Modeling of a PZT5A MEMS resonator disc partially metallized: Annular metallization

An extension of the orthogonal polynomial approach in order to solve wave propagation in a MEMS resonator disc in the case of annular metallization is reported in the following paper. The disc is made from PZT5A and has been divided into two areas, the outer one with electrodes and the inner without electrodes. The formulation is based on expressing different displacement components by means of Legendre polynomials series and harmonic functions for solving the goverening equation of motion and Maxwell equations in the system of cylindrical coordinates. Alternating source and boundary conditions are directly incorporated into the governing equations. The electro-acoustic behavior of the MEMS resonator concern of presenting the resonant and anti-resonant frequencies, the electrical input admittance and the field of axial and radial mechanical displacement components. Obtained results are compared with those reported in the literature, good agreement was proved.