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arXiv · 2005.04496

Thermal tuning of light-emitting diode wavelength as an implication of the Varshni equation

Richard O. Ocaya
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Abstract

In this article, we show that the variation of the wavelength of a non-pumped light-emitting diode (LED) is practically linear with temperature, a novel consequence of Varshni's widely accepted empirical expression. This formula models the bandgap variation for most semiconductors from 0K to their high-temperature limits, subject to fitting parameters. Therefore, we suggest an external thermal mechanism that can be used to tune the wavelength of a constant-current biased LED and also to stabilize its wavelength. Furthermore, we demonstrate the approach on published AlN data and show that the fitting parameters follow trivially. In addition, we suggest a novel method to characterize semiconductors. Finally, we present the results of experimental measurements on several commercial LEDs.

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Richard O. Ocaya. 2020-05-09. Thermal tuning of light-emitting diode wavelength as an implication of the Varshni equation. https://doi.org/10.1016/j.measurement.2020.107910

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