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3D Laser Printing of Diamond-based Composites for Thermal Management Applications
The constant increase of the working frequency of semiconductor-based devices with their miniaturization led to severe overheating, which affect their lifetime and reliability. Hence, thermal management has become a significant concern for the microelectronic area and needs to be addressed. Diamond (D) is known to be an excellent material for thermal dissipation as it possesses one of the highest thermal conductivity (TC) of any natural material and has a high electrical resistivity. D can cool electronic chips in two ways. When used in the form of a film, D acts as a heat spreader. When utilized in powder-form, Ds can be introduced into metals to enhance their TC and bring dimensional stability at elevated temperatures. The resulting metal/D composite materials are thus, excellent component to form heat sinks. Naturally, the thermal performances of heat sinks are closely related to their surface area. Although the attractiveness of D-based materials in term of thermal performance, they often exhibit simple geometry mostly due to the complexity of machining D-based materials into intricated designs. In this study, the laser 3D printing of copper/D composite materials is proposed to fabricate highly complex Cu/D structures which could remodel their applications. Before additively manufactured Cu/D composite materials, several challenges need to be addressed. First, the additive manufacturing of pure Cu is optimized and characterized. Then, due to a lack of a chemical affinity between Cu and D, the Cu-D interfacial zone is introduced in the composite material. Later, a molten salt coating process is studied to produced graded and multilayer coating of oxide/carbide and carbide/carbide, respectively, on carbon materials. Next, the additive manufacturing of highly sophisticated Cu/D composite structures is presented. Finally, the deposition of D films is performed by laser-assisted combustion flame. The effects of introducing ultraviolet lasers into the combustion flame are characterized in terms of chemical reaction and D film quality and growth rate.
Condensed matter physics|Inorganic chemistry
Constantin, Loic Benoit, "3D Laser Printing of Diamond-based Composites for Thermal Management Applications" (2020). ETD collection for University of Nebraska - Lincoln. AAI28026176.