Significant tuning of dispersive mode coupling in doubly clamped MEMS beam resonators using thermally induced buckling effect

TL;DR

This paper demonstrates how thermally-induced buckling can significantly tune dispersive mode coupling in MEMS beam resonators, enabling adjustable coupling strengths for advanced device applications.

Contribution

It introduces a method to control mode coupling in MEMS resonators through buckling, supported by a theoretical model explaining the tunability mechanism.

Findings

Significant tuning of mode coupling coefficient achieved experimentally.

Theoretical model links buckling-induced shape changes to coupling strength.

Provides insights for designing MEMS devices with adjustable mode coupling.

Abstract

Dispersive mode coupling is a promising mechanism for the development of advanced micro/nanoelectromechanical devices. However, strong coupling strength remains a key challenge limiting the practical applications of dispersive mode coupling effect. Here, we experimentally demonstrate the significant tuning of the mode coupling coefficient of two flexural vibrational modes in a doubly-clamped MEMS beam resonator using thermally-induced buckling effect, which enables variable coupling strengths to be implemented for practical applications. Furthermore, a theoretical model is developed to describe the mode coupling coefficient, showing that the tunability is owing to the breakdown of the symmetric shape of the MEMS beam caused by buckling. Moreover, the theoretical model defines a simple relation between the coupling coefficient and the nonlinearity of the two coupled modes. These results provide valuable insight into physical mechanisms underlying dispersive mode coupling effect, as well as pave the way for the development of advanced MEMS devices with application-specified mode coupling strength.