The application of molybdenum foil as a substrate material
As integrated circuits and power modules continue to evolve towards higher power density, miniaturization and high-frequency operation, traditional substrate materials are gradually unable to meet the demands. Molybdenum foil, due to its excellent properties, has become the ideal choice.
The thermal conductivity of molybdenum strip is 138 W/(m·K), which is much higher than that of traditional ceramic substrates; the thermal expansion coefficient is approximately 4.8×10⁻⁶/K. The molybdenum foil is similar to semiconductor materials such as silicon and silicon carbide, which can reduce thermal stress; the melting point is 2623°C, with outstanding high-temperature stability. Moreover, the molybdenum strip has good mechanical strength and processing performance, and can be made into ultra-thin and highly flat substrates.
Molybdenum foil is widely used in multiple fields: In high-power integrated circuits, it can be used as a thermal diffusion layer and as an intermediate layer for packaging, solving the heat dissipation problem of high-end computing chips; in power modules, the "molybdenum - ceramic - molybdenum" structure can replace traditional technologies, and power modules with molybdenum foil substrates have a lifespan increase of more than 30% compared to traditional structures; in LED and radio frequency devices, it can replace aluminum or copper as the substrate, reducing the failure of solder joints caused by thermal mismatch, and its high electromagnetic shielding performance is suitable for high-frequency circuits.
The application of molybdenum foil faces challenges such as high cost, difficulty in welding and packaging, and processing difficulties. To address the cost issue, molybdenum-copper or molybdenum-silver composite materials can be used, and the rolling process can be optimized to increase yield. In terms of welding, nickel or gold plating on the surface, and the use of active solder or low-temperature sintered silver can improve reliability. In terms of processing, powder metallurgy combined with rolling process can be utilized to enhance ductility, and new types of molybdenum alloys can be developed to improve mechanical properties, in order to address the brittleness of pure molybdenum and the fragility of ultra-thin foils.
Mosten Alloy can produce molybdenum sheet, molybdenum block, molybdenum foil, molybdenum rod, molybdenum wire, molybdenum processing workpiece according to customer demand.
