A microball-bearing-supported linear electrostatic micromotor with benzocyclobutene polymer insulating layers

We report for the first time the successful fabrication and operation of a 6-phase, bottom-drive, linear, variable-capacitance micromotor (B-LVCM) using microball bearings and benzocyclobutene (BCB) polymer insulating layers. The device consists of a silicon stator, a silicon slider, and four stainless-steel microballs. The aligning force profiles were extracted from simulated and measured capacitance with a maximum of 0.17 mN per phase at 100 V. The average slider speed at frequencies of 10 Hz and 20 Hz was measured to be 1.82 mm/s and 3.56 mm/s, which is in good agreement with the theoretical value of 1.80 mm/s and 3.60 mm/s, respectively.