Thermal stability of microscale additively manufactured copper using pulsed electrodeposition

Micro/nanoscale 3D printing of metals is promising for printed electronics and sensors. It is important to evaluate how material properties of the microscale 3D-printed metals change at high temperature, though such studies are currently very limited. Here, we investigate morphological and mechanical property changes in copper interconnects 3D-printed by pulsed electrodeposition process. The results revealed significant surface damage and void formation in printed Cu after annealing at 450 °C. No significant surface damages or voids were observed for printed Cu annealed at 300 °C, however, their strength dropped ~40% from the strength of the as-deposited material (~868 MPa). Such results are important to determine the operation temperature range for interconnects fabricated by microscale 3D printing.