Performance of inductively coupled oxygen sensors

We have designed an inductively coupled oxygen sensor suitable for operation at temperatures in the 500-1000 C range. A prototype sensor has been fabricated on alumina substrates using screen printing. The sensor consists of an RLC resonant circuit where the oxygen-sensitive ZnO resistor varies the quality factor. Changes in the quality factor are measured using an admittance bridge coupled to the RLC circuit by a probe coil. We report here on optimization of the sensor design and we contrast the measured and predicted performance of the prototype sensor.