MONOLITHICALLY INTEGRATED DIODES IN THIN-FILM PHOTOVOLTAIC DEVICES

• US 20030213974A1
• Filed: 05/14/2002
• Published: 11/20/2003
• Est. Priority Date: 05/14/2002
• Status: Active Grant

• Current Assignee: Sun Harmonics, Ltd.
• Original Assignee: Global Solar Energy Incorporated (Wei Jun Li)
• Inventors: Woods, Lawrence M., Armstrong, Joseph H., Wiedeman, Scott
• Granted Patent: US 6,690,041 B2
• Time in Patent Office: Days
• US Class Current: 257/184
• CPC Class Codes: H01L 31/02021 for solar cells electrical connection means, e.g. junction boxes, specially adapted for structural association with photovoltaic modules H02S40/34
• CPC Class Codes: H01L 31/0443 comprising bypass diodes integrated or directly associated with the devices, e.g. bypass diodes integrated or formed in or on the same substrate as the photovoltaic cells
• CPC Class Codes: H01L 31/046 PV modules composed of a plurality of thin film solar cells deposited on the same substrate
• CPC Class Codes: H01L 31/0465 comprising particular structures for the electrical interconnection of adjacent PV cells in the module H01L31/0463 takes precedence
• CPC Class Codes: H01L 31/068 the potential barriers being only of the PN homojunction type, e.g. bulk silicon PN homojunction solar cells or thin film polycrystalline silicon PN homojunction solar cells
• CPC Class Codes: H01L 31/125 Composite devices with photosensitive elements and electroluminescent elements within one single body
• CPC Class Codes: H01L 31/18 Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
• CPC Class Codes: Y02E 10/547 Monocrystalline silicon PV cells

Abstract

The present invention relates to the design and manufacture of and includes monolithically integrated diodes for use in planar, thin-film, photovoltaic devices, such as solar cells.

Claims

1. A method for manufacturing diodes comprising the steps of

providing a photoactive apparatus comprising

an electrically insulating substrate layer,

a conductive layer deposited on said substrate layer,

a p-type absorber layer deposited on said conductive layer, and

an n-type window layer deposited on said p-type absorber layer;

a first removing step comprising removing a portion of said conductive layer, said p-type absorber layer, and said n-type window layer;

applying an electrical insulator to a portion of said substrate;

a second removing step comprising removing a portion of said p-type absorber layer and said n-type window layer;

applying a translucent conductor layer to said apparatus;

a third removing step comprising removing a portion of said translucent conductor layer, of said p-type absorber layer, and of said n-type window layer; and

applying an opaque layer to a portion of said translucent conductive layer.

2. The method of claim 1, wherein said substrate layer comprises a material selected from a group consisting of an electrically insulating polyimide, Upilex®

, polyphenylene benzobis oxazole (PBO), polyamide, polyether ether ketone, and metallic foils coated with electrically insulating polyimide, Upilex®

, PBO, polyamide, and polyether ether ketone.

3. The method of claim 1, wherein said conductive layer comprises a material selected from a group consisting of molybdenum, a transparent conductive oxide, brass, titanium, nickel, and nickel-vanadium.

4. The method of claim 1, wherein said p-type absorber layer comprises

a first material selected from a group consisting of copper, copper-silver, and silver;

a second material selected from a group consisting of indium, indium-gallium, indium-aluminum, and aluminum; and

a third material selected from a group consisting of selenide, selenide-sulfer, and sulfur.

5. The method of claim 1, wherein said n-type window layer comprises a material selected from a group consisting of cadmium sulfide, cadmium zinc sulfide, zinc sulfide, zinc selenide, cadmium selenide, zinc-indium selenide, and indium selenide.

6. The method of claim 1, wherein said first removing step comprises a technique selected from a group consisting of chemical etching, laser etching, mechanical etching, and electronic etching.

7. The method of claim 1, wherein said electrical insulator comprises a material selected from a group consisting of a resistive ink, a dielectric, a pottant, and an encapsulant.

8. The method of claim 1, wherein said applying said electrical insulator comprises a technique selected from a group consisting of inkjet deposition, bubblejet deposition, and screen printing.

9. The method of claim 1, wherein said second removing step comprises a technique selected from a group consisting of chemical etching, laser etching, mechanical etching, and electronic etching.

10. The method of claim 1, wherein said translucent conductor layer comprises a material that is transparent.

11. The method of claim 1, wherein said translucent conductor layer comprises a metallic grid.

12. The method of claim 1, wherein said translucent conductor layer comprises a translucent conductive oxide.

13. The method of claim 1, wherein said translucent conductor layer comprises indium tin oxide.

14. The method of claim 1, wherein said third removing step comprises a technique selected from a group consisting of chemical etching, laser etching, mechanical etching, and electronic etching.

15. The method of claim 1, wherein said opaque layer comprises an opaque material.

16. The method of claim 1, wherein said opaque layer comprises a metal.

17. The method of claim 1, wherein said opaque layer comprises a material selected from a group consisting of aluminum, molybdenum, silver, and titanium.

18. The method of claim 1, wherein said opaque layer comprises a material having a plurality of phases, at least one of which is opaque.

