Buffer layers for photovoltaic devices with group V doping
According to the embodiments provided herein, a photovoltaic device can include a buffer layer adjacent to an absorber layer doped p-type with a group V dopant. The buffer layer can have a plurality of layers compatible with group V dopants.
1. A photovoltaic device comprising:
a substrate;
a transparent conductive oxide layer over the substrate;
a buffer layer residing over the transparent conductive oxide layer, the buffer layer including:
a first buffer layer comprising a discontinuous first layer including MnO x and a void formed through the discontinuous first layer occupied by a material other than MnOx; and
a second buffer layer;
an absorber layer over the buffer layer, the absorber layer including a group V dopant, and the absorber layer having a first and second surface; and
a back contact layer over the absorber layer.
2. The photovoltaic device of claim 1 , wherein the first buffer layer includes a group V dopant.
3. The photovoltaic device of claim 1 , wherein the first buffer layer is adjacent to the absorber layer.
4. The photovoltaic device of claim 1 , wherein the discontinuous first layer of MnO x has a bandgap that substantially matches the bandgap of an adjacent semiconductor.
5. The photovoltaic device of claim 1 , further comprising a barrier layer between the substrate and the transparent conductive oxide layer.
6. The photovoltaic device of claim 5 , further comprising a conducting layer on top of the back contact layer.
7. The photovoltaic device of claim 6 , further comprising a back support on top of the conducting layer.
8. The photovoltaic device of claim 1 , wherein the layer of MnO x comprises MnO 2 or Mn 2 O 3 .
9. The photovoltaic device of claim 1 , wherein the layer of MnO x comprises Mn 3 O 4 .
10. The photovoltaic device of claim 1 , wherein the discontinuous first layer of MnO x has a dosage of Mn that is at least 0.05 μg/cm 2 .
11. The photovoltaic device of claim 1 , wherein the buffer layer further includes a third buffer layer including tin oxide and the second buffer layer includes a different material than the third buffer layer.
12. The photovoltaic device of claim 11 , wherein the buffer layer is adjacent to the absorber layer.
13. The photovoltaic device of claim 12 , wherein the second buffer layer includes magnesium oxide.
14. The photovoltaic device of claim 12 , wherein the second buffer layer includes zinc magnesium oxide.
15. The photovoltaic device of claim 12 , wherein the second buffer layer includes silicon dioxide.
16. The photovoltaic device of claim 12 , wherein the second buffer layer includes MnO x .
17. The photovoltaic device of claim 12 , wherein the second buffer layer includes silicon nitride.
18. The photovoltaic device of claim 12 , wherein the third buffer layer is thicker than the second buffer layer.
19. The photovoltaic device of claim 1 , wherein:
the buffer layer further comprises at least one intermediate layer between the first buffer layer and the second buffer layer; and
the at least one intermediate layer is composed of a different material than both the first buffer layer and the second buffer layer.
20. The photovoltaic device of claim 19 , wherein the second buffer layer is thicker than the at least one intermediate buffer layer.
21. The photovoltaic device of claim 19 , wherein the at least one intermediate buffer layer includes zinc magnesium oxide.
22. The photovoltaic device of claim 21 , wherein the second buffer layer includes silicon dioxide.
23. A photovoltaic device comprising:
a substrate;
a transparent conductive oxide over the substrate;
a buffer layer including two layers with one of the two layers being a discontinuous layer including MnO x having a void formed through the discontinuous layer occupied by a material other than MnOx and the buffer layer residing over the transparent conductive oxide;
an absorber layer, residing over the buffer layer, the absorber layer including a group V dopant, and the absorber layer having a first and second surface;
a back contact layer over the absorber layer; and
a conducting layer over the back contact layer.
24. A photovoltaic device comprising:
a substrate;
a transparent conductive oxide layer over the substrate;
a buffer layer including two layers with one of the two layers being a discontinuous layer including MnO x having a void formed through the discontinuous layer occupied by a material other than MnOx and the buffer layer residing over the transparent conductive oxide;
an absorber layer over the buffer layer, the absorber layer including a group V dopant, and the absorber layer having a first and second surface;
a back contact layer over the absorber layer;
a conducting layer over the back contact layer; and
a back support over the conducting layer.