Afiş Açık Erişim

Device performance enhancement by replacing bulk material with tailor-made metamaterials

2023    Okyar, A. Fethi; Abalı, B. Emek

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Surface acoustic waves (SAW) is an interesting phenomenon which seem to have been heavily utilized in interdigitated transducer (IDT) technology during the last fifty years or more. Love waves for example, which arise when a guiding layer is deposited on a relatively hard piezoelectric substrate are most useful in microfluidic sensor applications because of their shear-horizontal nature. A high sensitivity is one of the key performance indicators for such a sensor which is conventionally attained by material selection and geometry optimization. With the advent of metamaterials more innovative ways to optimize the layer for higher device performance seems to be possible. The thickness of the layer and the conventional means to produce it, however, hamper the possibility of experimenting with new microstructural unit cell geometries. To circumvent this difficulty, we propose to print the guide layer in an IDT-SAW device using a two-photon polymerization printer. With this new printing technology a structural accuracy on the order of 170 and 550 nm in-plane and out-of-plane, respectively can be achieved. The effect of various unit cell geometries can be studied by solving the electro-elastodynamic wave equations using open-source finite-element software FENICS. Upon achieving a desirable behavior by manipulating the internal meso-structure, the layer will be produced in the facilities provided by the Uppsala University. The produced device will be tested and the output will be used to validate the numerical results.