LASER ASSISTED METALLIZATION PROCESS FOR SOLAR CELL CIRCUIT FORMATION

• US 20190312166A1
• Filed: 04/05/2019
• Published: 10/10/2019
• Est. Priority Date: 04/06/2018
• Status: Active Grant

• Current Assignee: Maxeon Solar Pte Limited
• Original Assignee: Sunpower Corporation (Totalenergies Se)
• Inventors: Lu, Pei Hsuan, Hsia, Benjamin I., Barkhouse, David Aaron Randolph, Okawa, David C., Kavulak, David F., Abra, Lewis C., Correos, George G., Sewell, Richard Hamilton, Reagan, Ryan, Lance, Tamir, Nguyen, Thierry
• Granted Patent: US 11,646,387 B2
• Time in Patent Office: Days
• CPC Class Codes: H01L 31/022425 for solar cells
• CPC Class Codes: H01L 31/022441 Electrode arrangements specially adapted for back-contact solar cells
• CPC Class Codes: H01L 31/02245 for metallisation wrap-through [MWT] type solar cells
• CPC Class Codes: H01L 31/0516 specially adapted for interconnection of back-contact solar cells
• CPC Class Codes: H01L 31/0682 back-junction, i.e. rearside emitter, solar cells, e.g. interdigitated base-emitter regions back-junction cells
• CPC Class Codes: H01L 31/182 Special manufacturing methods for polycrystalline Si, e.g. Si ribbon, poly Si ingots, thin films of polycrystalline Si
• CPC Class Codes: H02S 40/34 comprising specially adapted electrical connection means to be structurally associated with the PV module, e.g. junction boxes
• CPC Class Codes: Y02E 10/546 Polycrystalline silicon PV cells
• CPC Class Codes: Y02E 10/547 Monocrystalline silicon PV cells

Abstract

A method of fabricating solar cell, solar laminate and/or solar module string is provided. The method may include: locating a metal foil over a plurality of semiconductor substrates; exposing the metal foil to laser beam over selected portions of the plurality of semiconductor substrates, wherein exposing the metal foil to the laser beam forms a plurality conductive contact structures having of locally deposited metal portion electrically connecting the metal foil to the semiconductor substrates at the selected portions; and selectively removing portions of the metal foil, wherein remaining portions of the metal foil extend between at least two of the plurality of semiconductor substrates.

Claims

1. A method of fabricating solar cell string, comprising:

locating a metal foil over a plurality of semiconductor substrates;

exposing the metal foil to laser beam over selected portions of the plurality of semiconductor substrates to form a plurality conductive contact structures having of locally deposited metal portion electrically connecting the metal foil to the semiconductor substrates at the selected portions; and

selectively removing portions of the metal foil, wherein remaining portions of the metal foil extend between at least two of the plurality of semiconductor substrates.

2. The method of claim 1, wherein the metal foil comprises a continuous sheet.

3. The method of claim 1, wherein the semiconductor substrates each comprise N-type and P-type semiconductor regions.

4. The method of claim 1, further comprising, forming a plurality of N-type and P-type semiconductor regions in or above the substrate.

5. The method of claim 1, further comprising;

electrically connecting one or more junction boxes to the metal foil and/or diodes to the metal foil.

6. The method of claim 1, wherein at least a portion of the solar cells are arranged as a parallel circuit, series circuit, or a combination thereof.

7. The method of claim 3, further comprising:

exposing the metal foil to a laser beam in locations over N-type and P-type semiconductor regions to form a plurality of conductive contact structures electrically connected to the plurality of N-type and P-type semiconductor regions, each conductive contact structure comprising a locally deposited metal portion.

8. The method of claim 1, wherein the metal foil is a first metal foil, the method further comprising:

locating a second metal source over the first metal foil; and

bonding the second metal foil over selected portions of the first metal foil to electrically connect the second metal foil to the first metal foil at the selected portions.

9. A solar cell string, comprising:

a plurality of semiconductor substrates;

a metal foil located on and extending between a first semiconductor substrate and a second semiconductor substrate, wherein the metal foil is disposed over a first side of the first semiconductor substrate;

one or more conductive contact structures including locally deposited metal portions electrically connecting the metal foil to the first semiconductor substrate; and

one or more conductive contact structures including an a locally deposited metal portions electrically connecting the metal foil to a first side of second semiconductor substrate.

10. The solar cell string of claim 9, further comprising, one or more junction boxes electrically connected to the metal foil and/or bypass diodes electrically connected to the metal foil.

11. The solar cell string of claim 9, wherein at least a portion of the solar cells are arranged in parallel or in series.

12. The solar cell string of claim 9, wherein at least a portion of the plurality of semiconductor substrates are arranged as a string of solar cells.

13. The solar cell string of claim 9, wherein at least a portion of the plurality of semiconductor substrates are arranged as an array of solar cell strings.

14. The solar cell string of claim 13, wherein the semiconductor substrates each comprise N-type and P-type semiconductor regions.

15. The solar cell string of claim 14, further comprising a plurality of conductive contact structures electrically connected to the plurality of N-type and P-type semiconductor regions, each conductive contact structure comprising a locally deposited metal portion disposed in direct contact with a corresponding one of the N-type and P-type semiconductor regions.

16. A method of fabricating solar laminate, comprising:

locating a metal foil over a plurality of semiconductor substrates;

exposing the metal foil to laser beam over selected portions of the plurality of semiconductor substrates to form a plurality conductive contact structures having of locally deposited metal portion electrically connecting the metal foil to the semiconductor substrates at the selected portions;

selectively removing portions of the metal foil, wherein remaining portions of the metal foil extend between at least two of the plurality of semiconductor substrates;

placing an encapsulant over the semiconductor substrates; and

performing a thermal process to form the solar laminate.

17. The method of claim 16, wherein the metal foil comprises a continuous sheet.

18. The method of claim 16, wherein the semiconductor substrates each comprise solar cells.

19. The method of claim 16, wherein the metal foil comprises a continuous sheet.

20. The method of claim 16, wherein the semiconductor substrates each comprise N-type and P-type semiconductor regions.