Tham khảo tài liệu 'micro electronic and mechanical systems 2009 part 6', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 166 Micro Electronic and Mechanical Systems mechanical properties of thin films and various values have been measured Ammaleh 2003 Dual 2004 Yi 1999 . Reported variations in measured values were large requiring extensive research in order to evaluate repeatability accuracy and data reliability of various measurement methods for mechanical properties of MEMS materials. Therefore development of international standards on MEMS materials and their properties measurement methods is one of the primary tasks when MEMS technology is in question. For that reason this chapter intends to give an overview of basic test methods and mechanical properties of MEMS materials. Definitions of mechanical properties of interest are presented along with current test methods for MEMS materials. Also a summary of mechanical properties of various MEMS materials is given. Measured material data for MEMS structural materials is obtained from the literature. Finally the brief overview of the topic is presented in the last section pointing out the necessity of standardization of testing procedures that would accelerate advances in MEMS technology. 2. Mechanical properties MEMS devices use materials such as silicon and many other thin films. These materials had not previously been considered mechanical materials and for that reason are not fully characterized regarding their mechanical properties. The evaluation of the mechanical properties of electrical materials forming MEMS devices is needed to provide the engineering base for full exploitation of the MEMS technology. It is essential both from the aspect of MEMS device performances as well as from the reliability aspect. Mechanical properties of interest fall into three general categories elastic inelastic and strength. In order to predict the amount of deflection from the applied force or vice versa the elastic properties of MEMS materials must be known. Inelastic material properties are important for ductile materials when deformed .
