摘要 |
A film-forming metal solution for supplying metal ions to a solid electrolyte membrane in film formation is provided. In the film formation, the solid electrolyte membrane is disposed between an anode and a substrate as a cathode, and the solid electrolyte membrane is brought into contact with the substrate and a voltage is placed between the anode and the substrate to precipitate a metal on a surface of the substrate from the metal ions contained in the solid electrolyte membrane, so that a metal film of the metal is formed on the surface of the substrate. The film-forming metal solution contains a solvent, and the metal dissolved in the solvent in an ionic state. A hydrogen ion concentration of the film-forming metal solution is within a range of 0 to 10 -7.85 mol/L at 25°C. |