COMPOSITION, RAW MATERIAL COMPRISING THE COMPOSITION AND USED FOR CHEMICAL GAS PHASE GROWTH, AND M

PROBLEM TO BE SOLVED : To provide a composition which is suitable, when a bismuth supply source compound and a rare earth element-supplying source compound are mixed and used on the production of a rare earth element-substituted bismuth titatate-based thin film, and to provide a method for producing the thin film using the composition. SOLUTION : This composition comprises 1 pt. mol. of a bismuth compound represented by general formula (I) and 0.01 to 1 pt. mol. of a rare earth element compound represented by general formula (II).