Control of hole carrier density of polycrystalline Cu2O thin films by Si doping

The effects on the electrical properties of Si doping into Cu2O thin films deposited by reactive sputtering were studied. The hole density increased from 1×1015 to 1×1017 cm−3 with increasing Si content and the minimum resistivity obtained was 12 Ω cm. It was suggested that the electrically active acceptor with an activation energy of 0.19 eV was generated by Si doping. Infrared absorption measurements indicated the formation of silicate in Si-doped Cu2O. The mechanism for Si acting as an acceptor in Cu2O is discussed and modeled based on the silicate formation in Cu2O.