Chemical-bath-deposited ZnO and Mg(OH)2 buffer layer for Cu(InGa)Se2 solar cells

ZnO and Mg(OH)(2) thin films were grown by chemical bath deposition (CBD) and applied to the fabrication of Cu(InGa)(SSe)(2) (CIGSSe) solar cells. From the X-ray diffraction (XRD) measurements, the CBD-ZnO film was preferentially oriented toward the (002) plane and the CBD-Mg(OH)(2) film was oriented toward the (001) plane. The optical and electrical properties of CBD-ZnO and CBD-Mg(OH)(2) thin films on a fused silica substrate were investigated and it was found that the films showed a high resistivity and a high transmittance in the visible light wavelength regions. A cell efficiency of 14.3% (V-oc: 557 mV, J(SC): 35.5 mA/cm(2), F.F.: 0.721) was achieved using a CBD-ZnO buffer layer.