Characterization and improvement of LTCC composite materials for application at elevated temperatures

Abstract

Glass–ceramic composites combine the material properties of its ceramic filler material and the ability of densification via glass assisted sintering. Especially for LTCC materials, were densification has to be achieved at temperatures below 900 °C to enable the usage of metals of improved conductivity in conducting pastes, this densification mechanism in combination with crystallization of the glassy matrix is used successfully. However, the glass’ softening point also limits the use of LTCCs at elevated temperatures, since their mechanical stability is dependent on the remaining glass composition's transition range and its crystallization products. Because LTCC multilayers gain increasing interest in manufacturing sensor devices, a better understanding of their mechanical and electrical behavior in the elevated temperature regime is needed to broaden their field of applications. Therefore, five commercially available LTCC materials were investigated in regard to their temperature dependence of mechanical and electrical properties. Based on the understanding gained from these results, a novel LTCC will be presented and its properties will be discussed.