<title>Application of pyroelectric P(VDF/TrFE) thin films in integrated sensors and arrays</title>

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Spin coating is a simple method to produce thin copolymer films. By melting and slowly cooling a high rate of (beta) form polar crystallites can be obtained in the films, which was confirmed by X-ray diffraction patterns. By poling at bias fields above 100 V/micrometers , a high spontaneous polarization, and a high pyroelectric coefficient, low dielectric constants and dielectric losses can be achieved. The spontaneous polarization and the Curie point increase with rising context of VDF, while pyroelectric coefficient and dielectric constant decreases. Compositions with a VDF molar content of 70% to 80% are best suited for applying to pyroelectric sensors. the chosen P(VDF/TrFE) shows a spontaneous polarization of 8 (mu) Ccm-2 and a pyroelectric coefficient of 3.5 nCcm-2K-1, a dielectric constant of 8 and a dielectric loss of about 0.018 at 25 degree(s)C. With the help of a computer simulation, the optimum sensor design was achieved in the case of single-element sensors and linear arrays. The care is a self-supporting carrier membrane of about 500 nm Si3N4 and 150 mm SiO2, made by backside etching of silicone with a spin coated (1 - 2) micrometers thick P(VDF/TrFE) film. Built up single-element sensors and linear arrays distinguish themselves by a high voltage responsivity and a high signal-to-noise ratio. They are quite comparable to common sensors of lithium tantalate.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.