Study on metal refining process of Sc metal using by microwave irradiation

High-Sc-content ScAlN thin films have attracted significant attention because of their strong piezoelectricity. Akiyama et al. found that the piezoelectricity of ScAlN thin films increases monotonically with increasing Sc concentration, r. The piezoelectricity reaches a maximum at r = 43 at%, at which point the piezoelectric coefficient, d
₃₃
, is five times that of pure AlN. Hashimoto et al. reported that a surface acoustic wave (SAW) resonator based on the ScAlN/6H-SiC structure exhibited resonance Q, anti-resonance Q, and K
₂
values of 340, 240, and 4.5%, respectively, at 3.8 GHz. These values suggest that a ScAlN thin film on a hard substrate should be a suitable SAW wideband filter substrate for next-generation wireless communication systems.