Japanese deep-tech startup Elephantech Inc. announced the successful development of Self-Assembled Copper Nanoparticles (SA-CuNP), a breakthrough technology that imparts dispersibility to copper microparticle pastes through an entirely new mechanism.
In recent years demand for metal sintering materials has been on sharp rise, especially in the power semiconductor field. Among the metal material candidates, copper pastes, offering lower cost and higher reliability than silver, have shown the most potential.
However conventional copper pastes rely on organic dispersants to stabilize particles, which often leads to reduced metal content, inhibited sintering and lower conductivity, posing limits to broad application.
Elephantech’s SA-CuNP technology overcomes the limitations by enabling copper-to-copper dispersion without depending on organic dispersants.
While previously mechanochemical methods have been introduced to attach one metal particles to the surface of another, now SA-CuNP provides a greatly simplified process: mixing the designated copper nanoparticles with copper microparticles will make the nanoparticles spontaneously assemble into a uniform, continuous layer on the microparticle surface.
SA-CuNP also exhibits a unique behavior: once its concentration exceeds a certain level, self-assembly is rapidly triggered. Elephantech defines the threshold as Critical Self-Assembly Concentration (CSAC), a concept similar to Critical Micelle Concentration (CMC). Above CSAC, dispersion stability increases dramatically, enabling higher-performance paste formulations.