In this letter, experimental investigation of frequency-temperature effects in langatate rectangular cross-section beams are presented. It is shown that a first-order temperature compensated cut exists for the first vibrating mode of length extension.

The present paper reviews and compares the properties of vibrating beam resonators in length-extensional, 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.

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Scanning microdeformation microscopy (SMM) is a near field microscopy in the mesoscopic domain. Such a microscope has become an alternative to the high resolution acoustic microscope that operates at very high frequencies. SMM is based on a vibrating contact tip and piezoelectric detection. The lateral resolution is essentially related to the tip diameter. Classically, the SMM sensor is obtained by a complex mounting process. The tip is glued on a Si cantilever driven by a piezoelectric ceramic. Piezoelectric crystal is an alternative to get a monolithic vibrating cantilever. Quartz crystal, which is the most often used piezoelectric material, can be advantageously replaced by Langasite crystal because of its higher piezoelectric coefficients and its better temperature behaviour.

Quartz length-extension resonators have already been used to get atomically-resolved imaging by frequencymodulation atomic force microscopy. New piezoelectric materials such as Langasite could be appropriate for this application. Theoretical study is reported on length extension resonators in this material. In this paper, an attempt to fabricate micro resonators in Langasite temperature-compensated cuts is prospected. The pointed tip of the micromachined cantilever can be used for atomic force microscopy applications.