초록

The present invention relates generally to the field of photovoltaics and more specifically to manufacturing thin-film solar cells using a thermal process. Specifically, a method is disclosed to manufacture a CIGS solar cell by an in-situ junction formation process.

대표청구항 ▼

What is claimed is: 1. A process for preparing a photovolatiac device comprising the steps of: a. providing a p-type semiconductor layer of CIGS on a substrate; b. exposing said p-type semiconductor layer to In+Se+Ga vapor while concurrently decreasing the temperature from a first temperature withi

What is claimed is: 1. A process for preparing a photovolatiac device comprising the steps of: a. providing a p-type semiconductor layer of CIGS on a substrate; b. exposing said p-type semiconductor layer to In+Se+Ga vapor while concurrently decreasing the temperature from a first temperature within a range of about 400�� C. to 600�� C. to a second temperature within a range of about 300�� C. to 450�� C. to form a buffer layer; c. exposing said buffer layer to In+Se+Ga vapor for a period of 2 to 4 minutes in a temperature range of between about 300�� C. to about 450�� C. to produce an n-type semiconductor layer, thus forming a p-n junction. 2. A process for preparing a photovolatiac device comprising the steps of: a. providing a p-type semiconductor layer of CIGS on a substrate; b. exposing said p-type semiconductor layer to In+Se+Ga vapor while concurrently decreasing the temperature from a first temperature within a range of about 400�� C. to 600�� C. to a second temperature within a range of about 300�� C. to 450�� C. to form a buffer layer; c. exposing said buffer layer to In+Se+Ga vapor resulting in deposition of an n-type semiconductor layer with a thickness of about 50 nm to about 500 nm thus forming a p-n junction. 3. A photovoltaic device comprising: a. a substrate with a CIGS layer; b. a buffer layer made by exposing said CIGS layer layer to In+Se+Ga vapor while concurrently decreasing the temperature from a first temperature within a range of about 400�� C. to 600�� C. to a second temperature within a range of about 300�� C. to 450�� C.; and c. an n-type junction made by providing In+Se+Ga vapor for a period of 2 to 4 minutes in a temperature range between about 300�� C. to about 450�� C. 4. The device of claim 3 wherein the second temperature range is about 350�� C. to 400�� C. 5. The device of claim 3 wherein the device is exposed to In+Se+Ga vapor for sufficient time within said second temperature range to deposit a (InxGa1-x)2Se3 layer. 6. The device of claim 5 wherein deposition of said (Inx Ga1-x)2Se3 layer takes place at 350�� C. to 370�� C. 7. A photovoltaic device comprising: a. a substrate with a CIGS layer; b. a buffer layer made by exposing said CIGS layer to In+Se+Ga vapor while concurrently decreasing the temperature from a first temperature within a range of about 400��0 C. to 600 �� C. to a second temperature within a range of about 300�� C. to 450�� C.; and c. an n-type junction made by providing In+Se+Ga resulting in deposition of an n-type semiconductor layer with a thickness of about 50 nm to about 500 nm. 8. The device of claim 7 wherein the temperature range is about 350�� C. to 400�� C. 9. The device of claim 7 wherein the device is exposed to In+Se+Ga vapor for sufficient time within said second temperature range to deposit a (Inx Ga1-x)2Se3 layer. 10. The device of claim 9 wherein deposition of said (Inx Ga1-x)2Se3 layer takes place at 350�� C. to 370�� C.