| Popis: |
The vibrational behaviour of micromechanical elements has been studied theoretically and experimentally. It is found that classical formulae describing the dependence of mechanical resonance frequency on geometrical and material properties are valid for all practical designs using state-of-the-art technology. Only when the elements approach thickness close to atomic dimensions is it necessary to take surface energy effects into account. Experimentally, cantilever beams have been investigated made from a number of materials: silicon, gallium arsenide, glass, aluminum, Kapton¢ and polyvincylidene-fluoride. Simple formulae giving quality factors for mechanical resonances should be used with caution. Experimental values for quality factors measured in vacuum have a range of three orders of magnitude for different materials, reflecting properties of their inner structure. |
