A Multilevel CMOS–MEMS Design Methodology Based on Response Surface Models

We have developed a novel methodology to design systems composed of complementary metal-oxide-semiconductor (CMOS) and microelectromechanical systems (MEMS) parts. This multiscale methodology combines bottom-up modeling and top-down design-space exploration through the following steps: 1) In bottom-up modeling, characteristics of CMOS circuits and MEMS structures are accurately simulated at the circuit and MEMS device level; 2) on the basis of the results of a statistical regression method, these characteristics are abstracted into individual response surface models (RSMs), each with a set of coefficients of design parameters; 3) the models are mathematically connected to describe an elemental unit comprising CMOS and MEMS components; 4) the characteristics of the whole system of elemental units are abstracted into another RSM to cover the system performance; and 5) in top-down design-space exploration, the system requirements are connected to a set of design parameters for the CMOS circuits and MEMS structures by utilizing the RSMs in the reverse direction. To verify the concept, our design methodology was applied to a CMOS-MEMS fingerprint sensor.