Silicon nitride substrates for power electronics
ZSCHIPPANG E. 1, SCHMIDTNER L. 1, HOERIG J. 2, HERRMANN M. 1
1 Fraunhofer IKTS, Dresden, Germany; 2 Fraunhofer CSP, Halle, Germany
Silicon nitride materials are characterized by excellent mechanical properties and high thermal shock resistance. In addition, the thermal conductivity of Si3N4 materials can be increased to up to 100 W/mK by adjusting the chemical composition and microstructure. This combination of properties makes Si3N4 interesting for power electronics. Such substrates can be produced by tape casting or by multiwire sawing of larger blocks. The paper shows the properties, which can be reached on different powder qualities and sintering conditions. Beside the thermal properties, also the mechanical and electrical properties of substrates produced by multiwire sawing will be discussed in relation to the microstructure.