Ferroelectric Considerations on Co-Sputtered 30% ALSCN with Different DC+RF Ratios

Aluminum­Scandium Nitride (AlScN) has recently gathered research attention due to proven ferroelectric switching along with enhanced piezoelectric coefficients [1], [2], [3]. The objective of the present work is to evaluate the impact of RF sputtering in the fabrication flow of highly­doped AlScN thin films, thus enabling new ferroelectric microelectromechanical systems (MEMS) functionalities. This paper will compare two co­sputtered 200nm AlScN films, processed with different DC to RF ratios applied to an aluminum target, highlighting the dependence of ferroelectric performance on the input signal characteristic. The work demonstrates how RF sputtering is a pivotal process­parameter in optimizing material characteristics such as coercive field and leakage current in AlScN thin films.