High-sensitivity linear piezoresistive transduction for nanomechanical beam resonators

Marc Sansa, Marta Fernández-Regúlez, Jordi Llobet, Álvaro San Paulo, Francesc Pérez-Murano
2014 Nature Communications  
Highly sensitive conversion of motion into readable electrical signals is a crucial and challenging issue for nanomechanical resonators. Efficient transduction is particularly difficult to realize in devices of low dimensionality, such as beam resonators based on carbon nanotubes or silicon nanowires, where mechanical vibrations combine very high frequencies with miniscule amplitudes. Here we describe an enhanced piezoresistive transduction mechanism based on the asymmetry of the beam shape at
more » ... the beam shape at rest. We show that this mechanism enables highly sensitive linear detection of the vibration of low-resistivity silicon beams without the need of exceptionally large piezoresistive coefficients. The general application of this effect is demonstrated by detecting multiple-order modes of silicon nanowire resonators made by either top-down or bottom-up fabrication methods. These results reveal a promising approach for practical applications of the simplest mechanical resonators, facilitating its manufacturability by very large-scale integration technologies.
doi:10.1038/ncomms5313 pmid:25000256 fatcat:uqk7vhv7lzee3jseunmn4o3qmq