Methods of forming a conductive transparent oxide film layer for use in a cadmium telluride based thin film photovoltaic device
View Patent ↗Methods are generally provided for forming a conductive oxide layer on a substrate. In one particular embodiment, the method can include sputtering a transparent conductive oxide layer on a substrate at a sputtering temperature from about 50° C. to about 250° C., and annealing the transparent conductive oxide layer at an anneal temperature of about 450° C. to about 650° C. Methods are also generally provided for manufacturing a cadmium telluride based thin film photovoltaic device.
1. A method for forming a conductive oxide layer on a substrate, the method comprising:
sputtering a target at a sputtering temperature of about 50° C. to about 250° C. to deposit a transparent conductive oxide layer on a substrate; and,
annealing the transparent conductive oxide layer at an anneal temperature of about 450° C. to about 650° C., wherein the transparent conductive oxide layer is annealed in an annealing atmosphere having a pressure of about 0.5 Torr to about 50 Torr.
2. The method as in claim 1 , wherein the transparent conductive oxide layer comprises cadmium.
3. The method as in claim 1 , wherein the comprising comprises cadmium stannate.
4. The method as in claim 1 , wherein the transparent conductive oxide layer has a thickness of about 100 nm to about 1 μm.
5. The method as in claim 1 , wherein the transparent conductive oxide layer has a thickness about 150 nm to about 400 nm.
6. The method as in claim 1 , wherein the sputtering temperature is about 75° C. to about 200° C.
7. The method as in claim 1 , wherein the transparent conductive oxide layer is annealed in an annealing atmosphere comprising an inert gas.
8. The method as in claim 7 , wherein the annealing atmosphere further comprises cadmium sulfide.
9. The method as in claim 7 , wherein the inert gas is argon.
10. The method as in claim 1 , wherein the anneal temperature is about 575° C. to about 650° C.
11. The method as in claim 1 , wherein the transparent conductive oxide layer is annealed for about 1 minute to about 30 minutes.
12. The method as in claim 1 , wherein the transparent conductive oxide layer is annealed in an annealing atmosphere comprising a reducing gas.
13. The method as in claim 12 , wherein the reducing gas is hydrogen sulfide.
14. The method as in claim 1 , wherein annealing is begun within 1 hour of sputtering the transparent conductive oxide layer.
15. A method for manufacturing a cadmium telluride based thin film photovoltaic device, the method comprising:
sputtering a target at a sputtering temperature of about 50° C. to about 250° C. to deposit a transparent conductive oxide layer on a substrate;
annealing the transparent conductive oxide layer at an anneal temperature of about 450° C. to about 650° C., wherein the transparent conductive oxide layer is annealed in an annealing atmosphere comprising an inert gas, the annealing atmosphere having a pressure of about 0.5 Torr to about 50 Torr;
forming a resistive transparent buffer layer over the transparent conductive oxide layer;
forming a cadmium sulfide layer over the resistive transparent layer; and,
forming a cadmium telluride layer over the cadmium sulfide layer.
16. The method as in claim 15 , wherein the comprising comprises cadmium stannate.
17. The method as in claim 15 , wherein the sputtering temperature is about 75° C. to about 200° C.
18. The method as in claim 15 , wherein the sputtering temperature is about 100° C. to about 200° C.
19. The method as in claim 15 , wherein the further comprises cadmium sulfide.
20. The method as in claim 15 , wherein the anneal temperature is about 575° C. to about 650° C.