Abstract
Tensile and fatigue behaviors of the copper film coated by tin (Sn) were investigated considering S-N relationships and scanning electron microscope (SEM) observation of fracture surfaces. The fatigue behavior was investigated considering the effect of load ratio, R. The specimen of 2000 μm width, 8000 μm length and 15.26 μm thickness was fabricated by etching process. Tensile properties were measured using the micro-tensile testing system and in-plane electronic speckle pattern interferometric (ESPI) system for measuring the tensile strain during the test. The fatigue tests of the film were carried out in load-control mode with 40 Hz at three different stress ratios of 0.05, 0.3 and 0.5. The S-N curves, including the slope of the curve and fatigue limit, at the respective stress ratios were obtained. These curves were dependent on the load ratio. Empirical relationships indicating the dependency of the fatigue limit and S-N curve on the load ratio were suggested in this study. SEM observation of the tensile fracture surface showed that the cross-sectional area of the testing section was necked in the direction of the film thickness (i.e. parallel to the substrate surface normal) and some ductile dimples in the fracture surface were present. The fracture of the copper film under cyclic loading was progressed in the transgranular fracture mode.
Similar content being viewed by others
References
Spearing SM (2000) Materials issues in microelectromechanical systems (MEMS). Acta Mater 48:179–196
Nix WD (1989) Mechanical properties of thin films. Metall Mater Trans 20A:2217–2245
Vinci RP, Vlassak JJ (1996) Mechanical behavior of thin films. Annu Rev Mater Sci 26:431–462
Kraft O, Volkert CA (2001) Mechanical testing of thin films and small structures. Adv Eng Mater 3:99–110
Sharpe WN, Bagdahn J (2004) Fatigue testing of polysilicon - a review. Mech Mater 36:3–11
Zhang GP, Volkert CA, Schwaiger R, Arzt E, Kraft O (2005) Damage behavior of 200-nm thin copper films under cyclic loading. J Mater Res 20:201–207
Wang D, Volkert CA, Kraft O (2008) Effect of length scale on fatigue life and damage formation in thin cu films. Mater Sci Eng A 493:267–273
Kraft O, Wellner P, Hommel M, Schwaiger R, Arzt E (2002) Fatigue behavior of polycrystalline thin copper films. Z Metalllk 93:392–400
Cornella G, Vinci RP, Suryanarayanan R, Dauskardt RH, Bravman JC (1999) Observations of low cycle fatigue of Al thin films for MEMS applications. Mater Res Soc Proc 518:81–88
Keller RR, Barbosa N III, Geiss RH, Read DT (2007) An electrical method for measuring fatigue and tensile properties of thin films on substrates. Key Eng Mater 345–346:1115–1120
ASTM E112-96 (2004) e2 Standard Test Methods for Determining Average Grain Size“ Linear Intercept Procedure
Park J-H, An J-H, Kim Y-J, Huh Y-H, Lee H-J (2008) Tensile and high cycle fatigue test of copper thin film. Materialwiss Werkstofftech 39:187–192
Huh Y-H, Kim DI, Kim DJ, Park P, Kee CD, Park J-H (2004) Application of micro-ESPI technique for measurement of micro-tensile properties. Key Eng Mater 270:744–749
Acknowledgements
This research was supported by Korea Research Council of Public Science and Technology (KORP) through the "Development of Advanced Materials Metrology" project.
Author information
Authors and Affiliations
Corresponding author
Additional information
This paper was presented during the Advanced Computational Engineering & Experimenting ACE-X 2008 conference, Barcelona in Spain.
Rights and permissions
About this article
Cite this article
Huh, Y.H., Kim, D.I., Kim, D.J. et al. An Investigation of Fatigue Characteristics of Copper Film. Exp Mech 51, 1033–1038 (2011). https://doi.org/10.1007/s11340-010-9412-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11340-010-9412-9