上海科技大学知识管理系统

This work reports the Lamb wave resonator based on Al0.7Sc0.3N thin films using magnetron sputtering with a single alloy target. The resonator fabrication process based on high Sc doping concentration is discussed. Al0.7Sc0.3N thin films with a 1.2 degrees (0002) rocking curve were obtained with improved crystalline quality and reduced abnormal orientation grains (AOGs). The etching process has been optimized to achieve an etch rate of 127 nm/min and a profile angle of 72 degrees. The dispersion properties of Lamb waves and the influence of different electrodemetals on the coupling coefficient in Al0.7Sc0.3N thin filmswere simulated. Al0.7Sc0.3N Lamb wave resonators operating at approximately 300MHz and 600MHzwere fabricated. A high electromechanical coupling coefficient (k(t)(2)) of 7.74% is reported, with the loaded quality factor of 1119, respectively. A high Figure-of-Merit (FOM) of 86.6 has been achieved for AlScN film based Lamb wave resonators below 1 GHz. The application potential of high scandium concentration (>25%) in resonators and filters is demonstrated.