Photovoltaic cell and methods for producing a photovoltaic cell
View Patent ↗A photovoltaic device is provided that includes a substrate, a first transparent conductive layer positioned on the substrate, a plurality of transparent conductive rods positioned on the first transparent conductive layer and having a growth direction, the growth direction extending in a direction away from the substrate, a photovoltaically active layer covering the plurality of transparent conductive rods rods and a conductive layer positioned on the photovoltaically active layer.
1. A method comprising:
providing a substrate comprising a first transparent conductive layer,
depositing a seed layer onto the first transparent conductive layer using a mask to produce a structured seed layer,
building up a plurality of transparent conductive rods on the structured seed layer,
depositing a photovoltaically active layer onto the transparent conductive rods,
depositing a conductive layer onto the photovoltaically active layer.
2. The method according to claim 1 , wherein
a closed seed layer is deposited and portions of the closed seed layer are removed.
3. The method according to claim 1 , wherein
the seed layer is deposited by depositing a solution comprising zinc acetate dehydrate and ethanol onto the substrate and heat treating.
4. The method according to claim 1 , wherein
the transparent conductive rods are built up using a hydrothermal synthesis technique.
5. The method according to claim 1 , wherein
the transparent conductive rods are built up by immersing the substrate in a solution comprising zinc nitrate hexahydrate and hexamethylenetetramine at a temperature T for a time t.
6. The method according to claim 5 , wherein
the temperature T lies in the range 60 to 120° C.
7. The method according to claim 5 , wherein
the time t lies in the range of 20 minutes to 100 minutes for a temperature T of 95° C.
8. The method according to claim 1 , wherein
the photovoltaically active layer is a silicon layer comprising a charge separating junction.
9. The method according to claim 8 , wherein
the silicon layer is deposited by chemical vapour deposition.
10. The method according to claim 8 , wherein
the silicon layer is deposited by plasma enhanced chemical vapour deposition.
11. The method according to claim 1 , wherein
the conductive layer is transparent.
12. The method according to claim 10 , wherein
the conductive layer is deposited by chemical vapour deposition.
13. The method according to claim 1 , wherein
the first transparent conductive layer is deposited by low pressure chemical vapour deposition.
14. The method according to claim 1 , wherein
the photovoltaically active layer is deposited conformally onto the transparent conductive rods.
15. The method according to claim 1 , wherein
the conductive layer is deposited conformally onto the photovoltaically active layer.
16. The method according to claim 1 , wherein the structured seed layer comprises a plurality of discrete seed regions, the seed regions having a diameter in a range of about 100 nm to about 150 nm, and
wherein the building up of the transparent conductive rods occurs on the seed regions.