Design and fabrication of a micro parallel mechanism system using MEMS technologies

A parallel mechanism is seen as an attractive method of fabricating a multi-degree of freedom micro-stage on a chip. The research team at Arizona State University has experience with several potential parallel mechanisms that would be scaled down to micron dimensions and fabricated by using the silicon process.; The researcher developed a micro parallel mechanism that allows for planar motion having two translational motions and one rotational motion (e.g., x, y, &thetas;). The mask design shown in Appendix B is an example of a planar parallel mechanism, however, this design would only have a few discrete positions given the nature of the fully extended or fully retracted electrostatic motor. The researcher proposes using a rotary motor (comb-drive actuator with gear chain system) coupled to a rack and pinion for finer increments of linear motion. The rotary motor can behave as a stepper motor by counting drive pulses, which is the basis for a simple open loop control system.; This system was manufactured at the Central Regional MEMS Research Center (CMEMS), National Tsing-Hua University, and supported by the National Science Council, Taiwan. After the microstructures had been generated, the proceeding devices were released and an experiment study was performed to demonstrate the feasibility of the proposed micro-stage devices.; In this dissertation, the micro electromechanical system (MEMS) fabrication technologies were introduced. The development of this parallel mechanism system will initially focus on development of a planar micro-stage. The design of the micro-stage will build on the parallel mechanism technology, which has been developed for manufacturing, assembly, and flight simulator applications. Parallel mechanism will give the maximum operating envelope with a minimum number of silicon levels. The ideally proposed mechanism should comprise of a user interface, a micro-stage and a non-silicon tool, which is difficult to accomplish by current MEMS technology limitations. Therefore, this research is focusing on silicon-based technology and expects to achieve the design, fabrication and eventually control purpose.; The micro-stage mechanism was designed and generated based on the special designed three-layer polysilicon surface micromachining techniques. Afterwards, the proceeding structures were released and an experiment study was performed to demonstrate the feasibility of the proposed devices. In addition, the fabrication challenges, prototyping results, improvement methodology and future work were recommended.