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arXiv · 2107.08793

Impact of die carrier on reliability of power LEDs

Shusmitha Kyatam·Luis N. Alves·Stanislav Maslovski·Joana C. Mendes
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Abstract

High power light emitting diodes (LEDs) suffer from heating effects that have a detrimental impact on the devices characteristics. The use LED carriers with high thermal conductivity promotes the extraction of heat away from the LED junction. Different materials can be used for this purpose, such as alumina, aluminium nitride, and silicon. Diamond has also been gaining momentum for demanding heat management applications. In order to evaluate the impact of the different carriers on the reliability of the devices, the junction temperature of Cree white Xamp XB-D LEDs was obtained with Ansys for various carrier at different LED current levels. The impact of the junction temperature on the LEDs lifetime, emission intensity, footprint and wavelength stability was then evaluated for each carrier based on the datasheet of the devices. The results provide additional knowledge regarding the impact of the carrier on the performance of the LED.

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Shusmitha Kyatam, Luis N. Alves, Stanislav Maslovski, Joana C. Mendes. 2021-07-08. Impact of die carrier on reliability of power LEDs. https://arxiv.org/abs/2107.08793

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