Solar cell, manufacturing method thereof, and photovoltaic module

1. A solar cell, comprising:

a semiconductor substrate, wherein a rear surface of the semiconductor substrate has a first texture structure, the first texture structure has a non-pyramid-shaped microstructure and includes two or more first substructures at least partially stacked on one another, a top surface of the first substructure is a polygonal plane, and a one-dimensional size of the top surface of the outermost first substructure is less than or equal to 45 μm; and wherein a front surface of the semiconductor substrate has a second texture structure, the second texture structure includes a pyramid-shaped microstructure, the pyramid-shaped microstructure includes a top portion away from the front surface of the semiconductor substrate and a bottom portion close to the front surface of the semiconductor substrate, and in a direction away from the front surface and perpendicular to the front surface, a distance between the top portion and the bottom portion of the pyramid-shaped microstructure is less than or equal to 5 μm;

a first passivation layer located on the second texture structure of the front surface of the semiconductor substrate;

a tunnel oxide layer located on the first texture structure of the rear surface of the semiconductor substrate;

a doped conductive layer located on a surface of the tunnel oxide layer; and

a second passivation layer located on a surface of the doped conductive layer.

2. The solar cell according to claim 1 , wherein for the two or more first substructures at least partially stacked on one another, in the direction away from the rear surface and perpendicular to the rear surface, a distance between the top surface of the outermost first substructure and the top surface of the adjacent first substructure is equal to or less than 2 μm.

3. The solar cell according to claim 1 , wherein a shape of the polygonal plane includes at least one of a diamond, a square, a trapezoid, a substantially diamond, a substantially square or a substantially trapezoid.

4. The solar cell according to claim 1 , wherein a thickness of the tunnel oxide layer on the top surface of the outermost first substructure is less than a thickness of the tunnel oxide layer on a side surface of the outermost first substructure.

5. The solar cell according to claim 1 , wherein the first texture structure further includes two or more adjacent second substructures that do not stacked on one another, and a one-dimensional size of a top surface of the second substructure away from the rear surface is less than or equal to 45 μm.

6. The solar cell according to claim 5 , wherein the top surface of the second substructure is a polygonal plane.

7. The solar cell according to claim 1 , wherein the tunnel oxide layer includes at least one of a silicon oxide layer, an aluminum oxide layer, a silicon oxynitride layer, a molybdenum oxide layer or a hafnium oxide layer, and the tunnel oxide layer has a thickness ranging from 0.8 nm to 2 nm.

8. The solar cell according to claim 1 , wherein the second passivation layer includes at least one of a silicon nitride layer, a silicon oxide layer or a silicon oxynitride layer, and the second passivation layer has a thickness ranging from 70 nm to 120 nm.

9. The solar cell according to claim 1 , wherein the first passivation layer includes at least one of a silicon oxide layer, a silicon nitride layer, an aluminum oxide layer or a silicon oxynitride layer.

10. The solar cell according to claim 1 , wherein the first passivation layer is a stacked passivation structure of an aluminum oxide layer and a silicon nitride layer, the aluminum oxide layer has a thickness ranging from 2 nm to 10 nm, and the silicon nitride layer has a thickness ranging from 50 nm to 110 nm.

11. The solar cell according to claim 1 , wherein the first passivation layer is a stacked passivation structure of an aluminum oxide layer, a silicon nitride layer and a silicon oxynitride layer sequentially stacked, the aluminum oxide layer has a thickness ranging from 2 nm to 10 nm, the silicon nitride layer has a thickness ranging from 40 nm to 80 nm, and the silicon oxynitride layer has a thickness ranging from 10 nm to 60 nm.

12. The solar cell according to claim 1 , wherein the semiconductor substrate is an N-type monocrystalline silicon substrate, the doped conductive layer is an N-type doped polycrystalline silicon layer, an N-type doped microcrystalline silicon layer or an N-type doped amorphous silicon layer, and the doped conductive layer has a thickness ranging from 60 nm to 200 nm.

13. A photovoltaic module, comprising a plurality of solar cell strings, wherein each of the plurality of solar cell strings comprises solar cells, and at least one of the solar cells comprises:

a semiconductor substrate, wherein a rear surface of the semiconductor substrate has a first texture structure, the first texture structure has a non-pyramid-shaped microstructure and includes two or more first substructures at least partially stacked on one another, a top surface of the first substructure is a polygonal plane, and a one-dimensional size of the top surface of the outermost first substructure is less than or equal to 45 μm; and wherein a front surface of the semiconductor substrate has a second texture structure, the second texture structure includes a pyramid-shaped microstructure, the pyramid-shaped microstructure includes a top portion away from the front surface of the semiconductor substrate and a bottom portion close to the front surface of the semiconductor substrate, and in a direction away from the front surface and perpendicular to the front surface, a distance between the top portion and the bottom portion of the pyramid-shaped microstructure is less than or equal to 5 μm;

a first passivation layer located on the second texture structure of the front surface of the semiconductor substrate;

a tunnel oxide layer located on the first texture structure of the rear surface of the semiconductor substrate;

a doped conductive layer located on a surface of the tunnel oxide layer; and

a second passivation layer located on a surface of the doped conductive layer.

14. The photovoltaic module according to claim 13 , wherein for the two or more first substructures at least partially stacked on one another, in the direction away from the rear surface and perpendicular to the rear surface, a distance between the top surface of the outermost first substructure and the top surface of the adjacent first substructure is equal to or less than 2 μm.

15. The photovoltaic module according to claim 13 , wherein a shape of the polygonal plane includes at least one of a diamond, a square, a trapezoid, a substantially diamond, a substantially square or a substantially trapezoid.

16. The photovoltaic module according to claim 13 , wherein a thickness of the tunnel oxide layer on the top surface of the outermost first substructure is less than a thickness of the tunnel oxide layer on a side surface of the outermost first substructure.

17. The photovoltaic module according to claim 13 , wherein the first texture structure further includes two or more adjacent second substructures that do not stacked on one another, and a one-dimensional size of a top surface of the second substructure away from the rear surface is less than or equal to 45 μm.

18. The photovoltaic module according to claim 17 , wherein the top surface of the second substructure is a polygonal plane.

19. The photovoltaic module according to claim 13 , wherein the tunnel oxide layer includes at least one of a silicon oxide layer, an aluminum oxide layer, a silicon oxynitride layer, a molybdenum oxide layer or a hafnium oxide layer, and the tunnel oxide layer has a thickness ranging from 0.8 nm to 2 nm.

20. The photovoltaic module according to claim 13 , wherein the second passivation layer includes at least one of a silicon nitride layer, a silicon oxide layer or a silicon oxynitride layer, and the second passivation layer has a thickness ranging from 70 nm to 120 nm.