Direct comparison of stylus and resonant methods for determining Young's modulus of single and multilayer MEMS cantilevers

Abstract

As microelectromechnical systems (MEMS) becomes more complex and are produced in even greater numbers it becomes increasingly important to have a full understanding of the mechanical properties of the commonly used MEMS materials. One of the most important properties for MEMS is the Young's modulus. This work describes the direct comparison of two methods often used for measuring the Young's modulus of thin film materials using micro-cantilever test structures: a load-deflection method and a resonant frequency method. The comparison was carried out for a range of materials, different cantilever geometries as well as for single and multilayer materials. It was found that both methods produce results that agree with each other and also agree with the values most often given in the literature.

Determination of the elastic moduli and residual stresses of freestanding Au-TiW bilayer thin films by nanoindentation

“…Note that Equations (2) and (3) do not consider the bilayer structure of the beam, yet. The elastic modulus of each layer was determined by implementing the classic beam theory for a bilayer microcantilevers using the transformed section method [17,33]. The procedure is to transform the crosssection, consisting of a more than one material, into an equivalent cross-section composed of only one material.…”

“…Since then, Guo et al [14] have minimized the error caused by uncertainties in the effective indentation position performing multiple indentations, Tsou et al [12] have improved the analysis by subtracting the indentation effect during deflection, while Florando and Nix [16] have used triangular cantilever in order to avoid inhomogeneous strain distribution during bending. Bilayer cantilevers have been tested by Boyd et al [17] and Fang [18] to extract the elastic moduli using nanoindentation and resonant methods. However, in both cases a complicated Finite Element Modeling (FEM) was required.…”

Young's modulus extraction of epitaxial heterostructure AlGaN/GaN for MEMS application

“…This effect can be described analytically using Eq. by introducing a length Δ L added to the cantilever nominal length L .…”

“…Next, the resonant frequencies of each cantilever with an effective length L + Δ L are calculated using an analytical model (Eq. ) and Δ L was determined to fit the resonance frequencies with simulation.…”

Characterization of micro‐mechanical properties of AlON ceramic by cantilever bending test

“…Hommel quantitatively investigated the mechanical properties of thin polycrystalline Cu films on deformable substrates. Euan Boyd determined Young's modulus of single and multilayer SiC cantilevers by comparing stylus and resonant methods.…”