Microstructured Multilayered Surface-Acoustic-Wave Device for Multifunctional Sensing

H. Mishra (1) , M. Hehn (1) , Sami Hage-Ali (1) , S. Petit-Watelot (1) , P. Mengue (1) , S. Zhgoon (2) , H. M’jahed (1) , D Lacour (1) , O. Elmazria (1)

1 IJL - Institut Jean Lamour
2 MPEI - Moscow Power Engineering Institute

A multifunctional sensor based on a surface acoustic wave (SAW) device has been fabricated. It allows independent measurements of temperature and applied magnetic field. Optimization of the multilayered device structure leads to a temperature coefficient frequency of the Love wave resonance reduced to zero. The sensitivity to an applied magnetic field is obtained through magnetostriction of a CoFeB layer. By use of shape anisotropy, the variation of intrinsic magnetic anisotropy with temperature is strongly reduced. On one hand, interrogating the device at the Love wave resonance frequency allows to extract the applied magnetic field independently of the temperature in a [130-370K] range. On the other hand, the Rayleigh or Leaky waves are less or not sensitive to applied fields but have a high temperature coefficient of frequency. So interrogating the device at the Rayleigh resonance frequency allows to extract the temperature independently of the magnetic field. In addition, the used resonator geometry offers the possibility for future battery less and wireless interrogation.

Domaines: Acoustique [physics.class-ph]; Micro et nanotechnologies/Microélectronique

H. Mishra, M. Hehn, Sami Hage-Ali, S. Petit-Watelot, P. Mengue, et al.. Microstructured Multilayered Surface-Acoustic-Wave Device for Multifunctional Sensing. Physical Review Applied, 2020, 14 (1), ⟨10.1103/PhysRevApplied.14.014053⟩. ⟨hal-02913853⟩