Thin film solar cell and method of forming same

1. A method for fabricating a solar cell, comprising:

forming a back contact layer on a front side of a substrate;

forming an absorber layer on the back contact layer;

applying a protective layer on a back side of said substrate;

depositing a buffer layer on said absorber layer, wherein excess buffer materials are deposited on said substrate back side during said depositing; and

removing said protective layer and said excess buffer materials thereon.

2. The method as in claim 1 , wherein said depositing step is performed by chemical bath deposition (CBD).

3. The method as in claim 1 , wherein said depositing step comprises:

dipping said absorber layer in a buffer solution tank; and

cleaning said absorber layer to remove said buffer solution from said absorber layer.

4. The method as in claim 1 , wherein said depositing step is performed at a temperature in a range of about 5° C. to about 120° C.

5. The method as in claim 2 , wherein said dipping step is performed at a constant bath temperature in a range of about 5° C. to about 120° C.

6. The method as in claim 2 , wherein said dipping step is performed at a constant bath temperature in a range of about 50° C. to about 100° C.

7. The method as in claim 2 , wherein said dipping step comprises immersing said absorber layer in said buffer solution tank for a period of about 15 minutes or more.

8. The method as in claim 1 , wherein said protective layer comprises an electrostatic material.

9. The method as in claim 1 , wherein said protective layer comprises a adhesive.

10. The method as in claim 1 , wherein said protective layer comprises an electrostatic tape.

11. The method as in claim 1 , wherein said protective layer comprises a material selected from a group comprising polyethylene terephthalate, polyvinyl chloride, poly propylene, polyethylene vinyl acetate, and polyamide.

12. The method as in claim 1 , wherein said protective layer has a thickness in a range of about 0.5 mm to about 5 mm.

13. The method as in claim 1 , wherein said applying step comprises covering said back side with said protective layer and pressing said protective layer against said back side.

14. The method as in claim 1 , wherein said protective layer is applied so as to include a free end extending past an edge of said substrate, and said removing step comprises:

gripping said protective layer at said free end; and

detaching said protective layer from said substructure.

15. The method as in claim 1 , wherein said absorber comprises copper indium gallium selenide (CIGS).

16. The method as in claim 1 , wherein said buffer layer comprises cadmium sulfide (CdS).

17. A method for fabricating a solar cell, comprising:

providing a solar cell substructure comprising a back contact layer over a front side of a substrate and an absorber layer over said back contact layer;

applying a tape on a back side of said substrate opposite the front side;

depositing a buffer layer around said solar cell substructure including depositing the buffer layer on said absorber layer and excess buffer materials on said tape; and

removing said tape from said substructure and said excess buffer materials thereon.

18. The method as in claim 17 , wherein the step of applying the tape includes applying the tape from a tape roll.

19. A method for fabricating a solar cell, comprising:

forming a back contact layer on a front side of a substrate;

forming an absorber layer on the back contact layer;

applying a protective layer on a back side of said substrate;

depositing a buffer material on said absorber layer and said protective layer using a chemical bath deposition; and

removing said protective layer and the buffer material on the protective layer from said back side.

20. The method as in claim 19 , wherein said removing step is performed using a roller system to transport said solar cell.