Preventing harmful polarization of solar cells
In one embodiment, harmful solar cell polarization is prevented or minimized by providing a conductive path that bleeds charge from a front side of a solar cell to the bulk of a wafer. The conductive path may include patterned holes in a dielectric passivation layer, a conductive anti-reflective coating, or layers of conductive material formed on the top or bottom surface of an anti-reflective coating, for example. Harmful solar cell polarization may also be prevented by biasing a region of a solar cell module on the front side of the solar cell.
1. A solar cell module, comprising:
a plurality of solar cells that are electrically connected in series;
an encapsulant that encapsulates the plurality solar cells;
a transparent cover over the encapsulant;
a passivation layer disposed on a front surface of each of the plurality of solar cells; and
a polysilicon layer disposed on the passivation layer,
wherein the polysilicon layer is electrically connected to an interconnect that is electrically connected to a back surface of a solar cell of the plurality of solar cells.
2. The solar cell of module of claim 1 , wherein the polysilicon layer has a thickness of approximately 200 Angstroms.
3. The solar cell module of claim 1 , wherein the passivation layer comprises silicon dioxide.
4. The solar cell module of claim 1 , wherein the transparent cover comprises glass.
5. The solar cell module of claim 1 , further comprising a backsheet facing back surfaces of the plurality of solar cells.
6. A solar cell module, comprising:
a plurality of solar cells that are electrically connected in series;
an encapsulant that encapsulates the plurality of solar cells;
a transparent cover over the encapsulant;
a polysilicon layer disposed between a front surface of each of the plurality of solar cells and the transparent cover, wherein the polysilicon layer is electrically connected to an interconnect that is electrically connected to a back surface of a solar cell of the plurality of solar cells in the series;
a passivation layer disposed between the polysilicon layer and the front surface of each of the plurality of solar cells; and
an anti-reflective coating (ARC) disposed on the polysilicon layer.
7. The solar cell module of claim 6 , wherein the passivation layer comprises silicon dioxide.
8. The solar module of claim 6 , wherein the anti-reflective coating (ARC) comprises silicon nitride.
9. The solar cell module of claim 6 , wherein the transparent cover comprises glass.
10. A solar cell module, comprising:
a plurality of solar cells that are electrically connected in series;
a glass cover over a front surface of each of the plurality of solar cells; and
a polysilicon layer between the front surface of each of the plurality of solar cells and the glass cover,
wherein the polysilicon layer is electrically connected to an interconnect that is electrically connected to a back surface of a solar cell of the plurality of solar cells in the series.
11. The solar cell module of claim 10 , further comprising a passivation layer between the polysilicon layer and the front surface of each of the plurality of solar cells.
12. The solar cell module of claim 11 , wherein the passivation layer comprises silicon dioxide.
13. The solar cell module of claim 10 , further comprising an anti-reflective coating (ARC) disposed on the polysilicon layer.
14. The solar module of claim 13 , wherein the anti-reflective coating (ARC) comprises silicon nitride.