Performance and assembly of silver nanoparticle based thermal interface materials for electronic systems

A composite adhesive based Thermal Interface Material (TIM) is studied for electronics packaging applications. The material contains multiple thermally conductive filler including spheres, flakes, and Low Melting Point (LMP) filler. Dispersed silver nanoparticles were added to the epoxy matrix of the TIM. An experimental study ascertains the resulting materials' performance with a steady-state thermal conductivity test. The thermal impedance of the material is characterized as a function of bond line thickness. An uncertainty analysis is performed. A finite element model is used to evaluate system disturbance errors and system/sensor interaction errors. The model takes into account geometric parameters, boundary conditions, and material properties. A significant decrease in the thermal impedance of the material at high bondline thicknesses is achieved with the addition of silver nanoparticles. This is attributed to partial low temperature sintering of the silver nanoparticles which lowers the inter-particle thermal resistance of the TIM.