Fabrication of thin-film, flexible photovoltaic module

• US 6,372,538 B1
• Filed: 03/16/2000
• Issued: 04/16/2002
• Est. Priority Date: 03/16/2000
• Status: Expired due to Term

• Current Assignee: Microsoft Corporation, Sun Harmonics, Ltd., UD Technology Corporation
• Original Assignee: University of Delaware, Global Solar Energy Incorporated (Wei Jun Li)
• Inventors: Wendt, Robert G., Russell, T. W. Fraser, Wiedeman, Scott, Hanket, Gregory M., Birkmire, Robert W.
• Primary Examiner(s): Christianson, Keith
• Application Number:
  US09/527,316
• Time in Patent Office: 761 Days
• Field of Search: 438/61, 438/62, 438/95, 438/484, 438/490, 438/539, 438/907, 438/928, 136/244, 136/258, 136/262, 136/265, 118/718
• US Class Current: 438/95
• CPC Class Codes: H01L 31/0322 comprising only AIBIIICVI chalcopyrite compounds, e.g. Cu In Se2, Cu Ga Se2, Cu In Ga Se2
• CPC Class Codes: H01L 31/0749 including a AIBIIICVI compound, e.g. CdS/CulnSe2 [CIS] heterojunction solar cells
• CPC Class Codes: Y02E 10/541 CuInSe2 material PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A new, large-area, thin-film, flexible photovoltaic structure is disclosed, as well as a general fabrication procedure, including a preferably roll-to-roll-type, process-chamber-segregated, “continuous-motion”, method for producing such a structure. A special multi-material vapor-deposition environment is disclosed to implement an important co-evaporation, layer-deposition procedure performed in and as part of the fabrication procedure. A structural system adapted to create a vapor environment generally like that just referred to is disclosed, as is an organization of method steps involved in the generation of such a vapor environment. Also, a unique, vapor-creating, materials-distributing system, which includes specially designed heated crucibles with carefully arranged, spatially distributed, localized and generally point-like, heated-nozzle sources of different metallic vapors, and a special multi-fingered, comb-like, vapor-delivering manifold structure is shown.

Claims

1. A method of producing a flexible, thin-film photovoltaic (PV) structure comprising

placing a substrate in a processing chamber;

and

applying a layer of a photovoltaic layer structure on the substrate; and

generating internal compression in the applied layer in connection with the step of applying.

2. The method of claim 1, wherein the step of generating takes place simultaneously with the step of applying.

3. The method of claim 1, wherein the layer is a back contact layer.

4. The method of claim 3, wherein the step of generating includes the substep of introducing an impurity into the back contact layer.

5. The method of claim 1, wherein said forming, relative to such sublayer, takes place in a molybdenum (Mo) sputtering process, and the impurity modification mentioned occurs during such sputtering by way of introducing oxygen into the environment wherein Mo sputtering is occurring, thus to create an oxygen-containing characteristic in the Mo-rich sublayer.

6. The method of claim 5, wherein said introducing is performed utilizing water vapor.

7. The method of claim 1 which further includes preparing on and over the other face in such a substrate another Mo-rich sublayer having a coefficient of thermal expansion which substantially matches that of the first-mentioned Mo-rich sublayer.

8. The method of claim 5, wherein said forming further includes the vapor-phase creation of other sublayers, including a copper-indium-gallium-diselenide (CIGS) sublayer directly adjacent such Mo-rich sublayer, a cadmium-sulfide (CdS) sublayer directly adjacent such CIGS sublayer, and an electrically conductive sublayer generally overlying, and operatively connected to, such CdS sublayer.

9. The method of claim 8 which further includes forming an intrinsic-zinc-oxide layer intermediate to such CdS layer and such electrically conductive sublayer.

10. The method of claim 5, wherein said forming further includes the vapor-phase creation of other sublayers, including a copper-indium-diselenide (CIS) sublayer directly adjacent such Mo-rich sublayer, a cadmium-sulfide (CdS) layer directly adjacent such CIS sublayer, and an electrically conductive sublayer generally overlying, and operatively connected to, such CdS sublayer.

11. The method of claim 10, wherein said forming further includes the vapor-phase creation of other sublayers, including a copper-indium-gallium-diselenide (CIGS) sublayer directly adjacent such Mo-rich sublayer, a cadmium-sulfide (CdS) sublayer directly adjacent such CIGS sublayer, and an electrically conductive sublayer generally overlying, and operatively connected to, such CdS sublayer.

12. A method of producing an elongate, flexible, photovoltaic (PV)-material strip comprising

providing an elongate, flexible-strip support substrate,

placing that substrate, in time succession, into different, self-isolated processing chambers, each including roll-to-roll pay-out and take-up structure effective to handle and promote roll-to-roll transport motion of the substrate within that chamber, and

within each chamber, performing different, time-successive sublayer-creation operations which collectively result in the making of an elongate, roll-contained, flexible, PV-material strip which includes, on at least one elongate face, plural-layer, thin-film PV-cell layer structure.

13. A method for creating a thin-film, photovoltaic (PV) structure comprising

providing a flexible, polyimide (PI) substrate, and

forming on one face in such substrate a thin-film, PV-cell layer structure, which forming includes the vapor-phase creating of (1) a sublayer constructed from one of the combinations consisting of (a) copper-indium-gallium-diselenide (CIGS), and (b) copper-indium-diselenide (CIS), with this sublayer having a reception surface, and (2) a sputtered cadmium-sulfide (CdS) sublayer distributed on such reception surface.