Nanoindentation characterization of sintered porous Cu nanoparticles used in power electronics packaging – A molecular dynamic simulation study

As a critical part of speeding up industrial electrification, power electronics, and its packaging technology are undergoing rapid development. Cu nanoparticle sintering technology has therefore received extensive attention for its excellent performance in the die-attachment layer, where the mechanical properties are essential to be known for design for reliability. Both sintering and subsequent nanoindentation were studied by simulation. The effect of porosity on the nanoindentation response was investigated by setting different initial packing densities. In addition, the impact of indenter size and indentation positions on the nanoindentation response were discussed. The nanoindentation behaviors were studied by extracting loading-displacement (P-h) curves and calculating elastic modulus and hardness. In addition, the microstructure evolution was adopted using atomic configuration to study the nanoindentation mechanism. This work offers valuable insights into the Cu sinter paste preparation phase for sintering technology.