Photovoltaic device including an inflexible or a flexible substrate and method for manufacturing the same

1. A method for manufacturing a photovoltaic device, the method comprising:

providing a substrate having a first electrode formed thereon;

forming a first unit cell in a first manufacturing system, the first unit cell including a first conductive silicon layer, an intrinsic silicon layer and a second conductive silicon layer, which are sequentially stacked from the first electrode;

exposing to the air either a portion of an intermediate reflector formed on the first unit cell or the second conductive silicon layer of the first unit cell;

forming the rest of the intermediate reflector or the entire intermediate reflector on the second conductive silicon layer of the first unit cell in a second manufacturing system; and

forming a second unit cell on the intermediate reflector in the second manufacturing system, the second unit cell including a first conductive silicon layer, an intrinsic silicon layer and a second conductive silicon layer, which are sequentially stacked.

2. The method of claim 1 , wherein the intermediate reflector is profiled such that a concentration of non-silicon based element in the intermediate reflector is increased more the farther it is from a light incident side.

3. The method of claim 1 , wherein the intermediate reflector is formed by being deposited on the second conductive silicon layer of the first unit cell or by diffusing non-silicon based element onto the second conductive silicon layer of the first unit cell.

4. The method of claim 1 , wherein, after the portion of the intermediate reflector is exposed to the air, the surface of the portion of the intermediate reflector is dry etched.

5. The method of claim 4 , wherein the dry etching is performed by hydrogen plasma.

6. The method of claim 4 , wherein impurity gas is introduced during the dry etching.

7. The method of claim 6 , wherein, when the second conductive silicon layer is an n-type silicon layer, the impurity gas comprises group V elements, and wherein, when the second conductive silicon layer is a p-type silicon layer, the impurity gas comprises group III elements.

8. The method of claim 4 , wherein the dry etching and the formation of the rest of the intermediate reflector are performed in one process chamber.

9. The method of claim 8 , wherein a pressure within the one, process chamber is maintained constant during the formation of both the intermediate reflector and the first conductive silicon layer of the second unit cell.

10. The method of claim 4 , wherein the dry etching and the formation of both the intermediate reflector and the first conductive silicon layer of the second unit cell are performed in one process chamber.

11. The method of claim 10 , wherein a pressure within the one process chamber is maintained constant during the dry etching and the formation of both the intermediate reflector and the first conductive silicon layer of the second unit cell.

12. The method of claim 1 , wherein, after the second conductive silicon layer of the first unit cell is exposed to the air, the surface of the second conductive silicon layer of the first unit cell is dry etched.

13. The method of claim 12 , wherein the dry etching and the formation of the entire intermediate reflector are performed in one process chamber.

14. The method of claim 13 , wherein a pressure within the one process chamber is maintained constant during the formation of both the intermediate reflector and the first conductive silicon layer of the second unit cell.

15. The method of claim 12 , wherein the dry etching is performed by hydrogen plasma.

16. The method of claim 12 , wherein impurity gas is introduced during the dry etching.

17. The method of claim 12 , wherein the dry etching and the formation of both the intermediate reflector and the first conductive silicon layer of the second unit cell are performed in one process chamber.