Design of a MEMS-based capacitive resonator for target analyte detection

Abstract

The present study introduces a microelectromechanical systems (MEMS) capacitive comb-finger resonator designed for the detection of different target analytes by using the detection mechanism based on the resonance frequency shift. This kind of applications is generally needed for a sensing layer capable of absorbing the desired target species in a molecular level, resulting in a change in the mass of the resonator. Therefore, a conceptual fabrication model is also described to form such a layer on the sensor. The dimension of the designed resonator structure is nearly 1766 µm×1998 µm, and the structural thickness of the sensor is planned to be 35 µm thick. Moreover, the design values of rest capacitance and resonance frequency of the structure are nearly 1 pF and 49 kHz, respectively. The inverse of the mass responsivity of the design given in the study is calculated as 370 pg/Hz. In addition to theoretical calculations, the mechanical and electrical simulations are also performed to verify the results. © 2020 Istanbul University. All rights reserved.