A double-layer MEMS actuator based on ferroelectric polarization inversion in AlScN

This paper presents a piezoelectric double-layer stack based on permanent polarization inversion in ferroelectric Aluminum-Scandium-Nitride solid solution (AlScN). AlScN double layers with a high ScN content of 35% were produced via reactive co-sputtering. The effect of different structuring techniques (Wet vs. Dry) and deposition temperature were investigated in order to combine good reliability with high Sc content double layer systems that yield large piezoelectric displacement and force output. The resulting structure is compared to an AlScN single layer, Aluminum-Nitride and Lead-Zirconate-Titanate (PZT).