Densification Behavior and Microstructure Evolution of LTCC Film Constrained by Rigid Substrate

LTCC films constrained by rigid substrate were sintered at different temperatures ranging from 760 °C to 800 °C. An optical dilatometer together with a rocking arm was employed to record sintering strains of the constrained films during the sintering process. The densification behavior of constrained films was systematically studied through the measured sintering strains by comparing with that of freely sintered films. For the constrained films, the final density was smaller and the activation energy for the densification was larger than that of the freely sintered ones. Moreover, anisotropic microstructure was induced by the tensile stress.