High-Angular-Range Electrostatic Rotary Stepper Micromotors Fabricated With SOI Technology

作者：Stranczl Marc^*; Sarajlic Edin; Fujita Hiroyuki; Gijs Martin A M; Yamahata Christophe

来源：Journal of Microelectromechanical Systems, 2012, 21(3): 605-620.

DOI：10.1109/JMEMS.2012.2189367

• Active joint
• differential capacitive sensor
• electrostatic rotary stepper micromotor
• flexural pivot
• folded-beam suspension
• microrobotics
• modal analysis
• silicon-on-insulator (SOI)
• variable-capacitance micromotor

Flexible bearings are advantageous for microelectromechanical systems as they enable precise, accurate, repeatable, and reliable motion without frictional contact. Based on the principle of a rotary folded-beam suspension, we have designed, fabricated, modeled, and characterized an electrostatic rotary stepper micromotor in silicon. Using 3-D finite-element analysis simulations that were corroborated by extensive characterizations performed in quasi-static, transient, and dynamic regimes, we could establish a consistent electromechanical model of the motor. In particular, dynamic nonlinearities such as superharmonic and subharmonic resonances are well described by the proposed model. Two prototypes of monolithic three-phase stepper motors have been fabricated with standard silicon-on-insulator (SOI) technology, using either a two-mask or a single-mask process. The two-mask SOI motor has a rotor diameter of 1.4 mm and has an angular range of 30 degrees (+/- 15 degrees) for a 65-V (130 V-pp) sinusoidal actuation. The single-mask SOI motor has a rotor diameter of 1.8 mm and incorporates a differential capacitive sensor for angular position measurement. It reaches a maximum angular speed of 1 degrees/ms and has an angular range of 30 degrees for a 23-V (46 Vpp) sinusoidal actuation. The exceptional performance of the motor and the demonstration of successful capacitive sensing make it suitable for use as an active joint module in future microrobotic applications. [2011-0339]

• 出版日期2012-6