Stoichiometric Lithium Niobate Crystals: Towards Identifiable Wireless Surface Acoustic Wave Sensors Operable up to 600$^\circ$C

Jérémy Streque; Thierry Aubert; Ninel Kokanyan; Florian Bartoli; Amine Taguett; Vincent Polewczyk; Edvard Kokanyan; Sami Hage-Ali; Pascal Boulet; Omar Elmazria

doi:10.1109/lsens.2019.2908691

arXiv · 1907.09998

Stoichiometric Lithium Niobate Crystals: Towards Identifiable Wireless Surface Acoustic Wave Sensors Operable up to 600$^\circ$C

Jérémy Streque·Thierry Aubert·Ninel Kokanyan·Florian Bartoli·Amine Taguett·Vincent Polewczyk·Edvard Kokanyan·Sami Hage-Ali·Pascal Boulet·Omar Elmazria

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Abstract

Wireless surface acoustic wave (SAW) sensors constitute a promising solution to some unsolved industrial sensing issues taking place at high temperatures. Currently, this technology enables wireless measurements up to 600-700$^\circ$C at best. However, the applicability of such sensors remains incomplete since they do not allow identification above 400$^\circ$C. The latter would require the use of a piezoelectric substrate providing a large electromechanical coupling coefficient K 2 , while being stable at high temperature. In this letter, we investigate the potentiality of stoichiometric lithium niobate (sLN) crystals for such purpose. Raman spectroscopy and X-ray diffraction attest that sLN crystals withstand high temperatures up to 800$^\circ$C, at least for several days. In situ measurements of sLN-based SAW resonators conducted up to 600$^\circ$C show that the K 2 of these crystals remains high and stable throughout the whole experiment, which is very promising for the future achievement of identifiable wireless high-temperature SAW sensors.

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Jérémy Streque, Thierry Aubert, Ninel Kokanyan, Florian Bartoli, Amine Taguett, Vincent Polewczyk, Edvard Kokanyan, Sami Hage-Ali, Pascal Boulet, Omar Elmazria. 2019-05-02. Stoichiometric Lithium Niobate Crystals: Towards Identifiable Wireless Surface Acoustic Wave Sensors Operable up to 600$^\circ$C. https://doi.org/10.1109/lsens.2019.2908691

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