Material requirements for power and high temperature multilayer ceramic capacitors (MLCC)

Recent trends and progresses in power electronics rely on fast, miniaturized, high current and high temperature switching semiconductors. However, in electronics system design, passive components technologies, in particular capacitors, limit their full exploitation. The goal of the present paper is, firstly, to analyse the capacitor technologies, in particular ceramic technologies for the limits set by high current, high voltages, high temperatures, high frequencies, and by cost items. Secondly, for each of the identified limits, to define the tools and technologies that are capable to overcome it. The new technologies include a new PLZT based antiferroelectric ceramic material with high switching field, copper inner electrode for the multilayer construction, firing in reducing atmosphere, applying a sputter method for the outer connecting electrode combined with silver sintering of a flexible termination or of a pressfit connector. The third goal is to show how the new technologies are applied such that the cost forecast in production scale is giving a good economic perspective for future use in power electronic systems. Finally, specific applications in power electronics are selected and described, where the benefits resulting from the new technologies are made evident.