A numerical experimental approach for characterizing the elastic properties of thin films: application of nanocantilevers

作者：Poelma R H^*; Sadeghian H; Noijen S P M; Zaal J J M; Zhang G Q

来源：Journal of Micromechanics and Microengineering, 2011, 21(6): 065003.

DOI：10.1088/0960-1317/21/6/065003

In this paper, a numerical experimental approach for measurement of the effective Young's modulus and its size effect in homogeneous thin films and cantilevers is demonstrated. Cu thin films were used as a case study. The experiment consists in measuring the pull-in instability voltage of electro-static actuated Si nanocantilevers and bilayer Cu/Si nanocantilevers. An electro-mechanical coupled finite element model of the bilayer Cu/Si nanocantilevers was used to extract the effective Young's modulus from the measured pull-in voltage. The fabricated samples consist of 340 nm thick Si cantilevers with 10 and 50 nm thick physical vapor deposited Cu films. White light interferometry was used to measure the cantilever curvature and Stoney's equation was used to calculate the thin film stress. It is shown that the pull-in instability experiment and the cantilever curvature measurement can be used for fast and easy determination of Young's modulus and film stress of 10 and 50 nm thick Cu films, respectively.

• 出版日期2011-6