Influence on temperature distribution of COB deep UV LED due to different packaging density and substrate type

The thermal performance of a deep UV LED package in three different chip on board (COB) substrates was studied by finite element simulation. The relationship between the temperature of each component in different COB substrates and the packaging density of the deep UV LED was analyzed. Having the same size of a 1313 COB substrate, this study indicates that the aluminum substrate can adapt to a 0.38 W/mm² packaging density at a maximum owing to the existence of an insulation layer, which has a low thermal conductivity. However, an alumina ceramic substrate can be adapted to a 0.94 W/mm² packaging density. Aluminum nitride ceramic can meet the demand for a higher packaging density; however, the cost is a key factor which cannot be ignored for large-scale applications. The results of this study provide detailed suggestions for researchers and industrial use for the selection of COB substrates packaged with deep UV LED according to different packaging densities, which have a higher practical application value.