Additive Manufacturing of 3D Circuit Carriers with Improved Thermal Conductivity

Abstract

The ongoing demand for more powerful electronic assemblies requires the development of more flexible systems with substrates showing improved thermal and electrical properties. In this regard, fiber-filled polymers processed by Additive Manufacturing technologies are promising. While previous work rather focuses on the material and mechanical aspects of filled polymers and 3D printing, this work proposes an innovative approach to manufacture electronic assemblies additively using Fused Filament Fabrication with glass fiber-filled polymers to create 3D substrates and using digital printing technologies to create electrically conductive structures on the manufactured specimens. For this reason, a reduction of substrate surface roughness through systematic optimization of parameter configuration is necessary to print constant conductive lines subsequently. By this means, 3D circuit carriers for electronic assemblies with improved thermal conductivity can be produced completely additively. Surface roughness of ${\mathrm Ra} = 2.6 \mu{\mathrm m}$ and ${\mathrm Rz} = 42.0 \mu{\mathrm m}$ was achieved in this work, and the printed lines were qualified in optical, electrical, and mechanical regard.