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 (σ0) and biaxial Young’s modulus (E/(1 − υ)). Associating square and rectangular membranes with different length to width ratios, the Poisson’s ratio (υ) 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 ± 14 GPa, σ0 = 420 ± 8 MPa and υ = 0.29.

[1]  Shuvo Roy,et al.  Examination of Bulge Test for Determining Residual Stress, Young's Modulus, and Poisson's Ratio of 3C-SiC Thin Films , 2003 .

[2]  Tongxi Yu,et al.  Numerical analysis of theoretical model of the RF MEMS switches , 2004 .

[3]  S. Senturia,et al.  Verification of FEM analysis of load-deflection methods for measuring mechanical properties of thin films , 1990, IEEE 4th Technical Digest on Solid-State Sensor and Actuator Workshop.

[4]  J. A. Taylor The mechanical properties and microstructure of plasma enhanced chemical vapor deposited silicon nitride thin films , 1991 .

[5]  A. Karimi,et al.  Comparison of mechanical properties of TiN thin films using nanoindentation and bulge test , 1998 .

[6]  A. Kingon,et al.  Investigating thin film stresses in stacked silicon dioxide/silicon nitride structures and quantifying their effects on frequency response , 2007 .

[7]  C. Gorecki,et al.  Optomechanical characterisation of compressively prestressed silicon oxynitride films deposited by plasma-enhanced chemical vapour deposition on silicon membranes , 2004 .

[8]  O. Tabata,et al.  Mechanical property measurements of thin films using load-deflection of composite rectangular membranes , 1989 .

[9]  S. Brida,et al.  Design of bossed silicon membranes for high sensitivity microphone applications , 2007 .

[10]  Alain Bosseboeuf,et al.  Vacuum measurement in wafer level encapsulations by interference microscopy , 2006 .

[11]  J. Maibach,et al.  A new analytical solution for the load-deflection of square membranes , 1995 .

[12]  Eric Bonnotte,et al.  Two interferometric methods for the mechanical characterization of thin films by bulging tests. Application to single crystal of silicon , 1997 .

[13]  Hung-Yi Lin,et al.  Mechanical properties of polymer thin film measured by the bulge test , 2007 .

[14]  S. BRODETSKY,et al.  Theory of Plates and Shells , 1941, Nature.

[15]  Hisaaki Tobushi,et al.  Analysis of the mechanical behavior of shape memory polymer membranes by nanoindentation, bulging and point membrane deflection tests , 2000 .

[16]  Processing and Characterization of Micromachined Actuators Based on Proton-Irradiated P(VDF-TrFE) Copolymer , 2005 .

[17]  Joost J. Vlassak,et al.  A new bulge test technique for the determination of Young’s modulus and Poisson’s ratio of thin films , 1992 .