<title>SAW NO<formula><inf><roman>2</roman></inf></formula> sensors employing copper phthalocyanine as the chemical interface</title>

Abstract

This paper presents some problems concerned with SAW NO2 sensors employing copper phthalocyanine (PcCu) as the chemical interface. The influence of piezoelectric substrate material, crystalline structure and geometry of the PcCu coatings on the sensor sensitivity, and on temperature stability of generated frequency is discussed.The experiments were carried out for SAW delay lines on STX quartz and 128°YX lithium niobate. Our measurements concerned PcCu coating of a and 13 structure. We varied the coating layer thickness from 0. ljtm tol.5tm and its density from O.l7gIcm3 to 1.6g/cm3. it was found that for the investigated range of parameters the -PcCu layer provides several times better sensor sensitivity and temperature stability of SAW delay line generation frequency than cx-PcCu layer of the some mass. This is valid for both used substrates.