Study on Tungsten Metallization and Interfacial Bonding of Silicon Nitride High-Temperature Co-Fired Ceramic Substrates

Abstract

For the first time, Si3N4 HTCC has been prepared using W as the metal phase by high-temperature co-firing (1830 °C/600 KPa/2 h) as a potential substrate candidate in electronic applications. It was discovered that the addition of Si3N4 to the W paste has a significant impact on thermal expansion coefficient matching and dissolution wetting. As the Si3N4 content increased from 0 to 27.23 vol%, the adhesion strength of W increased continuously from 2.83 kgf/mm2 to 7.04 kgf/mm2. The interfacial bonding of the Si3N4 ceramic and the conduction layer was discussed. SEM analysis confirmed that the interface between Si3N4 and W exhibited an interlocking structure. TEM, HRTEM and XRD indicated the formation of W2C and W5Si3 due to the interface reactions of W with residual carbon and Si3N4, respectively, which contributed to the reactive wetting and good adhesion strength between the interface. Suitable amounts of Si3N4 powder and great interfacial bonding were the main reasons for the tough interfacial matching between the Si3N4 ceramic and the conduction layer.