Solar cell having an emitter region with wide bandgap semiconductor material

Patent metadata

Field	Value
Publication number	US-12009449-B2
Application number	US-202318107917-A
Country	US
Kind code	B2
Filing date	Feb 9, 2023
Priority date	Mar 23, 2012
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

Solar cells having emitter regions composed of wide bandgap semiconductor material are described. In an example, a method includes forming, in a process tool having a controlled atmosphere, a thin dielectric layer on a surface of a semiconductor substrate of the solar cell. The semiconductor substrate has a bandgap. Without removing the semiconductor substrate from the controlled atmosphere of the process tool, a semiconductor layer is formed on the thin dielectric layer. The semiconductor layer has a bandgap at least approximately 0.2 electron Volts (eV) above the bandgap of the semiconductor substrate.

First claim

What is claimed is:

1. A solar cell, comprising:
a semiconductor substrate;
a first thin dielectric layer disposed on the semiconductor substrate;
a first semiconductor region of a first conductivity type disposed on the first thin dielectric layer;
a second thin dielectric layer disposed on the semiconductor substrate; and
a second semiconductor region of a second conductivity type disposed on the second thin dielectric layer, the second conductivity type opposite the first conductivity type, wherein the second thin dielectric layer is disposed on a sidewall surface of the first semiconductor region, and the second dielectric layer laterally separates the first and second semiconductor regions.

2. The solar cell of claim 1 , wherein the first semiconductor region is a first polysilicon region, and the second semiconductor region is a second polysilicon region.

3. The solar cell of claim 1 , wherein the first thin dielectric layer is a first oxide layer, and the second thin dielectric layer is a second oxide layer.

4. The solar cell of claim 3 , wherein the first oxide layer and the second oxide layer comprise silicon.

5. The solar cell of claim 1 , wherein the second thin dielectric layer covers at least a portion of the first semiconductor region.

6. The solar cell of claim 1 , wherein the second thin dielectric layer and the second semiconductor region include a contact opening through which a metal contact is formed to contact to the first semiconductor region.

7. The solar cell of claim 1 , wherein the first conductivity type is N-type, and the second conductivity type is P-type.

8. The solar cell of claim 1 , wherein the first conductivity type is P-type, and the second conductivity type is N-type.

9. The solar cell of claim 1 , wherein the second semiconductor region has a dopant concentration approximately in the range of 1×10 17 -1×10 21 atoms/cm 3 .

10. The solar cell of claim 1 , further comprising:
an oxide layer disposed over a light receiving surface of the semiconductor substrate, the light receiving surface opposite the first thin dielectric layer and the second thin dielectric layer;
an amorphous silicon layer disposed on the oxide layer; and

an anti-reflective coating (ARC) layer disposed on the amorphous silicon layer, the ARC layer comprising silicon nitride.

11. A solar cell, comprising:
a silicon substrate;
a first dielectric layer on the silicon substrate;
a first silicon region of a first conductivity type on the first dielectric layer;
a second dielectric layer on the silicon substrate; and
a second silicon region of a second conductivity type on the second dielectric layer, the second conductivity type opposite the first conductivity type, wherein the second dielectric layer is on a sidewall surface of the first silicon region, and the second dielectric layer laterally separates the first and second silicon regions.

12. The solar cell of claim 11 , wherein the first silicon region is a first polysilicon region, and the second silicon region is a second polysilicon region.

13. The solar cell of claim 11 , wherein the first dielectric layer is a first oxide layer, and the second dielectric layer is a second oxide layer.

14. The solar cell of claim 13 , wherein the first oxide layer and the second oxide layer comprise silicon.

15. The solar cell of claim 11 , wherein the second dielectric layer covers at least a portion of the first silicon region.

16. The solar cell of claim 11 , wherein the second dielectric layer and the second silicon region include a contact opening through which a metal contact is formed to contact to the first silicon region.

17. The solar cell of claim 11 , wherein the first conductivity type is N-type, and the second conductivity type is P-type.

18. The solar cell of claim 11 , wherein the first conductivity type is P-type, and the second conductivity type is N-type.

19. The solar cell of claim 11 , wherein the second silicon region has a dopant concentration approximately in the range of 1×10 17 -1×10 21 atoms/cm 3 .

20. The solar cell of claim 11 , further comprising:
an oxide layer over a light receiving surface of the silicon substrate, the light receiving surface opposite the first dielectric layer and the second dielectric layer;
an amorphous silicon layer on the oxide layer; and
an anti-reflective coating (ARC) layer on the amorphous silicon layer, the ARC layer comprising silicon nitride.

21. A solar cell, comprising:
a semiconductor substrate;
a first thin dielectric layer disposed on the semiconductor substrate;
a first semiconductor region of a first conductivity type disposed on the first thin dielectric layer;
a second thin dielectric layer disposed on the semiconductor substrate; and
a second semiconductor region of a second conductivity type disposed on the second thin dielectric layer, the second conductivity type opposite the first conductivity type, wherein the second thin dielectric layer is disposed on a lateral surface of the first semiconductor region, and the second dielectric layer separates the first and second semiconductor regions, wherein the second semiconductor region has a dopant concentration approximately in the range of 1×10 17 -1×10 21 atoms/cm 3 .

22. A solar cell, comprising:
a semiconductor substrate;
a first thin dielectric layer disposed on the semiconductor substrate;
a first semiconductor region of a first conductivity type disposed on the first thin dielectric layer;
a second thin dielectric layer disposed on the semiconductor substrate;
a second semiconductor region of a second conductivity type disposed on the second thin dielectric layer, the second conductivity type opposite the first conductivity type, wherein the second thin dielectric layer is disposed on a lateral surface of the first semiconductor region, and the second dielectric layer separates the first and second semiconductor regions;
an oxide layer disposed over a light receiving surface of the semiconductor substrate, the light receiving surface opposite the first thin dielectric layer and the second thin dielectric layer;
an amorphous silicon layer disposed on the oxide layer; and
an anti-reflective coating (ARC) layer disposed on the amorphous silicon layer, the ARC layer comprising silicon nitride.

Assignees

• Maxeon Solar Pte Ltd

Inventors

• Swanson Richard M
• Bunea Marius M
• Johnson Michael C
• Smith David D
• Shen Yu-Chen
• Cousins Peter J
• Dennis Tim

Classifications

• H10F71/00

  Manufacture or treatment of devices covered by this subclass (patterning processes to connect thin photovoltaic cells in integrated devices, or assemblies of multiple devices, having photovoltaic cells H10F19/33; manufacture or treatment of encapsulations or containers for integrated devices, or assemblies of multiple devices, having photovoltaic cells H10F19/80; manufacture or treatment of integrated devices, or assemblies of multiple devices, comprising at least one element in which radiation controls the flow of current H10F39/00) · CPC title

• H10F10/146

  Back-junction photovoltaic cells, e.g. having interdigitated base-emitter regions on the back side · CPC title

• H10F19/00

  Integrated devices, or assemblies of multiple devices, comprising at least one photovoltaic cell covered by group H10F10/00, e.g. photovoltaic modules · CPC title

• H10F77/166

  Amorphous semiconductors · CPC title

• H10F77/164

  Polycrystalline semiconductors · CPC title