High-Dielectric-Constant Filler Effects on PVDF-Based MEMS Pressure Sensors: A Finite-Element Analysis

The performance of polyvinylidene fluoride (PVDF)-based composites in micro-electromechanical (MEMS) capacitive pressure sensors was numerically simulated using COMSOL Multiphysics. We focused on analyzing the effects of incorporating high-dielectric-constant fillers, specifically the perovskite-structured ceramics, %D7L23 DQG 6U7L23, at different weight fractions (e.g., 5-, 10-, 15-, and 20-wt%) into the PVDF matrix. The Mori-Tanaka model predicted the effective Young’s modulus and Poisson’s ratio, while the Bruggeman model estimated the effective dielectric constant. Results showed that filler incorporation enhanced both mechanical stiffness and dielectric constant, leading to increased capacitance and improved sensor sensitivity. However, due to the decoupling of the mechanical and electrostatic simulations, the capacitance increase was significant with higher filler content, while normalized capacitance change ǻ&/&0 varied minimally across different filler fractions. These findings highlight the need for tighter multi-physics coupling or experimental calibration in future work.