PYROELECTRIC IR-DETECTOR ARRAYS BASED ON SPUTTERED PZT AND SPIN-COATED P(VDF TRFE) THIN-FILMS/

The choice of the material and an optimal thermal isolation of the sen sitive elements are essential for a pyroelectric sensor with high dete ctivity. In this paper the application of two different ferroelectric materials, a copolymer [poly(vinylidene fluoride/trifluoroethylene), P (VDF/TrFE)] and a ceramic thin film (PZT) for pyroelectric IR sensing, is discussed. The polymer has a low Curie temperature (between 49 deg rees C and 135 degrees C) and hence there is a risk of depolarization at temperatures higher than room temperature. In comparison PZT with a Zr content of 25 at% has a high Curie temperature (450 degrees C) and the sputtered films exhibit self-polarization Single element sensors fabricated from both materials, with a radiation sensitive area of 1 m m(2) on SiO2/Si3N4 membranes exhibit at room temperature a specific de tectivity of about 3 x 10(8) cm.Hz(1/2).W-1. In addition, sensor array s with up to 128 elements were also fabricated.