Synergistic effects of copper powder morphology and glass phase thermal behavior on the electrical conductivity of sintered electronic copper paste

Abstract Electronic copper paste, as a key material for fabricating electronic components, exhibits performance that is governed by the synergistic interaction between copper powder morphology and the thermal behavior of the glass phase. This study systematically investigated the sintering behavior of three copper powder morphologies (e.g. spherical, coral-like, and flake) paired with two types of glass powders-barium-zinc-boron glass (MCA1) and high-zinc-boron glass (MCB1)-and their mixture (A1B1). By analyzing the microstructure and conductive properties of the sintered bodies, combined with the thermal characteristics of the glass phases, the matching mechanism between the materials was elucidated. The results indicate that spherical copper powder requires matching with low-viscosity, high-fluidity MCB1 glass to establish a highly connected continuous conductive network. Coral-like copper powder needs to be paired with A1B1 glass, which combines low-temperature fluidity and controlled expansion, to infiltrate and fill its complex pores. Flake copper powder, however, should be matched with high-viscosity, high-hemispherical-point MCA1 glass to obtain structural support and maintain the stability of its two-dimensional conductive network. This study establishes a matching model linking copper powder morphology–sintering requirement with glass thermal behavior-functional response, providing a theoretical basis for the rational design of high-performance electronic copper pastes.