Electrical contacts to nanostructured areas
A process is provided for contacting a nanostructured surface. In that process, a substrate is provided having a nanostructured material on a surface, the substrate being conductive and the nanostructured material being coated with an insulating material. A portion of the nanostructured material is at least partially removed. A conductor is deposited on the substrate in such a way that it is in electrical contact with the substrate through the area where the nanostructured material has been at least partially removed.
1. An optoelectronic device comprising:
a substrate including a first surface;
a nanostructured area including nanostructures on the first surface of the substrate, the nanostructured area including a first segment in which the nanostructures are intact and a second segment in which the nanostructures are at least partially broken or removed, the second segment being laterally displaced from the first segment in a plane defined by the first surface of the substrate;
an electrically insulating layer atop the first surface; and
a conductor atop the electrically insulating layer over the second segment.
2. The optoelectronic device of claim 1 , wherein the insulating layer comprises alumina.
3. The optoelectronic device of claim 1 , wherein the second segment comprises a grid shape.
4. The optoelectronic device of claim 1 , wherein the conductor makes electrical contact to the substrate through the insulating layer over the second segment.
5. The optoelectronic device of claim 1 , wherein the second segment comprises a plurality of holes in the insulating layer having diameters between about 25 nm and about 250 nm and exposing the substrate.
6. The optoelectronic device of claim 5 , wherein the conductor makes electrical contact to the substrate through the plurality of holes in the insulating layer.
7. The optoelectronic device of claim 5 , wherein the device is a photovoltaic cell and its power conversion efficiency for AM1.5G simulated sunlight is at least about 10%.
8. The optoelectronic device of claim 1 , further comprising a covering layer disposed atop the second segment.
9. The optoelectronic device of claim 8 , wherein the covering layer comprises aluminum.
10. The optoelectronic device of claim 8 , wherein the covering layer comprises titanium.
11. The optoelectronic device of claim 1 , wherein the nanostructures comprise silicon.
12. The optoelectronic device of claim 1 , comprising a photovoltaic cell.
13. The optoelectronic device of claim 11 , wherein the nanostructures comprise silicon nanowires.
14. An optoelectronic device comprising:
a substrate including a first surface;
a nanostructured area on the first surface of the substrate, the nanostructured area including nanostructures;
a passivation layer atop the first surface;
a first segment of the nanostructured area including a plurality of holes in the passivation layer;
a second segment of the nanostructured area being free of holes in the passivation layer, the second segment being laterally displaced from the first segment in a plane defined by the first surface of the substrate; and
a conductor atop the passivation layer over the first segment.
15. The optoelectronic device of claim 14 , further comprising a covering layer disposed atop the first segment.
16. The optoelectronic device of claim 14 , wherein the nanostructures comprise silicon.
17. The optoelectronic device of claim 16 , wherein the nanostructures comprise silicon nanowires.
18. The optoelectronic device of claim 14 , comprising a photovoltaic cell.