Properties Of Epoxy Composites Adhesive Film With High Thermal Conductivity And Insulation

As a kind of important thermal management materials, thermal insulation polymer compositesare widely used in the fields of high-frequency microelectronic devices. It has play an important rolein the normal operation and long-life components of microelectronic devices.In this thesis, the epoxy composites adhesive film were designed by using ANSYS software andprepared by the mixture of epoxy resin matrix and thermally conductive fillers, including hexagonalboron nitride (h-BN)and aluminum nitride (AlN). A silane coupling agent (KH550) was used tomodified the fillers to improve the interface interaction between fillers and EP and the EP wasstrengthened and toughened by nitrile rubber (CTBN), which can improves the wettability,as well asthe ease of film processing.Epoxy composites adhesive films prepared by the mixture of epoxy resin matrix and AlN fillerwere had been investigated. By using ANSYS software to simulate the thermal conductivity of theepoxy composites filled by the random-arranged AlN particle, the effect of particle content and sizegradation on the thermal conductivity of the composite material were studied, as well as the optimumfiller formulation solutions were obtained, and finally the validity of thermal simulation results wasverified by experiments. It was found that the thermal conductivity of film was increased with theincremental filler fraction, furthermore, the thermal conductivity increases first and then decreasedwith the increasing portion of smaller particles under the same overall filler addition. When thecoarser and finer particle size ratio is4:6, under the60wt%overall AlN filling content, the thermalconductivity of film is as high as1.373W/m·K,7times higher than the EP matrix. The dielectricproperties decreases with the increasing filler fraction, but the dielectric constants are less than7,which meet the application demands very well. The peeling strength increases first and thendecreases with increasing filler. The TG analysis shows the film has a small change in mass within350℃.Furthermore, the influences of the amount of thermally conductive fillers BN and double sizedfilling on BN/EP composite adhesive film were investigated. It was found that the thermalconductivity of the insulating film has little change at lower filler content, since particles beingwrapped. Thereafter, thermal conductive network was formed with the increasing BN fraction, andthe thermal conductivity increased as well. With the40wt%h-BN addtion, the maximum thermalconductivity of composite materials was achieved as0.876W/m·K, which is superior to the reported value0.5-0.8W/m·K. Under a fixed overall BN loading, the Sizes of the selected finer and coarserparticle are disparity, so the finer ones were substantially not contribute to the thermal conductivity,and therefore in order to obtain better thermal insulation film, we needs to optimize the packing size.The permittivity of the BN/EP was below7under the1MHZ, which can fit the material insulationperformance requirements; the Peeling strength was greater than1.5N/mm. The TG analysisindicated that the specimen is with an enhanced thermal stability.