A method of producing a bismuth layered compound that includes the steps of providing a substrate, dissolving Bi, Sr and Ta containing compounds in an organic solvent to form a solution having a Bi:Sr:Ta volume ratio of 2:1:2, evaporating the solution and depositing the evaporated solution onto the substrate, heating the substrate to form a thin film having a fluorite structure, and heating the thin film in an oxidizing atmosphere to convert the thin film having a fluorite structure to a thin film comprising Bi2SrTa2O9.