NOVELTY - Photovoltaic cell structure (100) comprises: a substrate (102) including a surface region (104); a first conductor layer; a lower cell structure comprising a first P-type absorber comprising at least a first metal chalcogenide material and/or other suitable semiconductor material; a first N+-type window layer (114) comprising at least a second metal chalcogenide material and/or other suitable semiconductor material; an upper cell structure comprising a second P-type absorber material; a second N+ type window layer; a buffer layer (148); a second conductor layer; and an adhesion layer.    USE - The photovoltaic cell structure is useful for manufacturing a photovoltaic device (claimed).    ADVANTAGE - The photovoltaic structure provides: easy to use processes using convention equipment without further modifications; a multijunction photovoltaic cell structure; high conversion efficiency in converting sunlight into electric energy i.e. 15-20 % greater for the resulting multijunction solar cell; and a much broader range of applicability. The photovoltaic structure can be manufactured in large scale processes, which reduce cost in manufacturing of photovoltaic devices.    DETAILED DESCRIPTION - Photovoltaic cell structure (100) comprises: a substrate (102) including a surface region (104); a first conductor layer overlying the surface region; a 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 having first bandgap of 0.5-1 eV, a first optical absorption coefficient greater than 104cm-1, and a first thickness of 0.5-2 mu m; a first N+-type window layer (114) 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 comprising a second P-type absorber material comprising at least a third metal chalcogenide material overlying the tunneling junction layer, the second P type absorber material having a second band gap of 1-2.2 eV and a second optical absorption coefficient greater than 104 cm-1, a second thickness of 0.5-2 mu m; a second N+ type window layer comprising at least a fourth metal chalcogenide material overlying the second absorber layer; a buffer layer (148) overlying the second N+ type window layer of the upper cell structure, the buffer layer having a resistivity greater than 10k ohm-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.    DESCRIPTION OF DRAWING(S) - The figure shows a photovoltaic cell structure.    Photovoltaic cell structure (100)    Substrate member (102)    Surface region (104)    First window layer (114)    Buffer layer (148)