Static High Voltage Actuation of Piezoelectric AlN and AlScN Based Scanning Micromirrors.
Chris StoeckelKatja MeinelMarcel MelzerAgnė ŽukauskaitėSven ZimmermannRoman ForkeKarla HillerHarald KuhnPublished in: Micromachines (2022)
Piezoelectric micromirrors with aluminum nitride (AlN) and aluminum scandium nitride (Al 0.68 Sc 0.32 N) are presented and compared regarding their static deflection. Two chip designs with 2 × 3 mm 2 (Design 1) and 4 × 6 mm 2 (Design 2) footprint with 600 nm AlN or 2000 nm Al 0.68 Sc 0.32 N as piezoelectric transducer material are investigated. The chip with Design 1 and Al 0.68 Sc 0.32 N has a resonance frequency of 1.8 kHz and a static scan angle of 38.4° at 400 V DC was measured. Design 2 has its resonance at 2.1 kHz. The maximum static scan angle is 55.6° at 220 V DC, which is the maximum deflection measurable with the experimental setup. The static deflection per electric field is increased by a factor of 10, due to the optimization of the design and the research and development of high-performance piezoelectric transducer materials with large piezoelectric coefficient and high electrical breakthrough voltage.