A functional ink that includes a precursor sol-gel solution and a solvent is provided. The precursor sol-gel solution is used for forming an oxide dielectric film having a perovskite structure represented by a general formula ABO3, and has been subjected to a partial hydrolysis process in which a viscosity change resulting from the partial hydrolysis process is controlled to be less than or equal to 50%, and water contained in the precursor sol-gel solution is controlled to be greater than or equal to 0.50 times and less than or equal to 10 times by molar ratio with respect to a B site atom contained in the precursor sol-gel solution. The functional ink has a metal oxide concentration and a viscosity that renders the functional ink suitable for being discharged from a nozzle of a liquid droplet discharge apparatus included in a thin film fabrication apparatus.