Electrically and Thermally Conductive Adhesives for Automotive Electronics

摘要

Electrical conductive adhesives that provide a stable connection with non-noble metallizations have been discussed. Electrically conductive adhesives provide the benefit of lower processing temperatures as compared to solder pastes. Due to the lead-free drive eutec-tic solder paste will be replaced by higher melting point lead-free solders thus requiring higher reflow temperatures up to 250-260℃. This may damage temperature sensitive components and limit the lifespan of the product. Electrically conductive adhesives with increased adhesion level are capable of forming a low resistance joint with the most critical components that is stable during 85/85 temperature / humidity testing. Under severe test conditions such as 85%RH/85℃, -40℃/+150℃ and +150℃ heat storage, good adhesion retention of these new adhesives is shown. A good model has been developed to simulate the packing density and to calculate the void fraction and of the filler in thermally conductive adhesives. A proper selection of filler morphology can have a large impact on the thermal conductivity. A method to measure interfacial thermal interfacial resistance with photoflash technique is developed. High thermal conductivity does not necessarily mean low overall thermal resistance. A dielectric adhesive with high thermal conductivity and very low interfacial thermal resistance has been developed and ah electrically conductive adhesive with one of the lowest interfacial thermal resistance is available.