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R. Reicher, W. Smetana, J. Schuster, A. Adlaßnig:
"An Innovative Thick Film Metallization for Power Electronic Devices";
Talk: 32nd Int. Symposium on Microelectronics (IMAPS 99), Chicago, USA; 10-26-1999 - 10-28-1999; in: "Proceedings of IMAPS 1999", (1999), 728 - 733.

Actually, conductor pastes applied for metallization of aluminium nitride ceramic are glass bonding systems. The glass phase is responsible for adhesion onto the ceramic, unfortunately it also acts as a heat barrier and impairs the excellent thermal conductivity of aluminium nitride. A new glass free thick film metallization system has been developed. The bonding mechanism to provide adhesion of metallization onto the aluminium nitride ceramic is achieved by active metal additives.
Aspects of paste preparation ranging from the derivation of the metallic powder to the assortment of an appropriate organic screen printing medium, which must evaporate completely during the firing process under an inert atmosphere, were investigated. The physical properties of the phases occurring at the interface between the TiCuAg thick film metallization and aluminium nitride ceramic and their contribution to the thermal conductivity as well as to the thermomechanical performance have been characterized theoretically as well as by experiment.
Adhesion properties of the TiCuAg thick film metallization system were tested by measuring tensile strength and compared with commercial glass frit containing copper thick film pastes. Also numerical analysis of temperature and stress distribution within the metallized aluminium nitride ceramic, induced by a continuous as well as a pulsed mode working electronic device has been carried out for this new metallization system and for comparison purpose also for a glass frit containing standard thick film system by means of a finite element program.