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Materials selection in micromechanical design: an application of the Ashby approach

By V.T. Srikar and S.M. Spearing

Abstract

The set of materials available to microsystems designers is rapidly expanding. Techniques now exist to introduce and integrate a large number of metals, alloys, ceramics, glasses, polymers, and elastomers into microsystems, motivating the need for a rational approach for materials selection in microsystems design. As a step toward such an approach, we focus on the initial stages of materials selection for micromechanical structures with minimum feature sizes greater than 1 /spl mu/m. The variation of mechanical properties with length scale and processing parameters is discussed. Bounds for initial design values of several properties are suggested and the necessity for the measurement of other properties (especially residual stresses and intrinsic loss coefficients) is discussed. Adapting the methods pioneered by Ashby et al., materials indices are formulated for a number of properties and materials selection charts are presented. These concepts are applied to illustrate initial materials selection for shock-resistant microbeams, force sensors, micromechanical filters, and micromachined flexures. Issues associated with the integration of materials into microsystems are briefly discussed

Topics: TA
Year: 2003
OAI identifier: oai:eprints.soton.ac.uk:22785
Provided by: e-Prints Soton

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Citations

  1. (2003). A critical review of microscale mechanical testing methods used in the design of microelectromechanical systems
  2. (1994). A second-law analysis of thermoelastic damping,”
  3. (2000). An Introduction to Microelectromechanical Systems Engineering.
  4. (1972). Anelastic Relaxation in Crystalline Solids.
  5. (1987). Brunner,“Elastic relationships inlayeredcompositemediawithapproximationforthecaseofthinfilms on a thick substrate,”
  6. (2000). C.Stipe,andD.Rugar,“Qualityfactorsinmicron-andsubmicron-thick cantilevers,”
  7. (1999). de Rooij,and D.Anselmetti,“Soft,entirelyphotplastic probesforscanning force microscopy,”
  8. (2001). Diamond electromechanical micro devices—technology and performance,”
  9. (1995). Dissipation measurements of vacuum-operated single-crystal silicon microresonators,”
  10. (1948). Elasticity and Anelasticity of Metals, Illinois:
  11. (2002). Fundamentals of Microfabrication. Boca
  12. (2002). High-Q micromechanical resonators in CH -reactant-optimized high acoustic velocity CVD polydiamond,”
  13. (1995). Internal friction in freestanding thin Al films,”
  14. (1980). M.F.AshbyandD.R.H.Jones,EngineeringMaterials:AnIntroduction to their Properties & Applications.
  15. (2003). M.Spearing, “Materialsselection formicrofabricated electrostatic actuators,” Sens.
  16. (1991). Materials and shape,”
  17. (2000). Materials issues in microelectromechanical systems
  18. (1997). Materials limits for shape efficiency,”
  19. (1994). Materials selection for precision instruments,”
  20. Mechanical properties of MEMS materials,”
  21. (1989). Mechanical properties of thin films,”
  22. (2001). Microsystem Design.
  23. (2000). Multi-objective optimization in material design and selection,”
  24. (1993). On the influence of the substrate propertiesontheinternalgrowthstressoftitaniumfilmsat250
  25. (1992). On the role of diffusion in phase selection during reactions at interfaces,”
  26. (2002). Physical origins of intrinsic stresses in Volmer-Weber thin films,”
  27. (2002). Residual Stresses in Thin Films, Lecture notes.
  28. (2000). RF MEMS from a device perspective,”
  29. (1995). Selector, Granta Design,
  30. (1990). The effect of thermoelastic internal friction on the Q of micromachined silicon resonators,”
  31. (1989). the engineering properties ofmaterials,”
  32. (1997). The selection of mechanical actuators based on performance indices,”
  33. (2001). The selection of sensors,”
  34. (2002). Thermoelastic damping in fine-grained polysilicon flexural beam resonators,”
  35. (2000). Thermoelastic damping in micro- and nanomechanical systems,”
  36. (2002). Thermoelastic loss in microscale oscillators,”
  37. (2000). VHF free-free beam high-Q micromechanical resonators,”

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