Contactless surface acoustic wave gas sensor

A contactless surface acoustic (SAW) wave device and its application as gas sensor is presented. The surface acoustic wave is excited and detected ind uctively, so that no bonding wires are required. In order to show the suita bility of this type of device for sensor applications, we present several m easurements in different temperature regimes. For the detection of organic solvents at room temperature the device was coated with polyepichlorhydrine (PECH), for the detection of NO2 it was coated with copper phthalocyanine (CuPc), and for the detection of methane in the temperature region from 300 degrees C to 450 degrees C it was coated with SnO2. (C) 1999 Elsevier Scie nce S.A. All rights reserved.