An acoustic waveguide using doubly-bonded silicon/thinned PPT/silicon structures for RF applications

F. Bassignot (1) , E. Courjon (1) , G. Ulliac (1) , Thierry Laroche (1) , J. Garcia (1) , S. Queste (1) , J.-P. Romand (1) , S. Ballandras (1) , R. Petit (2)

1 FEMTO-ST - Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174)
2 DGA CELAR

In this paper, we present new results on the development of piezoelectric transducers based on periodically poled ferroelectric domains in a lithium niobate plate bonded between two silicon wafers. The fabrication of the periodically poled transducers operating in the range 50-500 MHz has been achieved on a 3 inches 500 ¿m thick wafer. These devices then have been bonded on silicon wafers to fabricate a waveguide. Guided elliptic as well as partially guided longitudinal modes are excited. The experimental responses of the tested devices are compared to predicted harmonic admittances, showing a good agreement between both results and allowing for a reliable analysis of the nature of the excited modes. We also show interesting studies of material combinations used to guide ultrasonic waves. Dispersion properties have also been studied for a structure Si/PPT/Si. Operating points corresponding to a specific thickness/period ratio are found. Therefore a new conception with a Si/thinned PPT/Si structure is fabricated.

Domaines: Optique / photonique

F. Bassignot, E. Courjon, G. Ulliac, Thierry Laroche, J. Garcia, et al.. An acoustic waveguide using doubly-bonded silicon/thinned PPT/silicon structures for RF applications. The 22nd European Frequency and Time IEEE International forum, Sep 2009, Rome, Italy. pp.923-926, ⟨10.1109/ULTSYM.2009.5441895⟩. ⟨hal-00485700⟩