Abstract: A method for making a nanoimprinted perovskite film or a perovskite crystal. The method includes applying a solution onto a substrate, thereby forming a precursor film or a precursor crystal, wherein the solution comprises an organo-metal halide precursor in a solvent. The method also includes fabricating an organo-metal halide perovskite film or an organo-metal halide perovskite crystal, wherein fabricating includes annealing the precursor film or the precursor crystal, thereby at least partially evaporating the solvent. The method also includes imprinting the organo-metal halide perovskite film or the organo-metal halide perovskite crystal with a mold, thereby forming an imprinted film or an imprinted crystal. The method also includes separating the mold from the imprinted film or the imprinted crystal, thereby forming the perovskite film or the perovskite crystal.