Solution deposition planarization of stainless steel foil for fabricating Al-doped ZnO film

Abstract

ZnO exhibits various properties, and fabrication of ZnO (including doped ZnO) films are required for device and energy applications. Metals such as stainless steel (SUS) are promising substrates, but deposition of flat films is difficult on as-received metals because of surface roughness. In addition, when films are deposited directly on metals, the electrical resistance is dominated by the substrate. To overcome these problems, solution deposition planarization (SDP) was investigated for SUS. SiO2 solution was spin-coated and heat-treated in air to prepare a flat SDP layer. Flat polycrystalline films of Al-doped ZnO (AZO) were fabricated on the SDP layer. The electrical resistance of AZO/SDP/SUS was determined by AZO, the influence of the SUS is not observed. Thus, the insulation and planarization were simultaneously achieved by the SDP layer. This study shows that polycrystalline AZO films can be deposited on metals with the SDP without a complicated intermediate multilayer structure.