Design and simulation of sensitivity diaphragm of untouched-mode capacitive pressure sensor

Central island structure of the sensitive diaphragm used in untouched-mode capacitive pressure sensor solved the problem of the different, nonlinear, compensation circuit complexity. Through the optimization structural design for polysilicon sensitivity diaphragm, flexibility, stress and other mechanical properties also be analyzed. Capacitance values, sensitivity and linearity of the sensitive diaphragm are calculated at different applied pressure. According to the optimizing design, when applied pressure varying between 0. 2∼1. 4× 10⁵Pa, capacitance value changed between 0. 0251∼0. 0281 pF. By analyzing rate of flexibility in XY plane at the same position of the two different diaphragm structure. Central island structure is 49. 4% below the plane diaphragml. 7%. Central island structure has a better sensitivity and linear.