The chemical deposition of YSZ and GCO solid electrolyte films by spraying of precursor solutions onto heated substrates was investigated using ultrasonic atomisation. Various precursors (chlorides, acetylacetonates and alcoxides of the corresponding metals) and solvents (ethanol, diethylene glycol, diethylene glycol monobutyl ether, diethylene glycol monobutyl ether acetate and triethylene glycol monobutyl ether) were tested. The experimental results are presented and the mechanism of the film formation is discussed. It is shown that dense thin films of YSZ and GCO are formed from liquid droplets spreading on the substrate surface. A novel technology for thin film electrolyte solid oxide fuel cells which uses etched metallic meshes as an electrolyte support and current collector is demonstrated.