- Document Number:
20230091494
- Appl. No:
17/850045
- Application Filed:
June 27, 2022
- نبذة مختصرة :
A solar cell structure is disclosed that includes a first metal layer, formed over predefined portions of a sun-exposed major surface of a semiconductor structure, that form electrical gridlines of the solar cell; a network of carbon nanotubes formed over the first metal layer; and a second metal layer formed onto the network of carbon nanotubes, wherein the second metal layer infiltrates the network of carbon nanotubes to connect with the first metal layer to form a first metal matrix composite comprising a metal matrix and a carbon nanotube reinforcement, wherein the second metal layer is an electrically conductive layer in which the carbon nanotube reinforcement is embedded in and bonded to the metal matrix, and the first metal matrix composite provides enhanced mechanical support as well as enhanced or equal electrical conductivity for the electrical contacts against applied mechanical stressors to the electrical contacts.
- Assignees:
UNM RAINFOREST INNOVATIONS (Albuquerque, NM, US)
- Claim:
1. A solar cell structure comprising: a first metal layer, formed over predefined portions of a sun-exposed major surface of a semiconductor structure, that forms electrical gridlines of the solar cell; a network of carbon nanotubes formed over the first metal layer; and a second metal layer formed onto the network of carbon nanotubes, wherein the second metal layer infiltrates the network of carbon nanotubes to connect with the first metal layer to form a first metal matrix composite comprising a metal matrix and a carbon nanotube reinforcement, wherein the second metal layer is an electrically conductive layer in which the carbon nanotube reinforcement is embedded in and bonded to the metal matrix, and the first metal matrix composite provides enhanced mechanical support as well as enhanced or equal electrical conductivity for the electrical contacts against applied mechanical stressors to the electrical contacts.
- Claim:
2. The solar cell structure of claim 1, further comprising a back contact, wherein the back contact comprises a carbon nanotube metal matrix composite.
- Claim:
3. The solar cell structure of claim 1, wherein at least the first metal layer or the second metal layer comprises silver, copper, gold, or aluminum.
- Claim:
4. The solar cell structure of claim 1, wherein the first metal layer incorporates an adhesion layer that promotes adhesion of the first metal of the first metal layer to the semiconductor structure or materials that inhibit diffusion of a carbon nanotube metal matrix composite into the semiconductor structure.
- Claim:
5. The solar cell structure of claim 1, wherein the network of carbon nanotubes is deposited by electrodeposition, nanospreading, drop casting, or spray coating.
- Claim:
6. The solar cell structure of claim 1, wherein the network of carbon nanotubes is chemically functionalized with a carboxylic acid or an amine group prior to deposition to increase adhesion strength to surrounding metal matrix and achieve efficient metal-nanotube stress transfer.
- Claim:
7. The solar cell structure of claim 1, wherein the solar cell is an inverted metamorphic multijunction solar cell.
- Claim:
8. The solar cell structure of claim 1, further comprising a second metal matrix composite formed over the first metal matrix composite.
- Claim:
9. The solar cell structure of claim 1, wherein the semiconductor structure incorporates a silicon, germanium, or III-V compound semiconductor substrate.
- Claim:
10. The solar cell structure of claim 1, wherein the first metal layer is formed with a cathodic current density of about 2-mA/cm2 to about 10-mA/cm2 and with silver ion concentration, pH, and bath temperature held constant.
- Claim:
11. The solar cell structure of claim 1, wherein the network of carbon nanotubes comprises a plurality of multiwalled carbon nanotubes, single-walled nanotubes, or a mixture of both multiwalled and single-walled nanotubes.
- Claim:
12. The solar cell structure of claim 1, further comprising a silver seeding layer formed on a top layer of the semiconductor structure.
- Claim:
13. The solar cell structure of claim 1, wherein the network of carbon nanotubes is chemically functionalized with the carboxylic acid using an acid treatment in a 1:3 HNO3:H2SO4 mixture to produce a negative surface charge.
- Claim:
14. The solar cell structure of claim 6, wherein the amine group comprises NH2 to produce a positive surface charge by sonicating the carbon nanotube layer in a 2.8 M NH4Cl aqueous solution.
- Claim:
15. The solar cell structure of claim 6, wherein the first metal layer is about 3 μm in thickness and wherein the network of carbon nanotubes that is chemically functionalized for at about −0.5 mA/cm2 for about 15 minutes.
- Claim:
16. The solar cell structure of claim 1, wherein the network of carbon nanotubes covers an area of a top surface of the first metal layer, ranging from 12% to 86% of the metal top surface.
- Claim:
17. The solar cell structure of claim 1, further comprising a third metal layer formed between a top surface of the semiconductor structure and the first metal layer, wherein the third metal layer comprises titanium or chromium.
- Claim:
18. The solar cell of claim 17, wherein the third metal layer provides for adhesion between the top surface and the first metal layer.
- Claim:
19. The solar cell of claim 4, wherein the adhesion layer comprises chromium or titanium.
- Claim:
20. A solar module comprising: a plurality of photovoltaic (PV) cells; and one or more gridlines and one or more busbars arranged between the plurality of PV cells, wherein the one or more gridlines and the one or more busbars comprise surface-functionalized carbon nanotubes that are combined with silver to form a metal matrix composite.
- Claim:
21. The solar module of claim 20, wherein the metal matrix composite comprises: a first metal layer, formed over predefined portions of a sun-exposed major surface of a semiconductor structure, that form electrical contacts for gridlines of the solar cell; a network of carbon nanotubes formed over the first metal layer; and a second metal layer formed onto the network of carbon nanotubes, wherein the second metal layer infiltrates the network of carbon nanotubes to connect with the first metal layer to form a first metal matrix composite comprising a metal matrix and a carbon nanotube reinforcement, wherein the second metal layer is an electrically conductive layer in which the carbon nanotube reinforcement is embedded in and bonded to the metal matrix, and the first metal matrix composite provides enhanced mechanical support as well as enhanced or equal electrical conductivity for the electrical contacts against applied mechanical stressors to the electrical contacts.
- Claim:
22. The solar module of claim 21, wherein the one or more gridlines and the one or more busbars provide enhanced fracture toughness as well as electrical gap-bridging of cracked solar cells that regain electrical continuity after strain-induced failure.
- Current International Class:
01; 01; 01; 01
- الرقم المعرف:
edspap.20230091494
Processing Request
No Comments.