S. Brida | Searcharxiv

arXiv2008

On the determination of Poisson's ratio of stressed monolayer and bilayer submicron thick films

In this paper, the bulge test is used to determine the mechanical properties of very thin dielectric membranes. Commonly, this experimental method permits to determine the residual stress (s0) and biaxial Young's modulus (E/(1-u)). Associating square and rectangular membranes with different length to width ratios, the Poisson's ratio (u) can also be determined. LPCVD Si3N4 monolayer and Si3N4/SiO2 bilayer membranes, with thicknesses down to 100 nm, have been characterized giving results in agreement with literature for Si3N4, E = 212 $\pm$ 14 GPa, s0 = 420 $\pm$ 8 and u = 0.29.

cs.OH↗

arXiv2008

Micro-tensile tests on micromachined metal on polymer specimens: elasticity, plasticity and rupture

This study is focused on the mechanical characterization of materials used in microelectronic and micro- electromechanical systems (MEMS) devices. In order to determine their mechanical parameters, a new deformation bench test with suitable micromachined specimens have been developed. Uniaxial tensile tests were performed on "low cost" specimens, consisting in electroplated thin copper films and structures, deposited on a polimide type substrate. Moreover, a cyclic mechanical actuation via piezoelectric actuators was tested on the same deformation bench. These experiments validate the device for performing dynamic characterization of materials, and reliability studies of different microstructures.

cs.OH↗