Research of etching process of Al0.8Sc0.2N based on ICP etching equipment

Etching process is the basis of fabrication of AlScN piezoelectric devices. The mechanism of etching Al
_0.8
Sc
_0.2
N film by inductively coupled plasma etching machine was studied. When the gas flow rates of BCl
₃
/Ar at 80/5 seem, and the tray temperature was 293 K, the etching selectivity ratio of Al
₀
.
₈
Sc
_0.2
N to photoresist was 0.7: 1, and the etching rate was 79 nm/min, the etching inclination angle is 20.2°, and the etching surface roughness is 1.28 nm, which can meet the application of piezoelectric devices based on AlScN thin films.