductor substrate is disclosed. Embodiments can include forming a seed metal layer having an exposed solder pad region on the semiconductor substrate and forming a first metal layer on the seed metal layer. In an embodiment, a solderable material, such as silver, can be formed on the exposed solder pad region prior to forming the first metal layer. Embodiments can include forming a solderable material on the exposed solder pad region after forming the first metal layer. Embodiments can also include forming a plating contact region on the seed metal layer, where the plating contact region allows for electrical conduction during a plating process.
1. A solar cell, comprising:
a seed metal layer formed on a surface of the solar cell and at least partially laterally surrounding a solderable material, the solderable material formed directly on a first solder pad region on the surface of the solar cell; and
a first metal layer formed directly on the seed metal layer and directly on the solderable material.
2. The solar cell of claim 1 , wherein the seed metal layer is a material selected from the group consisting of aluminum paste, a layer of aluminum, aluminum micro-particles and aluminum nano-particles.
3. The solar cell of claim 1 , wherein the solderable material comprises silver or a layer of silver.
4. The solar cell of claim 1 , wherein the solderable material has a thickness in the range of 1-10 microns.
5. The solar cell of claim 1 , wherein the first metal layer is a metal selected from the group consisting of nickel, gold, silver, rhodium, chromium, zinc, tin and cadmium.
6. The solar cell of claim 1 , wherein the solder pad region has a shape selected from the group consisting of a rectangular shape, circular shape, oblong shape, square shape, triangular shape, trapezoid shape and polygon shape.
7. The solar cell of claim 1 , further comprising the solderable material formed on a second solder pad region.
8. A solar cell, comprising:
a patterned seed metal layer on a surface of the solar cell, wherein the patterned seed metal layer terminates at a solder pad region on the surface of the solar cell;
a first metal layer formed directly on the patterned seed metal layer; and
a solderable material formed directly on the solder pad region on the surface of the solar cell,
wherein the seed metal layer laterally surrounds the solderable material and the first metal layer is directly on the solderable material.
9. The solar cell of claim 8 , wherein the seed metal layer is a material selected from the group consisting of aluminum paste, a layer of aluminum, aluminum micro-particles and aluminum nano-particles.
10. The solar cell of claim 8 , wherein the solderable material comprises silver or a layer of silver.
11. The solar cell of claim 8 , wherein the solderable material has a thickness in the range of 1-10 microns.
12. The solar cell of claim 8 , wherein the first metal layer is a metal selected from the group consisting of nickel, gold, silver, rhodium, chromium, zinc, tin and cadmium.
13. The solar cell of claim 8 , further comprising the solderable material formed on a second solder pad region.
14. A solar cell, comprising:
a seed metal layer on a surface of the solar cell, the seed metal layer having a plating contact region and at least partially laterally surrounding a solderable material, the solderable material formed directly on a first solder pad region on the surface of the solar cell; and
a first metal layer formed directly on the seed metal layer and directly on the solderable material.
15. The solar cell of claim 14 , wherein the seed metal layer is a material selected from the group consisting of aluminum paste, a layer of aluminum, aluminum micro-particles and aluminum nano-particles.
16. The solar cell of claim 14 , wherein the solderable material comprises silver or a layer of silver.
17. The solar cell of claim 14 , wherein the solderable material has a thickness in the range of 1-10 microns.
18. The solar cell of claim 14 , wherein the first metal layer is a material selected from the group consisting of nickel, gold, silver, rhodium, chromium, zinc, tin and cadmium.
19. The solar cell of claim 14 , wherein the first solder pad region has a shape selected from the group consisting of a rectangular shape, circular shape, oblong shape, square shape, triangular shape, trapezoid shape and polygon shape.
20. The solar cell of claim 14 , further comprising the solderable material formed on a second solder pad region.