High Electrical and Thermal Conductivity of Nano-Ag Paste for Power Electronic Applications

Abstract

The nano-Ag paste consisted of Ag nanoparticles and organic solvents. These organics would be removed by evaporation or decomposition during sintering. When the sintering temperature was 300 °C, the resistivity of sintered bulk was 8.35 × 10 −6 Ω cm, and its thermal conductivity was 247 W m −1 K −1 . The Si/SiC chips and direct bonding copper (DBC) substrates could be bonded by this nano-Ag paste at low temperature. The bonding interface, sintered microstructure and shear strength of Si/SiC chip attachment were investigated by scanning electron microscopy, transmission electron microscopy and shear tests. Results showed that the sintered Ag layer was porous structure and tightly adhered to the electroless nickel immersion gold surface of DBC substrate and formed the continuous Ag-Au interdiffusion layer. The shear strength of Si and SiC chip attachments was higher than 35 MPa when the sintering pressure was 10 MPa. The fracture occurred inside the sintered Ag layer, and the fracture surface had obvious plastic deformation.

Optimizing heat source distribution in sintering molds: Integrating response surface model with sequential quadratic programming

“…In industrial production, the sintering process of nano-Ag paste is usually conducted within the sintering mold. The uniformity of sintering temperature significantly influences the microporous structure and electrical performance of sintered joints [ [4] , [5] , [6] ]. Therefore, ensuring temperature uniformity in the sintering area becomes crucial for enhancing the reliability of the SiC power modules.…”

Low Sintering Temperature Nano-Silver Pastes with High Bonding Strength by Adding Silver 2-Ethylhexanoate

“…The surface-to-volume ratio of nanoparticles is so large that they can be sintered at lower temperatures than bulk materials. Silver nanoparticles are used to prepare conductive inks and pastes due to this property [ 16 , 17 , 18 ]. With a through-silicon via (TSV) connection, nano-silver pastes can bond chips together via copper-to-copper bonding.…”