"JOURNAL OF RADIO ELECTRONICS" (Zhurnal Radioelektroniki ISSN 1684-1719, N 9, 2018

contents of issue      DOI  10.30898/1684-1719.2018.9.7     full text in Russian (pdf)  

Dynamic characteristics and quantum efficiency of separate spectral components of the electroluminescence spectrum of InGaN LEDs


I. V. Frolov1, O. A. Radaev1,2, V. A. Sergeev1,2

1Ulyanovsk Branch of Kotel’nikov Institute of Radio-Engineering and Electronics of Russian Academy of Sciences, Goncharov st. 48/2, Ulyanovsk 432071, Russia

2Ulyanovsk State Technical University, Severnyy Venec 32, Ulyanovsk 432027, Russia


The paper is received on September 3, 2018


Abstract. The description of the automated hardware and software complex for measuring the boundary frequency of modulation and determining the quantum efficiency of separate spectral components of the full electroluminescence spectrum of light-emitting diodes is presented. The principle of operation of the complex is based on the accumulation of the measuring results of the LED emission spectrum  from the output of the OceanOptics USB2000+ spectrometer when passing through the LED current pulses of a given amplitude and frequency and subsequent allocation of individual spectral components from the total spectrum. The complex is tested on commercial green InGaN LEDs with quantum wells. Dependences of the boundary frequency of modulation and the level of the spectral components on the amplitude of the current pulses are given. Estimations of the lifetime of charge carriers for radiative and nonradiative recombination in the current range of 10 μA–10 mA are obtained. It is established that the lifetime of charge carriers in nonradiative recombination decreases monotonically over the entire range of currents, and the lifetime of charge carriers in radiative recombination forming the long-wavelength wing of the electroluminescence spectrum reaches saturation in the region of high currents, which is explained by saturation of the levels of radiative recombination in quantum wells with growth injection current. The developed hardware and software and technique of assessment of recombination parameters of heterojunction LEDs with quantum wells can be used as for the purposes of diagnostics of quality of LEDs, and in case of working off of constructional technology solutions during creation of new light-emitting structures.

Key words: LED, electroluminescence, spectral quantum efficiency, boundary frequency of modulation, radiative recombination, nonradiative recombination, lifetime of charge carriers.


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For citation:
I. V. Frolov, O. A. Radaev, V. A. Sergeev. Dynamic characteristics and quantum efficiency of separate spectral components of the electroluminescence spectrum of InGaN LEDs. Zhurnal Radioelektroniki - Journal of Radio Electronics. 2018. No. 9. Available at http://jre.cplire.ru/jre/sep18/7/text.pdf

DOI  10.30898/1684-1719.2018.9.7