Granted Patent B2

US 8,912,037 · App. 13/192,545 · Granted Dec 16, 2014

Abstract

Claims (37)

1. A method for making a photovoltaic device, comprising:

disposing a window layer over a substrate;

disposing an absorber layer over the window layer;

wherein disposing the window layer, disposing the absorber layer, or disposing the window layer and the absorber layer, comprises:

oxidizing a source material precursor to form a source material; then

introducing the source material into a deposition zone, and

thereafter, depositing a film comprising a constituent of the source material and oxygen.

2. A method for making a photovoltaic device, comprising:

disposing a window layer over a substrate;

disposing an absorber layer over the window layer; wherein disposing the absorber layer, comprises:

oxidizing a source material precursor that comprises cadmium and tellurium to form a source material comprising a mixture of cadmium, tellurium and oxygen as at least one of an alloy and a compound; then

introducing the source material into a deposition zone; and

thereafter, depositing a film comprising cadmium telluride and oxygen.

3. A method for making a photovoltaic device, comprising:

disposing a window layer over a substrate;

disposing an absorber layer over the window layer;

wherein disposing the window layer, disposing the absorber layer, or disposing the window layer and disposing the absorber layer, comprises:

introducing a source material into a deposition zone, wherein the source material comprises oxygen and a constituent element as a mixture of elements in at least one of an alloy and a compound of oxygen and the constituent element; the constituent element being a constituent of the window layer, of the absorber layer, or of the window layer and the absorber layer; and

depositing a film comprising the constituent element and oxygen.

4. The method of claim 3 , wherein the window layer, the absorber layer, or the window layer and the absorber layer comprise a telluride, a selenide, a sulfide or a hydride.

5. The method of claim 4 , wherein the window layer comprises a semiconductor material selected from the group consisting of cadmium sulfide, cadmium selenide, zinc telluride, zinc selenide, zinc sulfide, indium selenide, indium sulfide, and zinc hydride.

6. The method of claim 4 , wherein the absorber layer comprises a semiconductor material selected from the group consisting of cadmium telluride, cadmium zinc telluride, cadmium sulfur telluride, cadmium manganese telluride, and cadmium magnesium telluride.

7. The method of the claim 3 , wherein disposing the window layer comprises depositing via a vacuum deposition technique selected from the group consisting of evaporation deposition, electron beam physical vapor deposition, sputter deposition, cathode arc deposition, and pulsed laser deposition.

8. The method of claim 3 , wherein disposing the absorber layer comprises depositing via a deposition technique selected from the group consisting of closed space sublimation, diffused transport deposition, and vapor transport deposition.

9. The method of claim 3 , further comprising oxidizing a source material precursor to form the source material.

10. The method of claim 9 , wherein the steps disposing a window layer over a substrate and disposing an absorber layer over the window layer are performed within a deposition chamber; and wherein the step of oxidizing a source material precursor is performed outside the deposition chamber.

11. The method of claim 9 , wherein oxidizing the source material precursor comprises oxidizing at an oxygen pressure ranging from about 100 mTorr to about 10 Torr.

12. The method of claim 11 , wherein oxidizing the source material precursor comprises oxidizing at an oxygen pressure ranging from about 400 mTorr to about 1 Torr.

13. The method of claim 9 , wherein oxidizing the source material precursor comprises oxidizing at a temperature ranging from about 550 degrees Celsius to about 750 degrees Celsius.

14. The method of claim 3 , wherein depositing the film comprises depositing the film to a thickness ranging from about 50 nanometers to about 4 micrometers.

15. The method of claim 3 , wherein depositing the film comprises depositing the film with a concentration of oxygen that ranges from about 4×10 17 cm −3 to 2×10 19 cm −3 within the film.

16. The method of claim 15 , wherein depositing the film comprises depositing the film having a uniform distribution of the concentration of oxygen throughout the film.

17. The method of claim 15 , wherein depositing the film comprises depositing the film having a graded profile of the concentration of oxygen through a thickness of the film.

18. The method of claim 3 , wherein the source material comprises an oxide of the constituent element.

19. The method of claim 3 , further comprising a step of introducing an additional source material into the deposition zone prior to the step of depositing a film; wherein the additional source material comprises an additional constituent of the window layer, of the absorber layer, or of both layers, such that the step of depositing a film includes depositing a film comprising the constituent element, the additional constituent and oxygen.

20. The method of claim 3 , further comprising a step of subjecting the film comprising the constituent element and oxygen to a process treatment.

21. The method of claim 20 , wherein the process treatment is selected from one of: a sulfurization process, a treatment with cadmium chloride, an acid etching process, and combination of a treatment with cadmium chloride and an acid etching process.

Assignments (9)