[PDF]    https://doi.org/10.3952/physics.v58i2.3749

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 58, 194–203 (2018)


LOW-FREQUENCY NOISE CHARACTERISTICS OF HIGH-POWER WHITE LED DURING LONG-TERM AGING EXPERIMENT
Justinas Glemža, Jonas Matukas, Sandra Pralgauskaitė, and Vilius Palenskis
Institute of Applied Electrodynamics and Telecommunications, Vilnius University, Saulėtekio 3, 10257 Vilnius, Lithuania
E-mail: justinas.glemza@ff.vu.lt; jonas.matukas@ff.vu.lt; sandra.pralgauskaite@ff.vu.lt; vilius.palenskis@ff.vu.lt
Received 27 October 2017; revised 27 November 2017; accepted 21 June 2018

Low-frequency electrical and optical noise characteristics of a high power white InGaN LED and the cross-correlation coefficient between these fluctuations are investigated during the long-term ageing experiment (28000 h). The analysis of cross-correlation shows that the correlated part of the low-frequency electrical noise, which indicates physical processes in the active area of the LED, varies during the ageing experiment. Two main stages are distinguished considering the rapid changes of the noise characteristics. The initial stage (after the first 1100 h) is followed by the decrease in the noise power at low forward currents and the increase in the light output. The final stage (after 28000 h) is characterized by a strong growth of the low-frequency noise, the decrease of the light output and the increase of the correlated part of electrical and optical fluctuations. These changes mean a failure in the active layer of the LED. The optical output decomposition into two spectral parts, the radiation generated by the LED chip and the radiation generated by the phosphor layer, enables evaluation of the phosphor layer influence on the degradation process of device optical characteristics. Despite the fact that this layer contributes to the variation of the LED chromatic properties, the cross-correlation analysis has shown that the phosphor layer does not act as a possible noise source during the ageing experiment.
Keywords: ageing, cross-correlation coefficient, electrical noise, light-emitting diode, optical noise
PACS: 72.70.+m, 85.60.Jb

DIDELĖS GALIOS BALTOS ŠVIESOS DIODO ŽEMADAŽNIO TRIUKŠMO CHARAKTERISTIKOS ILGALAIKIO SENDINIMO EKSPERIMENTO METU
Justinas Glemža, Jonas Matukas, Sandra Pralgauskaitė, Vilius Palenskis

Vilniaus universiteto Taikomosios elektrodinamikos ir telekomunikacijų institutas, Vilnius, Lietuva

Ilgalaikio sendinimo eksperimento metu (28000 val.) tirtos didelės galios InGaN pagrindu pagaminto baltos šviesos diodo žemadažnio elektrinio ir optinio triukšmo charakteristikos bei jų tarpusavio koreliacijos koeficientas. Koreliacinė analizė rodo, kad koreliuoto žemadažnio elektrinio triukšmo dalis, kuri atspindi fizikinius procesus, vykstančius šviesos diodo aktyviojoje srityje, sendinimo eksperimento metu kinta. Atsižvelgiant į staigius triukšmų charakteristikų pokyčius išskiriami du pagrindiniai etapai. Pradinis etapas (po pirmųjų 1100 val.) yra susijęs su elektrinio triukšmo mažėjimu tekant bandiniu mažoms srovėms ir spinduliuotės galios padidėjimu, o galutinis etapas (po 28000 val.) charakterizuojamas staigiu žemadažnio triukšmo augimu, spinduliuotės galios sumažėjimu ir elektrinio triukšmo koreliuotosios dalies su optiniu triukšmu didėjimu. Tai rodo aktyviosios srities gedimą. Optinio spektro skaidymas į puslaidininkio šviesos diodo lusto spinduliuotę ir perspinduliuotą fosforo sluoksnio leidžia įvertinti fosforo sluoksnio įtaką prietaiso optinių charakteristikų blogėjimui. Nepaisant to, kad šis sluoksnis itin prisideda prie šviesos diodo chromatinių savybių kitimo, tarpusavio koreliacijos koeficiento analizė rodo, kad fosforo sluoksnis sendinimo eksperimento metu nėra triukšmo šaltinis.

