Stress in Si-glass anodic bonding and its effect on silicon piezoresistive pressure sensor

Anodic bonding between glass wafer and Si wafer are widely used for micro-electro-mechanical system (MEMS) device fabrication and packaging due to the good bonding quality. The residual stress in the bonding interface, which results from the different thermal expansion coefficients of the two wafer materials, is depended on the bonding temperature. In MEMS piezoresistive pressure sensor, the residual stress in anodic bonding, which can affect the accuracy of the device, is investigated by using the finite element method (FEM). The piezoresistive pressure sensor performance is evaluated and the residual stress effect at different temperatures is investigated in this research. The simulation results show that anodic bonding residual stress affect piezoresistive pressure sensor accuracy significantly.