The Surface Stress on the Microcantilever

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Mapped meshes are made according to requirements as it gives user control over size and shape and deformation of the mesh in all regions The surface stress on the microcantilever surface can be calculated from the observed microcantilever deflection using Stoney’s equation Where Δσs is the differential surface stresses on the surface of the microcantilever, is the Young’s modulus, is the Poisson’s ratio r and h are the radius of curvature and thickness of cantilever beam respectively.For a two-layer piezoresistive microcantilever, the relationship between the surface stress and the relative change in resistance ∆R/R for a piezoresistor is given by Where 1, 1 are the Young’s modulus and thickness of the polysilicon while 2, 2 are the young’s modulus and thickness of piezoresistive, whereas T is the distance from bottom to top of the microcantilever beam that contain the piezoresistive and is the gauge factor of piezoresistive sensor, although above equation applies when polysilicon and piezoresister both are different here [4]. The surface stress associated with the deflection of micro cantilever is commonly calculated using Stoney’s formula, which is simply relates an induced substrate curvature to a surface stress. Piezoresistive microcantilever deflection process involves the embedded of a piezoresistive material such as doped polysilicon on the top surface of the microcantilever to measure the stress change, while the microcantilever beam deflects a stress

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