Solar cells with differentiated P-type and N-type region architectures

Patent metadata

Field	Value
Publication number	US-11594648-B2
Application number	US-202016853437-A
Country	US
Kind code	B2
Filing date	Apr 20, 2020
Priority date	Sep 30, 2016
Publication date	Feb 28, 2023
Grant date	Feb 28, 2023

Abstract

Methods of fabricating solar cell emitter regions with differentiated P-type and N-type regions architectures, and resulting solar cells, are described. In an example, a solar cell can include a substrate having a light-receiving surface and a back surface. A first doped region of a first conductivity type, wherein the first doped region is disposed in a first portion of the back surface. A first thin dielectric layer disposed over the back surface of the substrate, where a portion of the first thin dielectric layer is disposed over the first doped region of the first conductivity type. A first semiconductor layer disposed over the first thin dielectric layer. A second doped region of a second conductivity type in the first semiconductor layer, where the second doped region is disposed over a second portion of the back surface. A first conductive contact disposed over the first doped region and a second conductive contact disposed over the second doped region.

First claim

What is claimed is:

1. A solar cell comprising:
a substrate having a light-receiving surface and a back surface, wherein the substrate comprises a first portion and a second portion at the back surface of the substrate, and the first portion includes a first doped region of a first conductivity type;
a dopant region disposed over the first doped region;
a first thin dielectric layer disposed over the back surface of the substrate, wherein a first portion of the first thin dielectric layer is disposed over the dopant region and the first doped region of the first conductivity type, and wherein a second portion of the first thin dielectric layer is disposed on the second portion of the substrate;
a first semiconductor layer disposed on the first thin dielectric layer, wherein a first portion of the first semiconductor layer is disposed over the first portion of the first thin dielectric layer, and wherein a second portion of the first semiconductor layer is a second doped region of a second conductivity type that is disposed over the second portion of the first thin dielectric layer, such that the first doped region is formed in the first portion of the substrate at the back surface and the second doped region is formed over the second portion of the back surface of the substrate, wherein the second doped region is not laterally overlapping with the first doped region;
a first conductive contact disposed over the first doped region; and
a second conductive contact disposed over the second doped region.

2. The solar cell of claim 1 , wherein the substrate comprises a monocrystalline silicon substrate.

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

4. The solar cell of claim 1 , wherein the first thin dielectric layer comprises a tunnel oxide.

5. The solar cell of claim 1 , further comprising a contact opening disposed between the first doped region and the first conductive contact, wherein the contact opening allows for an electrical connection between the first doped region and the first conductive contact.

6. The solar cell of claim 1 , wherein the first semiconductor layer comprises polysilicon.

7. The solar cell of claim 1 , further comprising a second semiconductor layer disposed on the light-receiving surface.

8. The solar cell of claim 7 , wherein the second semiconductor layer comprises polysilicon.

9. A solar cell comprising:
a substrate having a light-receiving surface and a back surface, wherein the substrate comprises a first portion and a second portion at the back surface of the substrate and the first portion includes a first doped region of a first conductivity type;
a dopant region disposed over the first doped region;
a first thin dielectric layer disposed over the back surface of the substrate, wherein a first portion of the first thin dielectric layer is disposed over the dopant region and the first doped region of the first conductivity type, and wherein a second portion of the first thin dielectric layer is disposed on the second portion of the substrate;
a first semiconductor layer disposed over the first thin dielectric layer, the first semiconductor layer comprising a first portion and a second portion, and the first portion of the first semiconductor layer disposed over the first portion of the first thin dielectric layer, wherein a second portion of the first semiconductor layer is a second doped region of a second conductivity type that is disposed over the second portion of the of the first thin dielectric layer and that is separate from the first portion of the first semiconductor layer, such that the first doped region is formed in the first portion of the substrate at the back surface and the second doped region is formed over the second portion of the back surface of the substrate, wherein the second doped region is not laterally overlapping with the first doped region;
a first conductive contact disposed over the first doped region; and
a second conductive contact disposed over the second doped region.

10. The solar cell of claim 9 , wherein the substrate comprises a monocrystalline silicon substrate.

11. The solar cell of claim 9 , wherein the first conductivity type is P-type and the second conductivity type is N-type.

12. The solar cell of claim 9 , wherein the first thin dielectric layer comprises a tunnel oxide.

13. The solar cell of claim 9 , further comprising a contact opening disposed between the first doped region and the first conductive contact, wherein the contact opening allows for an electrical connection between the first doped region and the first conductive contact.

14. The solar cell of claim 9 , wherein the first semiconductor layer comprises polysilicon.

15. The solar cell of claim 9 , further comprising a second semiconductor layer disposed on the light-receiving surface.

16. The solar cell of claim 15 , wherein the second semiconductor layer comprises polysilicon.

17. The solar cell of claim 1 , wherein a bottommost surface of the second doped region is vertically spaced apart from an uppermost surface of the first doped region.

18. The solar cell of claim 9 , wherein a bottommost surface of the second doped region is vertically spaced apart from an uppermost surface of the first doped region.

Assignees

• Sunpower Corp

Inventors

• Rim Seung Bum
• Johnson Michael C

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

• H10F77/164

  Polycrystalline semiconductors · CPC title

• H10F77/707

  of the substrates or of layers on substrates, e.g. textured ITO layer on a glass substrate · CPC title

• H10F10/16 Primary

  Photovoltaic cells having only PN heterojunction potential barriers · CPC title

• H10F77/703

  of the semiconductor bodies, e.g. textured active layers · CPC title