International Journal of Precision Engineering and Manufacturing

Korean Society for Precision Engineering (한국정밀공학회)
권호 표지

Residual Stress Measurement of Micro Gold Electroplated Structure

  • Baek, Chang-Wook (School of electrical engineering, Seoul National University) ;
  • Kim, Yong-Kweon (School of electrical engineering, Seoul National University) ;
  • Cho, Chul-Ho (School of mechanical engineering, Hanyang University) ;
  • Yoomin Ahn (School of mechanical engineering, Hanyang University)
  • Published : 2002.04.01
Download PDF
⟨ Previous Next ⟩

Abstract

In this paper, a simple method to measure the residual stress in microstructure is presented. In order to find the residual stress in micro-machined beam, the first natural frequency of the beam that has the residual stress inside is analyzed using Rayleigh's energy method. Micro gold electroplated structure is fabricated by surface micro-machining process including electroplating. The made structure is an approximate shape of clamped-clamped beam and its 1 st natural frequency is measured by resonance method. For the better estimation of the residual stress, an equivalent length of micro-fabricated beam to ideal beam is calculated by FEM. The residual stress was estimated from the equivalent length and the measured natural frequency. It was found that a tensile stress was residue in the micro beam structure.

Keywords

References

  1. D. A. Hardwic, 'The Mechanical Properties of Thin Films: A Review,' Thin Solid Films, Vol. 154, pp. 109-124, 1987 https://doi.org/10.1016/0040-6090(87)90357-9
  2. F. R. Brotzen, 'Mechanical Testing of Thin Films,' International Materials Reviews, Vol. 39, No. 1, pp.24-45, 1994 https://doi.org/10.1179/imr.1994.39.1.24
  3. H. Guckel, D. Burns, C. Rutigliano, E. Lovell, and B. Choi, 'Diagnostic Microstructures for the Measurement of Intrinsic Strain in Thin Films,' J Micromech. Microeng., Vol. 2, pp. 86 - 95, 1992 https://doi.org/10.1088/0960-1317/2/2/004
  4. S. P. Baker and W. D. Nix, 'Mechanical Properties of Compositionally Modulated Au-Ni Thin Films: Nanoindentation and Microcantilever Deflection Experiments,' J. Mater. Res., Vol. 9, No. 12, pp.3131 -3144, 1994 https://doi.org/10.1557/JMR.1994.3131
  5. L. Kiesewetter, J. M. Zhang, D. Houdeau, and A. Steckenborn, 'Determination of Young's Moduli of Micromechanical Thin Films Using the Resonance Method,' Sensors and Actuators A, Vol. 35, pp. 153-159,1992 https://doi.org/10.1016/0924-4247(92)80154-U
  6. J. J. Vlassak and W. D. Nix, 'A New Bulge Test Technique for the Determination of Young's Modulus and Possion's Ratio of Thin Films,' J. Mater. Res., Vol. 7, No. 12, pp. 3242-3249, 1992 https://doi.org/10.1557/JMR.1992.3242
  7. D. S. Shim and Y. K. Kim, 'Study on the Characteristics of Gold Electroplating for Micro Structure Fabrication,' Proceedings of the 4th Korean Semiconductor Conference, pp. 511-512, 1997
  8. C. W. Baek, Y. K. Kim, and Y. Ahn, 'Measurement of the Mechanical Properties of Electroplated Gold Microstructure,' Proceedings of the 2nd Korean MEMS Conference, pp. 89-98, 2000
  9. J. J. V. Gill, L. V. Ngo, P. R. Nelson, and C. J. Kim, 'Elimination of Extra Spring Effect at the Step-Up Anchor of Surface-Micromachined Structure,' J. Microelectromechanical Systems, Vol. 7, No. 1, pp.114-121, 1998 https://doi.org/10.1109/84.661393
  10. C. R. Barrett, W. D. Nix, and A. S. Telelman, The Principles of Engineering Materials, Prentice-Hall, p. 540, 1973