Design and characterization of high-sensitivity cantilevers

In order to increase the sensitivity of a cantilever-based biosensor, piezoresistive cantilevers with stress concentration holes were designed and fabricated. Firstly the stress distributions and the vertical displacements of the designed cantilevers were simulated through ANSYS analyzing system. Then the relative resistance changes of the piezoresistors as a function of the cantilever vertical displacements were measured. As expected, the stresses are highly concentrated for the designed cantilevers, and this design can obviously result in an improvement on the sensitivity of the surface-stress mode cantilevers