Analytical Modelling of Low Pressure Single Boss Sculptured Diaphragm and its Sensitivity Enhancement

The low pressure is measured by using thin Sculptured diaphragm using micro system fabrication technology. The thickness of this diaphragm is reduced to improve sensitivity is achieved by boss like structure to increase the stiffness and reduce nonlinear deflection. This paper brings out the optimum design for single boss sculptured diaphragm. The burst pressure thickness is used to achieve the maximum possible sensitivity. The maximum stress regions identified for the proper placement of four polysilicon piezoresistors which are wired in the form of wheat stone bridge arrangement to estimate the electrical output. The results are obtained using Intellisuite MEMS CAD design tool. Mathematical modelling of single boss sculptured diaphragm results were compared with simulated results. Further the enhancement of sensitivity is analyzed using nonuniform thickness diaphragm and SOI technique. In this paper the low pressure analyzed in the range of (0-1000Pa). The simulation results indicate that the single boss square sculptured diaphragm with 0.9μm yields the higher voltage sensitivity, acceptable linearity with Small Scale Deflection.