A resource efficient design strategy to optimise the temperature coefficient of capacitance of BaTiO3-based ceramics using finite element modelling

摘要

An in-house finite element modelling package is used to simulate the electrical response of core-shell microstructures of BaTiO3-based (BT) dielectric materials as a design strategy for multilayer ceramic capacitors. By combining this method with experimental material properties, both the temperature coefficient of capacitance (TCC) and the volume ratio of undoped BT ceramic (core phase) to chemically doped BT ceramic (shell phase) to optimise temperature stability can be predicted. This is a faster, more reliable and efficient design strategy than current techniques which are based on iterative experimental protocols. This methodology is illustrated using rare earth-free NaNbO3-doped BT (NNBT) ceramics as an example for which we predict and experimentally confirm an optimised volume fraction ratio of 0.66 undoped BT core to 0.34 of a 2.5% NNBT shell.