Thermal Characterization of LEDs Mounted on Substrates With Converging–Diverging and Diverging–Converging Channels

Thermal management stances a massive threat in solid-state lighting devices. With light-emitting diodes (LEDs) gaining attention for implementation in various applications, it is important to address its thermal issues. Thermal resistance and junction temperature are the critical parameters of LEDs which should be maintained at optimum ranges for its reliable operation. In this paper, novel substrates were proposed to minimize the thermal parameters of LEDs. Aluminum substrates with converging-diverging (CD) and Diverging-converging (DC) geometries were micromilled. Thermal characterization was done using thermal transient method by mounting LED on CD and DC substrates. The thermal performance of proposed substrates was compared with bare aluminum substrate by measuring the thermal resistance and junction temperature of LED. On analysis, DC substrates showed lower thermal resistance and junction temperature compared with the other two substrates due to conjugate heat transfer effect within the channels.