Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
권호 표지

Alleviating Deformation of MEMS Structure in Surface Micromachining

표면미세가공시 발생하는 MEMS 구조물의 변형 억제

  • 홍석관 (한국생산기술연구원, 정밀금형팀) ;
  • 권순철 (삼성종합기술원) ;
  • 전병희 (인덕대학 컴퓨터응용설계학과) ;
  • 신형재 (삼성종합기술원)
  • Published : 2006.08.01
Download PDF
⟨ Previous Next ⟩

Abstract

By removing sacrificial layer through ashing process, movable MEMS structure on substrate can be fabricated in surface micromachining. However, MEMS structure includes, during the ashing process, the warping or buckling effects due to stress gradient along the vertical direction of thin film. In this study, we presented method for counteracting the unwanted deflection of MEMS structure and designed using character of deposit process to overcome limited design conditions. Unit cell patterns were designed with character of deposit shape, and their final shapes were adopted using Finite Element Method. Finally, RF MEMS switch was fabricated by surface micro machining as test vehicles. We checked out that alleviation effect for deformation of switch improved by 35%.

Keywords

References

  1. Marc, J. M., 'Fundamentals of Micro Fabrications,' The Science of Miniaturization, pp. 262-264, 2001
  2. Peroulis, D., Pacheco, S. and Katehi, L. P. B., 'MEMS Devices for High Isolation Switching and ？Tunable Filtering,' IEEE Transactions on Microwave Theory and Techniques, pp. 1217-1220, 2000 https://doi.org/10.1109/MWSYM.2000.863578
  3. Baek, C. W., Kim, Y. K., Cho, C. H. and Ahn, Y. M., 'Residual Stress Measurement of Micro Gold Electroplated Structure,' International Journal of the Korea Society of Precision Engineering, Vol. 3, No. 2, pp. 72-77, 2002
  4. Vee, Y. J., Park, M. G and Chun, K. J., 'A Sticking Model of Suspended Polysilicon Microstructure Including Residual Stress Gradient and Postrelease Temperature,' Journal of Semiconductor Technology and Science, Vol. 7, pp. 339-344, 1998 https://doi.org/10.1109/84.709653
  5. Woloszyn, J., 'A Method for Controlling Residual Film Stress in LPCVD Polysilicon Films for Surface Micromachined MEMS,' IEEE/SEMI Advanced Semiconductor Manufacturing Conference, pp. 399-403,2004 https://doi.org/10.1109/ASMC.2004.1309604
  6. Schauwecker, B., Strohm, K. M., Simon, w., Mehner, J. and Luy, J. F., 'A New Type of High Bandwidth RF MEMS Switch-Toggle Switch,' Journal of Semiconductor Technology and Science, Vol. 2, pp. 237-245,2002
  7. Shim, J. J., Kim, T. H., Ahn, S. C., Han, D. S. and Lee, S. W., 'Evaluation of the Residual Stress on the Multi-Layer Thin Film made of Different Materials,' Journal of the Korean Society of Precision Engineering, Vol. 20, No. 9, pp. 135-141, 2003
  8. Lee, C. S., Lee, J. H., Choi, C. A., No, K. S. and Wee, D. W., 'Effects of Phosphorus on Stress of Multi-Stacked Polysilicon Film and Single Crystalline Silicon,' J. of Micromech. Microeng., Vol. 9, pp. 252-263, 1999 https://doi.org/10.1088/0960-1317/9/3/306
  9. Peroulis, D., Pacheco, S. P., Sarabandi, K. and Katehi, L. P. B., 'Alleviating the Adverse Effects of Residual Stress in RF MEMS Switches,' IEEE Transactions on Microwave Theory and Techniques, IEEE Transactions on Microwave Theory and Techniques, Vol. 51, pp. 173-176, 2003
  10. Kim, J. H., Hwang, K. C., Lee, B. W., Kim, J. G, Kim, G S., Baek, C. W., Kim, Y. K., Kwon, D.G. and Kim, Y. H., 'Deformation analysis of the surface micromachined MEMS structures due to the plasma ashing process,' KSAS Journal, Vol. 31, No.7, pp. 53-62, 2003
  11. Pacheco, S., Katehi, L. P. B. and Nguyen, CT-C., 'Design of Low Actuation Voltage RF MEMS Switch,' Microwave Symposium Digest, 2000 IEEE MIT-S. International, pp. 165- 168, 2002 https://doi.org/10.1109/MWSYM.2000.860921
  12. Peroulis, D., Pacheco, S. P., Sarabandi, K. and Katehi, L. P. B., 'Electromechanical Considerations in Developing Low-voltage RF MEMS Switches,' IEEE Transactions on Microwave Theory and Techniques, Vol. 51, pp. 259-270, 2003 https://doi.org/10.1109/TMTT.2002.806514
  13. Kwon, U. H. and Lee, W. J., 'Three-Dimensional deposition topography simulation based on new combinations of flux distribution and surface representation algorithms,' Thin Solid Films, Vol. 445, p. 80, 2003 https://doi.org/10.1016/S0040-6090(03)01286-0