Heat transfer in high-power LED with thermally conductive particle-filled epoxy composite as thermal interface material for system-level analysis

This paper elucidates the thermal behaviour of an LED employing different particles filled epoxy as thermal interface material (TIM) for enhanced heat dissipation. Highly thermal conductive metal filler of aluminium (Al) and ceramic fillers of aluminium nitride (AlN) and aluminium oxide (Al₂O₃) were incorporated in bisphenol A diglycidylether (DGEBA) epoxy resin to identify the effect of the filler materials as TIM on the thermal performance of high power LEDs. From the thermal transient analysis of a 3W warm white LED, it was observed that the Al filled composite exhibits the lowest junction temperature of 38.3 °C compared to the other two fillers. The total thermal resistance of the package with AlN filled composite and Al₂O₃ filled composite were 13.77 and 15.50K/W respectively. This paper too suggests that the total thermal resistance of the LED package increases when the particle size of the fillers decrease.