| Summary: | 碩士 === 國立交通大學 === 機械工程系 === 87 === This thesis focuses on the design and fabrication of micromotors. By using the surface micromachining technique, we designed and fabricated an electrostatic side-drive wobble micromotor based on Deng's geometric design.. Moreover, we also made improvement on her design and process. There are two major new ideas: the first is the fabrication of the etching stop which protects the bottom of the anchor from being damaged during releasing. With this etching stop, an additional electric path from the rotor to the substrate is also established. This electric path is always effective and would reduce the potential difference between the rotor and the substrate. The second is the 1 mm bearing clearance composed by a mixed-layer, a wet oxide and a PECVD oxide layer. The former has the advantage of high conformality while the latter consumes no polysilicon. This thick bearing clearance can solve the interlocking problem posed by the non-uniform RIE process and may induce a lift force on the rotor. Due to the efforts on process and the modified design, we fabricated a micromotor with the free moving and separated rotor, the stator, and the bearing connecting the rotor and the anchor. But because of the low performance of the RIE machine we've used, the sidewalls were not vertical as expected. Improvement on this process step is required. In addition to the design and the fabrication process, we also followed Trimmer's derivation and established the torque model for our micromotor geometry. By this model we can estimate the driving torque of the micromotor under ideal operation conditions.
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