A New Fabrication Process for Lamb Wave Resonator with IDT-IDT Structure

This work presents a novel fabrication process for IDT-IDT structured AlScN based Lamb wave resonators (LWRs). Utilizing wafer-level transfer technology through Si-SiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> bonding, effectively addresses the issue of poor AlScN film deposition quality above patterned IDT electrodes. The process successfully produced IDT-IDT structured LWRs on 8-inch wafers with electrode periods of 2 μm and 12 μm, operating at 412.8 MHz and 2280.4 MHz. Experiment results show that the fabricated LWRs exhibit high Q values of 2521 and 1495, with $k_t^2$ values of 5.78% and 2.80%, respectively, at a 9.5% Sc doping concentration.