TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The filler particles comprise a ceramic comprising a material from alumina, titania, zirconia, magnesia, zinc oxide, cesium oxide, yttria, silica, barium titanate, strontium titanate, lead zirconate, or lead zirconate titanate. A functional layer on the surface of the dielectric film comprises fluorine or oxygen. Preferred Property: The filler particles are characterized by a mean particle size of 5-200 nm. The fraction for the filler particles is 0.1-5 wt.% of the dielectric film.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Component: The solvent is acetone, acetonitrile, cyclohexanone, furfuryl alcohol, tetrahydrofurfuryl alcohol, methyl acetoacetate, nitromethane, N,N-dimethylformamide, N-methyl-2-pyrrolidone, butyrolactone, or propylene carbonate.    TECHNOLOGY FOCUS - POLYMERS - Preferred Component: The cyanoresin comprises cyanoethyl pullulan, cyanoethyl polyvinylalcohol, cyanoethyl hydroxyethyl cellulose, or cyanoethyl cellulose. The dielectric polymer film comprises filler particles dispersed in a cyanoresin matrix. A capping layer (28) disposed on the dielectric film comprises polycarbonate, cellulose acetate, polyetherimide, fluoropolymer, parylene, acrylate, silicon oxide, silicon nitride, or polyvinylidene fluoride. Preferred Property: The dielectric polymer film has a thickness of 0.1-50 (preferably 1-20) mu m and a breakdown strength of at least 300 (preferably 500-1000) kV/mm. The capping layer has a thickness of less than 10% of a thickness of the dielectric polymer film. EXAMPLE - A 10 g cyanoethyl pullulan (CR-S) powder was added into 40 g N,N-dimethylformamide to prepare a solution with 10 wt.% polymer. The solution was stirred at room temperature for two hours. The solution was cast on a polished ferrous plate and dried at 100 degrees C in a vacuum oven overnight. The thickness of the deposited film was 13 mu m. For polarization (charge density) measurement, a circular platinum electrode was deposited on top of the film. Since CR-S was a linear dielectric, the energy density E was 30 J/cm3.