Method of fabricating a solar cell with a tunnel dielectric layer
View Patent ↗Methods of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.
1. A method of fabricating a solar cell, the method comprising:
forming, at a first temperature, a surface oxide layer disposed on the substrate by thermal oxidation; and
heating, the surface oxide layer from a temperature below 500 degrees Celsius, to a second temperature above 500 degrees Celsius, wherein the first and second temperature are approximately the same.
2. The method of claim 1 , wherein the first and the second temperature are approximately 565 degrees Celsius.
3. The method of claim 1 , wherein the surface oxide layer is formed by a low-pressure thermal oxidation process.
4. The method of claim 1 , wherein the low-pressure thermal oxidation process is performed in an atmosphere comprising oxygen (O2).
5. The method of claim 1 , further comprising forming a polysilicon layer during the heating.
6. The method of claim 5 , further comprising forming a metal contact above the polysilicon layer.
7. The method of claim 1 , wherein the substrate comprises silicon and the oxide layer comprises silicon oxide.
8. A method of fabricating a solar cell, the method comprising:
consuming a portion of a substrate of the solar cell to provide a surface oxide layer of the substrate, wherein the consuming comprises exposing the substrate to a wet chemical solution; and
heating the surface oxide layer from a temperature below 500 degrees Celsius, to a temperature above 500 degrees Celsius.
9. The method of claim 8 , further comprising, subsequent to heating the surface oxide layer to a temperature above 500 degrees Celsius, cooling back to a temperature below 500 degrees Celsius.
10. The method of claim 8 , wherein heating the surface oxide layer to the temperature above 500 degrees Celsius comprises heating to a temperature of approximately 565 degrees Celsius.
11. The method of claim 8 , wherein the wet chemical solution comprises an oxidizer selected from the group consisting of ozone (O 3 ) and hydrogen peroxide (H 2 O 2 ).
12. The method of claim 8 , wherein the substrate comprises silicon and the oxide layer comprises silicon oxide.
13. The method of claim 8 , further comprising forming a polysilicon layer during the heating.
14. The method of claim 13 , further comprising forming a metal contact above the polysilicon layer.
15. A method of fabricating a solar cell, the method comprising:
consuming a portion of a substrate of the solar cell to provide a surface oxide layer of the substrate, wherein the consuming comprises performing a thermal oxidation process; and
heating the surface oxide layer from a temperature below 500 degrees Celsius, to a temperature above 500 degrees Celsius.
16. The method of claim 15 , further comprising, subsequent to heating the surface oxide layer to a temperature above 500 degrees Celsius, cooling back to a temperature below 500 degrees Celsius.
17. The method of claim 15 , wherein the surface oxide layer is formed by a low-pressure thermal oxidation process.
18. The method of claim 15 , wherein the low-pressure thermal oxidation process is performed in an atmosphere comprising oxygen (O 2 ).
19. The method of claim 15 , further comprises forming a polysilicon layer during the heating.
20. The method of claim 19 , further comprising forming a metal contact above the polysilicon layer.