THIN-FILM PYROELECTRIC INORGANIC ORGANIC COMPOSITES

Current methods of pyroelectric composite production are incompatible with microelectronics fabrication techniques. Thin-film (1-5mum) inorganic/polymer composites have been produced using a spin-coating method. In the thickness range attainable a quarter-wave cavity for the enhanced absorption of infra-red radiation may be formed. Barium titanate, lead titanate, PZT and lithium tantalate have been incorporated as inorganic dispersoids. A vinylidene fluoride/trifluoroethylene copolymer acts as the host matrix. After the requisite poling procedure the thin film composite materials exhibit pyroelectric coefficients significantly greater than that of 70:30mol% vinylidene fluoride:trifluoroethylene copolymer. They also possess low values of relative permittivity due to the low volume percentages of inorganic material incorporated. As a result the dielectric noise figure of merit is greatly enhanced over conventional polymer pyroelectric materials. These materials are therefore suitable candidates for use in an integrated thermal imaging device.