Thermal and non-thermal saturation effects in the output characteristic of UV-to-violet emitting (AlGaIn)N LEDs
- 1 April 2007
- journal article
- Published by Wiley in Physica Status Solidi (a)
- Vol. 204 (4), 1018-1024
- https://doi.org/10.1002/pssa.200674112
Abstract
UV‐to‐violet emitting (AlGaIn)N LEDs have been investigated with respect to the temperature‐dependence of the output power characteristics and non‐thermal rollover of the quantum efficiency at higher current densities. Analyzing MOVPE grown LED chips emitting in the 377 to 428 nm wavelength interval, the temperature sensitivity was found to increase and the output power to decrease with decreasing wavelength λ for λ < 400 nm. A sub‐linear increase of the output power with increasing injection current even in the absence of any thermal effects, i.e. a non‐thermal rollover of the quantum efficiency, was observed to be most pronounced for longer wavelength LEDs (λ > 400 nm). Furthermore, the transient temperature rise after turn‐on has been studied for differently packaged 377 nm LEDs, for which the temperature coefficient of the output power has been found to be particularly large.Keywords
This publication has 14 references indexed in Scilit:
- Junction and carrier temperature measurements in deep-ultraviolet light-emitting diodes using three different methodsApplied Physics Letters, 2005
- Determination of junction temperature and thermal resistance in the GaN‐based LEDs using direct temperature measurementphysica status solidi (c), 2004
- III-N based short-wavelength LEDs, LUCO-LEDs, and lasersphysica status solidi (a), 2004
- High brightness LEDs for general lighting applications Using the new ThinGaN™-Technologyphysica status solidi (a), 2004
- Importance of Nonradiative Recombination Processes in Violet/UV InGaN Light Emitting Diodesphysica status solidi (a), 2002
- High-Power III-Nitride Emitters for Solid-State Lightingphysica status solidi (a), 2002
- 324 nm Light Emitting Diodes with Milliwatt PowersJapanese Journal of Applied Physics, 2002
- In situ temperature measurements via ruby R lines of sapphire substrate based InGaN light emitting diodes during operationJournal of Applied Physics, 2001
- The effects of indium concentration and well-thickness on the mechanisms of radiative recombination in InxGa1−xN quantum wellsMRS Internet Journal of Nitride Semiconductor Research, 2000
- Ohmic Heating of InGaN LEDs during Operation: Determination of the Junction Temperature and Its Influence on Device Performancephysica status solidi (a), 1999