Abstract
Microelectromechanical system (MEMS) contains microsensors, microactuators, micromechanical structures, and integrated circuits. Since the micromachining fabrication processes are improved drastically, plenty of micromachined devices have been developed and commercialized presently. However the performance of these devices are not only depend s on the geometry design and fabrication process improvement, but on the control of mechanical properties of thin film materials. The mechanical properties, which are important issues but generally ignored by designer, usually make the devices have a deviated performance different from its initial design. Therefore, a simple and accurate method to characterize the mechanical properties of thin film materials is very important. This thesis intends to characterize the mechanical properties of thin film materials using the micromachined structures. Base on the solid mechanics, the mechanical properties such as Young’s modulus, Poisson’s ratio and coefficient of thermal expansion are characterized by micromachined structures under different micromachining processes (Bulk/Surface micromachining). At least two types of characterized mechanisms were exploited to characterize each of mechanical properties for improving the accuracy. Furthermore, the thermal behaviors of thin films were also being discussed. Finally, every characterized mechanism exploited in this thesis not only can role as test key to characterize the mechanical property of thin film during the batch fabrication of devices, but also combined with other mechanism to be a test key group with more performance.