Ultrasonically driven surface micromachined motor

• Published in: Proceedings IEEE Thirteenth Annual International Conference on Micro Electro Mechanical Systems (Cat. No.00CH36308) pp. 40 - 45
• Main Authors: Kaajakari, V., Rodgers, S., Lal, A.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 2000
• Subjects: Biomembranes; Fabrication; Micromachining; Micromotors; Piezoelectric actuators; Piezoelectric films; Resonance; Rotors; Silicon; Torque
• ISBN: 0780352734; 9780780352735
• ISSN: 1084-6999
• DOI: 10.1109/MEMSYS.2000.838487

The first-ever all-surface micromachined ultrasonic micro-rotor is presented. The rotor is actuated by electrically driving a piezoelectric PZT plate mounted at the back of the silicon die eliminating the need for interconnects and space consuming surface actuators. The rotor operates with a single phase sub-five volt peak-to-peak excitation in atmospheric pressure. The piezoelectric plate is adhesively mounted making the method suitable for actuating micromachines from any surface micromachine process. Two different modes of operation are demonstrated: pulsed and resonant. The pulse actuation results in low rotation rate (0.5-3 RPM) while resonant actuation results in a fast rotation (10-100 RPM). The ability to drive a geared down rotor (50:7), much smaller than the driving rotor indicates high torque output capability.