Electrospray deposition and characterization of Cu₂O thin films with ring-shaped 2-D network structure

Cu₂OO is a p-type semiconductor with a direct band gap of ~2.1 eV, and is expected for solar cell applications etc. Since monovalent Cu is necessary, compositional control is a key step for Cu₂OO processing. Electrospray is a phenomenon generating ultrafine droplets, when a high voltage is applied to the surface of liquid. In this study, Cu₂OO thin films with unique ring-shaped 2-D network structure have been prepared by using electrospray pyrolysis method. Copper (II) acetate monohydrate, (CH ₃COO)₂Cu·H₂OO was used as a raw material, and D(+) glucose was used as a reducing agent for the reaction from Cu²⁺ to Cu⁺. At the substrate temperature of 300°C, only Cu₂OO was obtained as a crystalline phase. Microstructure, sheet resistance and some optical properties will be discussed.