Fabrication of copper oxide thin films by the drop chemical deposition technique

Copper oxide thin films were deposited by the drop chemical deposition technique using an aqueous solution containing CuSO4 and Na2SO3. The deposited films were cubic crystalline structure and had O/Cu ratio of ∼0.77 with a very small amount of sulfur. The surface morphology of the films appeared compact without any crack. In the optical transmission measurement, a clear absorption edge was observed near 800 nm wavelength. Photo-electrochemical measurement confirmed the p-type conductivity and photosensitivity of the films. CuxO-based heterojunctions with ZnO were fabricated, and rectification properties and weak photovoltaic effects were observed.