Abstract: The lateral vibration of microresonator suspended with one-side straight-leg beams is simple modeled in a superfluous system with three unknown variables. Methods are given to calculate the resonant frequency, elastic coefficient and lateral displacement. Comparing with the microresonator suspended with double-side straight-leg beams that is a superfluous system with five unknown variables, it is found that the mechanical properties of the former are quite different with that of later. It is clearly different from the microresonator suspended with double-side straight-leg beams from the analysis results that the resonant frequency, elastic coefficient and lateral displacement will change with the variation of distance between the two straight-leg beams in microresonator suspended with one-side straight-leg beams. After the distance exceeds a certain value, the change of all the above three variables is very small and tends to a fixed number. Similarly, the resonant frequency also will change with the variation of beam thickness in later, but there is no such phenomenon in the former. So an explanation is given according to the different redundance for the two different superfluous systems. The theoretical resonant frequencies of microresonators suspended with one-side straight-leg beams are coincident with the measured values. The biggest error between them is 12.07%. The above results provide reference for the structure design of microresonator.

Key words: Electrostatic silicon microresonator, Micro electromechanical systems(MEMS), One-sided flexural suspension, Properties analysis