title: High-sensitivity linear piezoresistive transduction for nanomechanical beam resonators.
abstract: 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 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.
authors.affiliation: Instituto de Microelectrónica de Barcelona (IMB-CNM, CSIC), Campus UAB, 08193 Bellaterra, Spain.
authors.forename: Marc
authors.initials: M
authors.lastname: Sansa
authors.affiliation: Instituto de Microelectrónica de Barcelona (IMB-CNM, CSIC), Campus UAB, 08193 Bellaterra, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Fernández-Regúlez
authors.affiliation: Instituto de Microelectrónica de Barcelona (IMB-CNM, CSIC), Campus UAB, 08193 Bellaterra, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Llobet
authors.affiliation: 1] Instituto de Microelectrónica de Barcelona (IMB-CNM, CSIC), Campus UAB, 08193 Bellaterra, Spain [2] Instituto de Microelectrónica de Madrid (IMM, CSIC), Isaac Newton 8 (PMT), Tres Cantos, 28768 Madrid, Spain.
authors.forename: Álvaro
authors.initials: Á
authors.lastname: San Paulo
authors.affiliation: Instituto de Microelectrónica de Barcelona (IMB-CNM, CSIC), Campus UAB, 08193 Bellaterra, Spain.
authors.forename: Francesc
authors.initials: F
authors.lastname: Pérez-Murano