Thermal characterization of high power LED with ceramic particles filled thermal paste for effective heat dissipation

• Thermal grease was filled with AlN and BN particles of different sizes.
• The effects of milling time on particle sizes and surface structure were investigated.
• The differences of SEM micrograph of the milled powder were discussed.
• Thermal transient measurement were used to identify the influences of AlN and BN particles.
• The effect of optical power in thermal resistance was discussed.

The next generation packaging materials are expected to possess high heat dissipation capability. Understanding the needs for betterment in the field of thermal management, the present study aims at investigating the package level analysis on a high power LED. In this study, commercially available thermal paste was heavily filled with ceramic particles of aluminium nitride (AlN) and boron nitride (BN) in order to enhance the heat dissipation of the device. Different particle sizes of AlN and BN fillers were incorporated homogenously into the thermal paste and applied as a thermal interface material (TIM) for an effective system level analysis employing thermal transient measurement. It was found that AlN TIM achieve less LED junction temperature by a difference of 2.20 °C compared to BN filled TIM. Furthermore, among D50 = 1170 nm, 813 nm and 758 nm, the AlN at D50 = 1170 nm was found to exhibit the lowest junction temperature of 38.49 °C and the lowest total thermal resistance of 11.33 K/W compared to the other two fillers.