In this dissertation are described two types of micromechanical flexures for guiding mov- able micromechanical structures with applications to high-precision Micro Electro Mechanical Systems (MEMS), whose typical sizes are in the order of 100 pi.
One micromechanical flexure is used as a suspension system to guide oscillating masses without bearings, while the second micromechanical flexure is fashioned into bearing blades, which guide rotating microcomponents by making direct surface contact with elastic bearing preload.
Important mechanical issues influencing the design, microfabrication, and performance optimization of each type of microflexure are identified, quantified, and compared. Key issues for microsuspensions include the control of stiffness and maximum stress through the proper selection of flexure geometry, while those for microblades are the control of deflection, stiffness, and bearing preload through the proper selection of blade material, residual stress and geometry.
With the consideration of mechanical issues, an optimal design theory for each kind of microflexure is developed and applied to the design and optimization of laterally-driven, resonant-structure micromotors and preloaded microbearings, respectively.