ACOUSTIC-WAVE THERMAL SENSITIVITY - TEMPERATURE TEMPERATURE COMPENSATION IN MICROSENSORS

In the field of temperature measurements, microsensors are based on di fferent physical transduction principles, such as semiconductor parame ters (conductivity, pn junction voltage), metallic junction voltage (t hermocouple) or elastic wave velocity variations (bulk or surface acou stic waves). This paper discusses acoustic-based temperature microsens ors. Thermal effects are modelled and applications to bulk and surface acoustic wave microsensors are presented. Moreover, the-use of temper ature sensing for other measurements (thermal flow and humidity sensor s) is described. Improvements of sensitivities and response time by va rying the operating temperature are also pointed out for gas detectors . Possibilities of temperature compensation in silicon acoustic wave m icrosensors are discussed.