19. The method of claim 18, wherein said material having a plurality of phases has at least one phase that is translucent.

20. The method of claim 1, wherein said applying said opaque layer comprises a technique selected from a group consisting of physical vapor deposition, chemical vapor deposition, sputtering, evaporation, and chemical bath deposition.

21. An apparatus for use as a diode comprising

a substrate layer,

a conductive layer deposited on said substrate layer,

an p-type absorber layer deposited on said conductive layer,

a n-type window layer deposited on said p-type absorber layer,

a first trench area on said substrate layer, and formed into said conductive layer, said p-type absorber layer, and said n-type window layer;

an electrical insulator layer deposited on said first trench area;

a second trench area parallel to said first trench area, on said conductive layer and formed into said p-type absorber layer and said n-type window layer;

a translucent conductive layer deposited on said n-type window layer, said electrical insulator, and said second trench area;

a third trench area near said second trench area, on said conductive layer and formed into said p-type absorber layer, said n-type window layer, and said translucent conductive layer; and

an opaque layer deposited on a portion of said translucent conductive layer.

22. The apparatus of claim 21, wherein said substrate layer comprises a material selected from a group consisting of an electrically insulating polyimide, Upilex®

, polyphenylene benzobis oxazole (PBO), polyamide, polyether ether ketone, and metallic foils coated with electrically insulating polyimide, Upilex®

, PBO, polyamide, and polyether ether ketone.

23. The apparatus of claim 21, wherein said conductive layer comprises a material selected from a group consisting of molybdenum, a transparent conductive oxide, brass, titanium, nickel, and nickel-vanadium.

24. The apparatus of claim 21, wherein said p-type absorber layer comprises

a first material selected from a group consisting of copper, copper-silver, and silver;

a second material selected from a group consisting of indium, indium-gallium, indium-aluminum, and aluminum; and

a third material selected from a group consisting of selenide, selenide-sulfer, and sulfer.

25. The apparatus of claim 21, wherein said n-type window layer comprises a material selected from a group consisting of cadmium sulfide, cadmium zinc sulfide, zinc sulfide, zinc selenide, cadmium selenide, zinc-indium selenide, and indium selenide.

26. The apparatus of claim 21, wherein said electrical insulator layer comprises a material selected from a group consisting of a resistive ink, a dielectric, a pottant, and an encapsulant.

27. The apparatus of claim 21, wherein said translucent conductor layer comprises a material that is transparent.

28. The apparatus of claim 21, wherein said translucent conductor layer comprises a metallic grid.

29. The apparatus of claim 21, wherein said translucent conductor layer comprises a translucent conductive oxide.

30. The apparatus of claim 21, wherein said translucent conductor layer comprises indium tin oxide.

31. The apparatus of claim 21, wherein said opaque layer comprises an opaque material.

32. The apparatus of claim 21, wherein said opaque layer comprises a metal.

33. The apparatus of claim 21, wherein said opaque layer comprises a material selected from a group consisting of aluminum, molybdenum, silver, and titanium.

34. The apparatus of claim 21, wherein said opaque layer comprises a material having a plurality of phases, at least one of which is opaque.

35. The apparatus of claim 34, wherein said material having a plurality of phases has at least one phase that is translucent.

38. An apparatus for use as a module of photovoltaic cells with integrated diodes comprising the apparatus of claim 21, wherein said third trench area defines a plurality of photovoltaic devices.

39. The apparatus of claim 38, wherein said photovoltaic devices are selected from a group consisting of photovoltaic cells, diodes, capacitors, and resistors.

36. A method for manufacturing modules of photovoltaic cells with integrated diodes comprising the steps of

providing a photoactive apparatus comprising

an electrically insulating substrate layer,

a conductive layer deposited on said substrate layer,

an p-type absorber layer deposited on said conductive layer, and

a n-type window layer deposited on said p-type absorber layer;

a first removing step comprising removing a portion of said conductive layer, said p-type absorber layer, and said n-type window layer;

applying an electrical insulator to a portion of said substrate;

a second removing step comprising removing a portion of said p-type absorber layer and said n-type window layer;

applying a translucent conductor layer to said apparatus;

a third removing step comprising removing a portion of said translucent conductor layer, of said p-type absorber layer, and of said n-type window layer;

applying an opaque layer to a portion of said translucent conductive layer, and said removing steps further defining a plurality of photovoltaic devices.

37. The method of claim 36, wherein said photovoltaic devices are selected from a group consisting of PV cells, diodes, capacitors, and resistors.

40. An apparatus for use as a protected array of photovoltaic cells comprising

means for generating an electric current from electromagnetic radiation provided in a direction, and

means for providing a one-way path for said current in reverse bias to said direction when said apparatus is not generating electric current.

41. The apparatus of claim 40 wherein said means for generating an electric current further comprises a one-way path for said current in reverse bias to said direction when said apparatus is not generating electric current.

42. The apparatus of claim 40 wherein said means for generating an electric current comprises a flexible thin-film device.

43. The apparatus of claim 40 wherein said means for providing a one-way path comprises a monolithic integration of said means for providing a one-way path into said means for generating an electric current.