Analytical methodology and design of advanced test structure for the mechanical characteristics of microactuator materials

The electrostatic test structure was presented to measure the micromechanical properties of micromaterials as thin films forming the microactuators. The test structure was fabricated by using the surface micromachining processes and driven by the electrostatic force. In order to measure the fracture toughness, the sharp notch in the test structure was introduced by using the etching process. The displacement and deflection of the test structure under the electrostatic force was on the basis of the beam bending theory. An analytical model was proposed to evaluate the fracture toughness by experimental determination of crack propagation from the variations of capacitance and voltage. Additionally, an acceleration test for evaluation of the long-term reliability of the microactuator device was performed to predict the lifetime of a gold micromirror plane used in DVD (Digital Video Disk) by analyzing the resonant frequency and capacitance.