Screen-Printed Sacrificial Structures For High-Thermal-Conductivity Copper-Diamond Heat Sinks

Abstract

High-power electronic systems increasingly require thermal management solutions that combine superior heat transport with application-specific cooling geometries. This work presents a manufacturing concept for producing complex Cu-diamond heat sinks with thermal conductivities up to 650 W|(m·K). The approach combines additive fabrication of sacrificial Al2O3 molds by additive screen printing with GelCasting, thermal treatment, and Spark Plasma Sintering. The sacrificial structures enable the fabrication of intricate cooling architectures that are difficult or impossible to realize using conventional machining of plates, rods, or tubes. Complex pin-fin heat sinks with varying aspect ratios were successfully manufactured and accurately reproduced the original CAD geometries. After optimization of the sintering conditions, thermal conductivities comparable to directly consolidated reference materials were achieved. The presented process chain provides a scalable route towards simulation-driven, topology-optimized thermal management components for AI hardware, radar systems, and advanced power electronics.