Zhurnal Radioelektroniki - Journal of Radio Electronics. eISSN 1684-1719. 2022. 7

Full text in Russian (pdf)

Russian page


DOI: https://doi.org/10.30898/1684-1719.2022.7.6


Diagnostic quality control of LEDs

by thermal characteristics


V.А. Sergeev 1,2. O.A. Radaev 1, I.V. Frolov 1


1 Ulyanovsk Branch of Kotelnikov IRE RAS

432071, Russia, Ulyanovsk, Goncharov st., 48/2

2 Ulyanovsk State Technical University

432027, Russia, Ulyanovsk, Severnyy Venets, 32


The paper was received May 18, 2022.


Abstract. The results of measurements of the current dependences of the thermal resistance of the junction-case of LEDs of various types and manufacturers are presented. It is determined that the thermal resistance increases with increasing current, and for many samples there is a noticeable break in the current dependence of thermal resistance at currents close to the nominal one. It has been experimentally shown that the steepness of the current dependence of the junction-case thermal resistance can be used as a diagnostic parameter that makes it possible to estimate the degree of temperature distribution inhomogeneity. According to the results of tests of red low-power LEDs TLCR5800 under direct current for 8,000 h, a correlation was established between the magnitude of the power drop and the steepness of the current dependence of the junction-case thermal resistance: the correlation coefficient of these values ​​was 0.538. The relative change in thermal resistance during testing is strongly correlated with the absolute value of thermal resistance before testing: the correlation coefficient is -0.685. On the basis of the experimental results obtained, a method for quality control of LEDs was developed by the steepness of the current dependence of the thermal resistance of the junction-case. The developed methods for quality control of LEDs can be recommended for use at the input control of enterprises-manufacturers of LED products.

Key words: LED, thermal resistance, current slope, testing, performance control.

Financing: The work was carried out within the framework of the state task and partially was supported by the Russian Foundation for Basic Research and Ulyanovsk region, project number 19-47-730002.

Corresponding author: Sergeev Vyacheslav Andreevich, sva@ulstu.ru


1) He P., Zhou J., Yin L., Zhang J. The illuminance and temperature distribution degradation of high power GaN LED caused by detachment of multilayer electrode. Optical and Quantum Electronics. 2018. V.50. 458. https://doi.org/10.1007/s11082-018-1706-7

2) De Santi C., Meneghini M., Meneghesso G., Zanoni E. Degradation of InGaN laser diodes caused by temperature- and current-driven diffusion processes. Microelectronics Reliability. 2016. V.64. P.623-626. https://doi.org/10.1016/j.microrel.2016.07.118

3) Fu J., Zhao L., Cao H., Sun X., Sun B., Wang J., Li J. Degradation and corresponding failure mechanism for GaN-based LEDs. AIP Advances. 2016. V.6. P.055219. https://doi.org/10.1063/1.4953056

4) Huang J. Optical degradation mechanisms and accelerated reliability evaluation for LEDs. Doctoral thesis. Delft University of Technology. 2016. https://doi.org/10.4233/uuid:299c48c9-5bc7-4c5a-aab8-1b82696fbb5b

5) Lisik Z., Raj E. Podgórski J. Numerical Model of Current Flow and Thermal Phenomena in Lateral GaN/InGaN LEDs. Electronics. 2021. V.10. P.3127. https://doi.org/10.3390/electronics10243127

6) Sergeev V.A., Khodakov A.M. Thermoelectric Models of High-Power Bipolar Semiconductor Devices. Part II. Nonlinear Model of LEDs. Journal of Communications Technology and Electronics. 2015. V.60. P.1328-1332. https://doi.org/10.1134/S1064226915080161

7) Ma Z., Cao H., Lin S., Li X., Xi X., Li J., Zhao L. Optical and frequency degradation behavior of GaN-based micro-LEDs for visible light communication. Optical Express. 2020. V.28, 27. P.12795-12804 https://doi.org/10.1364/OE.383867

8) Smirnov V.I., Sergeev V.A., Gavrikov A.A. Measurement of the Thermal Impedance of Light-Emitting Diodes and Light-Emitting Diode Matrices. Measurement Techniques. 2017. V.60. P.46-51. https://doi.org/10.1007/s11018-017-1157-8

9) Development of an experimental sample of a hardware-software complex (ES HSC) using pulse-width modulation of heating power for monitoring and analyzing the thermal characteristics of powerful semiconductor emitters: research report (interim). Kotelnikov IRE RAS (Ulyanovsk Branch), supervisor - Sergeev V.A.; performers - Smirnov V.I. et al. Ulyanovsk. 2015. №GR115050610091. 156 p. (In Russian)

10) Sergeev V.A., Hodakov A.M. Nelineynyye teplovyye modeli poluprovodnikovykh priborov [Nonlinear thermal models of semiconductor devices]. Ulyanovsk, UlSTU. 2012. 163 p. (In Russian)

11) Sergeev V.A., Frolov I.V., Shirokov A.A. Degradation of red AlInGaP/GaAs LEDs during testing at different values of the supply current. Proceedings of the International Scientific and Technical Conference INTERMATIC-2015 [INTERMATIC-2015]. Moscow. 2015. V.4. P.228-230. (In Russian)

For citation:

Sergeev V.A., Radaev O.A., Frolov I.V. Diagnostic quality control of LEDs by thermal characteristics. Zhurnal radioelektroniki [Journal of Radio Electronics] [online]. 2022. №7. https://doi.org/10.30898/1684-1719.2022.7.6 (In Russian)