Sputter deposited p-type nickel oxide thin films as an anode buffer layer in organic solar cells

P-type NiO thin films were prepared by magnetron sputtering and their characteristic properties were investigated with varying oxygen gas ratio in sputtering ambient. From the measurements of Hall effect and Seebeck coefficient, the films were confirmed to be of p-type conduction. NiO films were applied as the anode buffer layer between ITO and active layer in organic solar cells. Effects of the buffer NiO film on the device performance were systematically studied in this work.