Strategy to mitigate the dipole interfacial states in (i)a-Si:H/MoOxpassivating contacts solar cells

Electrical simulations show that the dipole formed at (i)a-Si:H/MoO
_x
interface can explain electrical performance degradation. We experimentally manipulate this interface by a plasma treatment (PT) to mitigate the dipole strength without harming the optical response. The optimal PT + MoO
_x
stack results in strongly improved electrical parameters as compared to the one featuring only MoO
_x
and to the silicon heterojunction reference cell. Optical simulations and experimentally measured currents suggest that the additional PT is responsible of very limited parasitic absorption overcompensated by the thinner MoO
_x
used (3.5 nm) and by the lower losses in the (i)a-Si:H layer underneath.