Fabrication and testing of surface micromachined polycrystalline SiC micromotors

The authors present the fabrication and testing of surface micromachined polycrystalline silicon carbide micromotors. A new multilayer fabrication process utilizing low temperature deposition and micromolding techniques was developed to create the desired SiC structural components. Typical operating voltages of salient-pole and wobble micromotors in room air were 100 and 80 V, respectively. Wobble micromotors were tested at room temperature in atmospheres of argon, nitrogen, oxygen, and room air (25% humidity). The gear ratio as a function of applied voltage was higher for operation in room air as compared with the other gases, suggesting a relationship between gear ratio and relative humidity. In addition, micromotors were tested at elevated temperatures and exhibited stable operation up to 500/spl deg/C.