Patent ID: 8907206

Claim:
A photovoltaic cell structure for manufacturing a photovoltaic device, the photovoltaic cell structure comprises: a substrate including a surface region; a first conductor layer overlying the surface region; a lower cell structure, the lower cell structure comprising a first P type absorber comprising at least a first metal chalcogenide material and/or other suitable semiconductor material overlying the first conductor layer, the first P type absorber material being characterized by a first bandgap ranging from 0.5 eV to 1.0 eV, a first optical absorption coefficient greater than about 10 4 cm −1 , and a first thickness ranging from 0.5 μm to 2 μm; a first N+ type window layer comprising at least a second metal chalcogenide material and/or other suitable semiconductor material overlying the first P type absorber layer; an upper cell structure, the upper cell structure comprising: a second P type absorber material comprising at least a third metal chalcogenide material, the second P type absorber material being characterized by a second bandgap ranging from 1.0 eV to 2.2 eV and a second optical absorption coefficient greater than about 10 4 cm −1 , a second thickness ranging from 0.5 μm to 2 μm, wherein the second P type absorber material comprises a copper oxide material; a second N+ type window layer comprising at least a fourth metal chalcogenide material overlying the second absorber layer, wherein the fourth metal chalcogenide comprises zinc sulfide; a buffer layer overlying the second N+ type window layer of the upper cell structure; the buffer layer being characterized by a resistivity greater than about 10 kohm-cm; and a second conductor layer overlying the buffer layer; and an adhesion layer disposed between the first N+ type window layer and the second P type absorber material.