CERAMIC AND POLYMER THIN-FILMS IN PYROELECTRIC SENSORS - A COMPARATIVE-STUDY

Recently considerable attention has been centered on the use of ferroe lectric thin films in pyroelectric sensor arrays. Integration of the f erroelectric thin film onto technologically important Si wafer offers the possibility to have both the sensor and the electronics on the sam e substrate. The choice of the material and the optimal thermal isolat ion of the sensitive film are the two fundamental problems involved in the fabrication of pyroelectric sensor. In this paper the main emphas is has been to compare the suitability of copolymer like poly(vinylide nefluoride/trifluoroethylene, P(VDF/TrFE) and ceramic like lead zircon ate titanate, PZT, for pyroelectric single element sensors and sensor arrays. Single element sensors with radiation sensitive area of 1 mm(2 ) fabricated from both types of materials onto a SiO2/Si3N4 membrane e xhibited at room temperature, a specific detectivity of 3x10(8) cmHz(1 /2)W(-1). In addition sensor arrays with 128 elements were also fabric ated from both the materials.