Thermal stability and characteristic properties of pressureless sintered Ag layers formed with Ag nanoparticles for power device applications

摘要

Thermal stability and characteristic properties of the microstructure of sintered Ag layers were examined with morphological, crystallographic and mechanical analyses. The sintered Ag layer was prepared by a pressureless sintering procedure with an Ag paste including Ag nanoparticles having a diameter distribution of 50-300 nm. The microstructure of the sintered Ag had a porosity of 8% and was morphologically and crystallographically dense. Cross-sectional SEM images showed that pores having a diameter of 0.2-1.0 μm were homogenously located in an Ag matrix. The dense microstructure remained intact after storage at 250 °C and for 1000 h. Shear strength of the sintered Ag layers was over 40 MPa and elastic modulus of the sintered Ag layer was 14 GPa before and after the storage tests at 250 °C and for 1000 h.