Electrical Study of Si/PS/ZnO:In Solar Cell Structure

AbstractIndium doped zinc oxide (IZO) thin films have been grown on porous silicon, in order to develop solar cell structure, by rf-sputtering at room temperature using indium (4 at %) doped nanocrystalline powder previously synthesized by the sol-gel method. Such layers are polycrystalline with a hexagonal wurtzite structure with a thickness of about 400nm and preferential orientation in (002) crystallographic direction. Electrical study under illumination reveals that this type of nanostructure is promising for solar cell application. By comparing Si/PS/IZO and Si/PS/ZnO/IZO structures, we illustrate a satisfactory photovoltaic conversion with these structures. Also we reveal that interposing an undoped ZnO layer leads to a degradation of PV parameters, specially the short-circuit current (Isc) was affected. In fact, Isc decreases from 3mA to 0.8mA by adding the undoped ZnO thin layer. The open circuit voltage is less affected. A decay of 30mV was recorded. C-V analysis gave a carrier density of about 1016 cm-3 for both cells