title: Experimental-Numerical Comparison of the Cantilever MEMS Frequency Shift in presence of a Residual Stress Gradient.
abstract: The dynamic characterization of a set of gold micro beams by electrostatic excitation in presence of residual stress gradient has been studied experimentally. A method to determine the micro-cantilever residual stress gradient by measuring the deflection and curvature and then identifying the residual stress model by means of frequency shift behaviour is presented. A comparison with different numerical FEM models and experimental results has been carried out, introducing in the model the residual stress of the structures, responsible for an initial upward curvature. Dynamic spectrum data are measured via optical interferometry and experimental frequency shift curves are obtained by increasing the dc voltage applied to the specimens. A good correspondence is pointed out between measures and numerical models so that the residual stress effect can be evaluated for different configurations.
authors.affiliation: Department of Mechanics, Politecnico of Torino, C.so Duca degli Abruzzi,24 - 10129, Torino, Italy. alberto.ballestra@polito.it.
authors.forename: Alberto
authors.initials: A
authors.lastname: Ballestra
authors.affiliation: Department of Mechanics, Politecnico of Torino, C.so Duca degli Abruzzi,24 - 10129, Torino, Italy. aurelio.soma@polito.it.
authors.forename: Aurelio
authors.initials: A
authors.lastname: Somà
authors.affiliation: Faculty of Mechanical Engineering, State University of Campinas, CEP 13083-970 Campinas, Brazil. pava@fem.unicamp.br.
authors.forename: Renato
authors.initials: R
authors.lastname: Pavanello
keywords: Frequency shift; MEMS; micro cantilever; residual stress gradient