Screen and stencil printed graphene heat spreaders on printed circuit boards for lowering of light emitting diode temperatures
Journal article, 2025
Continuously higher integration levels in (opto-)electronics require new solutions and materials for thermal management of excess heat. Here we investigate the integration of graphene-based heat spreader films with printed circuit board (PCB) assembled, high-power light emitting diodes (LEDs), as used in modern automotive lighting, using industrially highly scalable screen printing and stencil printing of the graphene-based films. We compare screen/stencil printing of graphene heat spreaders on the PCBs from archetypical water- and ester-based inks and characterize the resulting graphene heat spreaders with respect to printing fidelity and resolution, film microstructure, electrical and thermal properties and their performance in lowering LED temperatures during LED operation. Importantly, we use only comparatively low graphene film curing temperatures (150 °C) that are compatible with industrial PCB/surface-mounted-device (SMD) LED integration processes. We find that screen-printed, ester-based graphene heat spreaders result in a modest reduction of LED temperature during operation of on average − 2 K with a maximum reduction of −4 K. Generally, our work establishes the feasibility of scalable screen and stencil printing for integration of graphene films with state-of-the-art PCB/SMD assemblies.
Light emitting diodes
Stencil printing
Graphene
Screen printing
Heat spreaders
Author
Reinhard Kaindl
Joanneum Research Forschungsgesellschaft mbH
David Dergez
ZKW Elektronik GmbH
Tushar Gupta
Vienna University of Technology
Songfeng Pei
University of Chinese Academy of Sciences
Peng Xiang Hou
University of Chinese Academy of Sciences
Jinhong Du
University of Chinese Academy of Sciences
Chang Liu
University of Chinese Academy of Sciences
Bernhard Fickl
Vienna University of Technology
Martin Nastran
Vienna University of Technology
Ya Liu
Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems
Alexander Blümel
Joanneum Research Forschungsgesellschaft mbH
Dominik Eder
Vienna University of Technology
Johan Liu
Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems
Wencai Ren
University of Chinese Academy of Sciences
Paul Hartmann
Joanneum Research Forschungsgesellschaft mbH
Wolfgang Waldhauser
Joanneum Research Forschungsgesellschaft mbH
Dietmar Kieslinger
ZKW Elektronik GmbH
Bernhard C. Bayer
Vienna University of Technology
University of Vienna
Surface and Coatings Technology
0257-8972 (ISSN)
Vol. 517 132821Subject Categories (SSIF 2025)
Other Materials Engineering
DOI
10.1016/j.surfcoat.2025.132821