A comparison of vibrating beam resonators in Quartz, GaPO_4, LGS and LGT

摘要

The present paper reviews and compares the properties of vibrating beam resonators in length-exten-sional, flexural and cylindrical-torsional modes; resonators are designed and built with new piezoelectric materials: Gallium orthophosphate (GaPO_4), Langasite (LGS) and Langatate (LGT). Their characteristics are compared with the results obtained with the same structures built in classical Quartz crystal. For all 3 new crystals, temperature-compensated cuts have been found for length-extensional and flexural modes by a theoretical analysis. Experiments have been made on test beams fabricated by conventional precision lapping/machining and photolithography to deposit electrodes. The existence of temperature-compensated cuts for length-extensional resonators is experimentally confirmed. The possibilities of using temperature-compensated cylindrical resonators in the torsional modes are analysed and their temperature sensitivity is computed.