Development of a Hybrid MEMS BLDC Micromotor

This paper addresses the design of a new hybrid microelectromechanical systems (MEMS) micromotor. It is a small three-phase axial flux brushless dc (BLDC) motor. The stator is developed following the almost-standard CMOS technology rules used for MEMS manufacturing, and the coils have two copper layers. The rotor is made of a ring permanent magnet assembled over the stator chip. The stator design has been performed using an analytical model also presented in this paper. The microfabrication of the first prototypes is presented, followed by their characterization. With an efficiency of about 42% for an input power of 310 nW, this MEMS micromotor has very good performance and demonstrates the potential of electromagnetic systems at this scale.