a photovoltaic solar cell comprises a light absorbing layer of n - type crystalline silicon . an emitter layer is on the front side of the n - type crystalline silicon . a front passivation layer physically contacts the emitter layer . a front metal contact is on the front passivation layer and contacts the emitter layer . a back layer of wide bandgap semiconductor physically contacts a back side of the n - type crystalline silicon layer . a back metal contact physically contacts the wide bandgap semiconductor layer .