Development of a hybrid MEMS BLDC micromotor

This paper addresses the design of a new hybrid MEMS micromotor. It is a small 3-phases axial flux BLDC motor. The stator is realized following the almost CMOS technology rules used for MEMS manufacture and the coils have two copper layers. The rotor is made of a standard ring permanent magnet assembled over the stator chip. The stator design has been performed using an analytical model also presented in the paper. The microfabrication of the first prototypes is discussed before their characterization. With a Joule efficiency of about 31% for an input power lower then 400 nW, this MEMS micromotor has very good performances and demonstrates the potential of electromagnetic systems at this scale.