Ultrasensitive mass sensor using the out-of-phase vibration eigenstate of intercoupled dual-microcantilevers

This paper reports a kind of intercoupled silicon dual-microcantilevers for ultrasensitive mass detection based on the relative change in the amplitude ratio of the out-of-phase vibration eigenstate of the dual-cantilevers. The structural intercoupling of the dual-cantilevers arises from the coupling overhang connecting them at the base. The whole structure operation is excited by a piezoactuator under ambient conditions. Experimental results indicate that the relative change in the amplitude ratio of the out-of-phase vibration eigenstate of the structure is linear as a function of added mass, and it is more than one order of magnitude greater than the relative change in resonance frequency of in-phase vibration eigenstate.