Design and analysis of a dynamic MEM chemical sensor

One possible definition of MicroElectroMechanical Systems (MEMS) encompasses any electro-mechanical structure or device which has feature sizes on the order of 1/spl times/10/sup -6/ m. In this size regime certain effects become important which were not important at more macroscopic scales. These effects include damping and electrostatic actuation methods. In addition, fabrication methods and design of microsystems has progressed to the point where simple structures can be fabricated which isolate certain features or aspects of the structure. Not only can these dynamic effects be utilized in transduction systems, but they can be used to visualize and study systems which cannot readily be duplicated in a macroscopic system. In this paper, an example of microelectromechanical system is presented which utilizes novel dynamics for sensing. Such devices can also be used to investigate the experimental behavior of mathematical systems previously not accessible. The example presented here is a mass/chemical sensor based on parametric resonance.