Review of thickness-shear mode quartz resonator sensors for temperature and pressure

This work reviews the use of thickness shear mode resonators for temperature sensing and pressure measurement. Advantages of such sensors include an inherently digital format, high resolution, high accuracy, and long-term stability. This work reviews the physical principles involved in the operation of the devices along with quoted sensor performance results. The earliest commercially available temperature sensors were stand-alone units. Their use and commercial success evolved through different stages, depending in part on ancillary electronics available at the time. A number of temperature-sensing applications are ancillary to other thickness shear resonator sensors. Two main categories are separate resonator for temperature compensation and dual-mode operation of a single thickness shear resonator. Dual-mode operation subdivides into use of two modes from different thickness shear mode families or two modes from the same thickness shear mode family. A variety of pressure sensors use the fact that the frequency of a thickness shear resonator changes with stress bias. Such applications divide conveniently into categories dependent on the pattern of stress bias used. (Author)