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Fabrication and Performance Evaluation of Thin Polysilicon Strain Gauge Bonded to Metal Cantilever Beam

금속 외팔보에 접착된 박막 실리콘 스트레인 게이지의 제작 및 성능 평가

  • Published : 2010.04.01

Abstract

In this paper, we propose a sensor design by using a polysilicon strain gauge bonded to a metal diaphragm. The fabrication process of the thin polysilicon strain gauges having thicknesses of $50\;{\mu}m$ was established using conventional MEMS technologies; further, the technique of glass frit bonding of the polysilicon strain gauge to the stainless steel diaphragm was established. Performance of the polysilicon strain gauge bonded to the metal cantilever beam was evaluated. The gauge factor, temperature coefficient of resistance (TCR), nonlinearity, and hysteresis of the polysilicon strain gauge were measured. The results demonstrate that the resistance increases linearly with tensile stress, while it decreases with compressive stress. The value of the gauge factor, which represents the sensitivity of strain gauges, is 34.0; this value is about 7.15 times higher than the gauge factor of a metal-foil strain gauge. The resistance of the polysilicon strain gauge decreases linearly with an increase in the temperature, and TCR is $-328\;ppm/^{\circ}C$. Further, nonlinearity and hysteresis are 0.21 % FS and 0.17 % FS, respectively.

금속은 가공성이 우수하기 때문에 다양한 형태의 구조물이나 격막을 제작할 수 있다. 이런 금속 구조물이나 격막에 민감도가 월등히 우수한 실리콘 스트레인 게이지를 적용할 경우 그 응용 범위가 다양해질 수 있다. 이에 금속구조물에 다결정 실리콘 스트레인 게이지를 접착한 형태의 센서를 제안하였다. 실리콘 기판을 이용해 박막형 다결정 실리콘 스트레인 게이지를 제작하기 위한 제작공정을 확립하였으며, 제작된 실리콘 스트레인 게이지를 금속 변형부 위에 접착하기 위한 접착공정을 확립하였다. 이후 금속 외팔보에 실리콘 스트레인 게이지를 글래스 프릿 접착하여 성능평가를 실시하였다. 성능평가 결과 게이지팩터는 34.0 의 값을 가졌으며, TCR(Temperature Coefficient of Resistance)은 $-328\;ppm/^{\circ}C$의 값을 가졌다.

Keywords

References

  1. Kovacs, G. T., 1998, Micromachined Transducers Sourcebook, McGraw-Hill, New York, p. 179.
  2. Berns, A., Buder, U., Obermeier, E., Wolter, A. and Leder, A., 2006, "AeroMEMS Sensor Array for High- Resolution Wall Pressure Measurements," Sensors and Actuators A, Vol. 132, pp. 104-111. https://doi.org/10.1016/j.sna.2006.04.056
  3. Kim, S. C. and Wise, K. D., 1983, "Temperature Sensitivity in Silicon Piezoresistive Pressure Transducer," IEEE Transactions on Electron Devices, Vol. 30, No. 7, pp. 802-810. https://doi.org/10.1109/T-ED.1983.21213
  4. Yun, E. J., Kim, J. Y. and Lee, S. T., 2005, "Optimization on the Fabrication Process of Si Pressure Sensors Utilizing Piezoresistive Effect," Journal of IEEK, Vol. 42, No. 1, pp. 19-24.
  5. Malhaire, C. and Barbier, D., "Design of a Polysilicon-on-Insulator Pressure Sensor with Original Polysilicon Layout for Harsh Environment," Thin Solid Films, Vol. 427, pp. 362-366.
  6. Ho, J. J., 2002, "The Design and Fabrication of a Micro-Thermal/Pressure-Sensor for Medical Electro- Skin Application," Solid-State Electronics , Vol. 46, No. 8, pp.1205-1209. https://doi.org/10.1016/S0038-1101(02)00012-6
  7. Schafer, H., Graeger, V. and Kobs, R., 1989, "Temperature-independent Pressure Sensors Using Polycrystalline Silicon Strain Gauges," Sensors and Actuators, Vol. 17, pp. 521-527. https://doi.org/10.1016/0250-6874(89)80040-X
  8. Suski, J., Mosser, V. and Goss, J., 1989, "Polysilicon SOI Pressure Sensor," Sensors and Actuators, Vol. 17, pp. 405-414. https://doi.org/10.1016/0250-6874(89)80027-7
  9. Beeby, S., Ensell, G., Kraft, M. and White, N., 2004, MEMS Mechanical Sensor, Artech House, Norwood, USA, pp. 85-89.
  10. Le Berre, M., Kleimann, P. and Semmache, B., 1996, "Electrical and Piezoresistive Characterization of Boron-Doped LPCVD Polycrystalline Silicon Under Rapid Thermal Annealing," Sensors and Actuators A, Vol. 54, pp. 700-703. https://doi.org/10.1016/S0924-4247(97)80041-6
  11. Leasure, W. A., Woodruff, N. and Gravel, C., 1970, "Glass-Bonding Techniques for Semiconductor Strain Gauge," SESA Spring Meeting, pp. 235-240.
  12. Lu, N.C., Gerzberg, L. and Lu, C. Y., 1981, "Modeling and Optimization of Monolithic Polycrystalline Silicon Resistor," " IEEE transactions on electron devices, Vol. 28, No. 7, pp. 818-830. https://doi.org/10.1109/T-ED.1981.20437
  13. Khan, A. S., Wang, X., 2001, Strain Measurements and Stress Analysis, Prentice Hall, Upper Saddle River, pp. 30-55.
  14. Kovacs, G. T., 1998, Micromachined Transducers Sourcebook, McGraw-Hill, New York, pp. 213-215.
  15. Suzuki, K., Ishihara, T. and Hirata, M., 1985, "Nonlinear Analysis on CMOS Integrated Silicon Pressure Sensor," Electron Devices Meeting, pp.137-140.
  16. Min, N. K., Chun, J. H. and Park, C. W., 1997, "Diaphragm-Type Pressure Sensor with Cu-Ni Thin Film Strain Gauges- : Design, II Fabrication, and Characteristics of a Pressure Sensor,The Journal of the Korea Institute of Electrical and Electronic Material Engineering, Vol. 10, No. 10, pp. 1022-1028.