Compensation of the Stress Gradient in Physical Vapor Deposited AlScN Films for Microelectromechanical Systems with Low Out-of-Plane Bending.

Thin film through-thickness stress gradients produce out-of-plane bending in released microelectromechanical systems (MEMS) structures. We study the stress and stress gradient of AlScN thin films deposited directly on Si. We show that AlScN cantilever structures realized in films with low average film stress have significant out-of-plane bending when the AlScN material is deposited under constant sputtering conditions.