On readouts of multiple micro/nano resonator sensors with mismatch

Resonators are used to detect small mass changes, which in turn can be used to detect vapours, chemicals, viruses etc. The sensitivity of these detectors can be enhanced by decreasing their mass using micro/nano technologies. However, this leads to a reduction in their effective surface area. To increase the available surface area, several detectors can be manufactured on the same substrate. Parallel excitation and summing of the outputs of the different detectors is the least bandwidth exhaustive readout mechanism for this type of system. However, mismatch between the detectors, which arises due to manufacturing variations, introduces errors in the detection system. In this paper, we study the effect of mismatch on the performance of micro/nano mass sensors with parallel readout. It is shown that resonators with high quality factors, which are otherwise desirable, are also highly susceptible to mismatch. Coupling between the detectors is suggested as a technique to remove the effects of mismatch without increasing the output bandwidth.