| Current trends in the miniaturization of structures requires the use of smaller and smaller components that comprise them. Development of these microcomponents and, in turn, mechanical microstructures, requires, in addition to the integrated use of advanced design, analysis, and fabrication methodologies, state-of-the-art test and measurement methodologies. Two such methodologies, with unique capabilities for rapid characterization of MicroElectroMechanical Systems (MEMS), were developed in the course of this dissertation. More specifically, the new methodologies developed herein are: (1) an opto-electronic holographic methodology (OEHM), and (2) an optoelectronic laser interferometric based methodology (OLIM).; MicroElectroMechanical Systems are a unique class of mechanisms created using integrated circuit (IC) fabrication processes. Microgears and microengines, smaller than a gnat's eye, are groups of MEMS created by such a process. MEMS offer opportunities in sensor/actuator applications development, e.g., airbag sensors, or transmissions, and unique and challenging opportunities for design, analysis, and test methodologies.; Until this dissertation, test methodologies, in particular, were practically non-existent. This dissertation produced two brand new methodologies for characterization of MEMS. OEHM is demonstrated through an investigation of freely vibrating atomic force microscope (AFM) microprobes/microsensors. These microsensors, which range in length from 125 μm to 450 μm, and from 0.6 μm to 2.7 μm in thickness, have resonant frequencies ranging from approximately 11 kHz to 2 MHz, and maximum displacements of 0.75 μm to approximately 2.5 μm. Accurate knowledge of operating frequencies and their corresponding mode shapes has important ramifications on design and optimization of AFMs. To demonstrate the OELIM, motions of a 64 μm diameter microgear, driven at speeds up to 360,000 rpm, are investigated. Manufacturing tolerances result in gaps between the microgear and its hub. Consequently, the microgear tilts. The dissertation's unique methodologies permitted measurements of tilt angles of less than 15 mrad, and deflections below 0.5 μm. Knowing how individual microgears behave is important when many such gears are combined to form transmissions.; Future work will concentrate on the development of shape measurement capabilities and their integration with the test and measurement methodologies developed during the research pursued in this dissertation. Such integrated test and measurement methodologies will provide new tools that will facilitate future developments, characterization, and implementation of MEMS. |
