Tawfik Wael Z, Lee June Key
Department of Physics, Faculty of Science, Beni-Suef University, Beni-Suef 62511, Egypt.
Department of Materials Science and Engineering, and Optoelectronics Convergence Research Center, Chonnam National University, Gwangju 500-757, Korea.
J Nanosci Nanotechnol. 2018 Mar 1;18(3):1772-1776. doi: 10.1166/jnn.2018.14942.
The influence of temperature on the characteristics of a GaN-based 460-nm light-emitting diode (LED) prepared on sapphire substrate was simulated using the SiLENSe and SpeCLED software programs. High temperatures impose negative effects on the performance of GaN-based LEDs. As the temperature increases, electrons acquire higher thermal energies, and therefore LEDs may suffer more from high-current loss mechanisms, which in turn causes a reduction in the radiative recombination rate in the active region. The internal quantum efficiency was reduced by about 24% at a current density of 35 A/cm2, and the electroluminescence spectral peak wavelength was redshifted. The LED operated at 260 K and exhibited its highest light output power of ~317.5 mW at a maximum injection current of 350 mA, compared to 212.2 mW for an LED operated at 400 K. However, increasing temperature does not cause a droop in efficiency under high injection conditions. The peak efficiency at 1 mA of injection current decreases more rapidly by ~15% with increasing temperature from 260 to 400 K than the efficiency at high injection current of 350 mA by ~11%.
使用SiLENSe和SpeCLED软件程序模拟了温度对在蓝宝石衬底上制备的基于GaN的460纳米发光二极管（LED）特性的影响。高温对基于GaN的LED性能产生负面影响。随着温度升高，电子获得更高的热能，因此LED可能更容易受到大电流损耗机制的影响，这反过来又会导致有源区辐射复合率降低。在电流密度为35 A/cm2时，内部量子效率降低了约24%，电致发光光谱峰值波长发生红移。该LED在260 K下工作，在350 mA的最大注入电流下表现出最高光输出功率约为317.5 mW，而在400 K下工作的LED的光输出功率为212.2 mW。然而，在高注入条件下，温度升高不会导致效率下降。注入电流为1 mA时的峰值效率随着温度从260 K升高到400 K下降得更快，约为15%，而注入电流为350 mA时的效率下降约为11%。