References / Nuorodos

[1] M. Yazdan Mehr, W.D. van Driel, and G.Q. Zhang, Accelerated life time testing and optical degradation of remote phosphor plates, Microelectron. Reliab. 54, 1544–1548 (2014),
https://doi.org/10.1016/j.microrel.2014.03.014
[2] M. Meneghini, L.R. Trevisanelloa, F. de Zuania, N. Trivellin, G. Meneghesso, and E. Zanoni, Extensive analysis of the degradation of Phosphor-Converted LEDs, Proc. SPIE 7422, 74220H-1 (2009),
https://doi.org/10.1117/12.826062
[3] A. Jayawardena and N. Narendran, Analysis of electrical parameters of InGaN-based LED packages with aging, Microelectron. Reliab. 66, 22–31 (2016),
https://doi.org/10.1016/j.microrel.2016.09.012
[4] J. Fan, K.-C. Yung, and M. Pecht, Lifetime estimation of high-power white LED using degradation-data-driven method, IEEE Trans. Device Mater. Reliab. 12(2), 470–477 (2012),
https://doi.org/10.1109/TDMR.2012.2190415
[5] M. Yazdan Mehr, W.D. van Driel, and G.Q. Zhang, Reliability and lifetime prediction of remote phosphor plates in solid-state lighting applications using accelerated degradation testing, J. Electron. Mater. 45(1), 444–452 (2016),
https://doi.org/10.1007/s11664-015-4120-y
[6] B.K. Jones, Electrical noise as a reliability indicator in electronic devices and components, IEE Proc. Circ. Dev. Syst. 149, 13–22 (2002),
https://doi.org/10.1049/ip-cds:20020331
[7] L.K.J. Vandamme, Noise as diagnostic tool for quality and reliability of electronic devices, IEEE Trans. Electron Dev. 41, 2176–2187 (1994),
https://doi.org/10.1109/16.333839
[8] S. Bychikhin, D. Poganya, L.K.J. Vandamme, G. Meneghesso, and E. Zanoni, Low-frequency noise sources in as-prepared and aged GaN-based light-emitting diodes, J. Appl. Phys. 97, 123714 (2005),
https://doi.org/10.1063/1.1942628
[9] S. Sawyer, S.L. Rumyantsev, and M.S. Shur, Degradation of AlGaN-based ultraviolet light emitting diodes, Solid State Electron. 52, 968–972 (2008),
https://doi.org/10.1016/j.sse.2008.01.027
[10] V. Palenskis, J. Matukas, S. Pralgauskaitė, and B. Saulys, A detail analysis of electrical and optical fluctuations of green light-emitting diodes by correlation method, Fluct. Noise Lett. 9(2), 179–192 (2010),
https://doi.org/10.1142/S0219477510000149
[11] K.K. Leung, W.K. Fong, and C. Surya, Low-frequency noise in GaN diodes, in: Proceedings of the 21st International Conference on Noise and Fluctuations (IEEE, 2011) pp. 291–296,
https://doi.org/10.1109/ICNF.2011.5994325
[12] I.-H. Lee, A. Y. Polyakov, S.-M. Hwang, N.M. Shmidt, E.I. Shabunina, N.A. Tal'nishnih, N.B. Smirnov, I.V. Shchemerov, R.A. Zinovyev, S.A. Tarelkin, and S.J. Pearton, Degradation-induced low frequency noise and deep traps in GaN/InGaN near-UV LEDs, Appl. Phys. Lett. 111, 062103 (2017),
https://doi.org/10.1063/1.4985190
[13] L. Liu, J. Yang, and G. Wang, The investigation of LED's reliability through highly accelerated stress testing methods, in: 2012 14th International Conference on Electronic Materials and Packaging (EMAP) (IEEE, 2012) pp. 1–3,
https://doi.org/10.1109/EMAP.2012.6507888
[14] V. Palenskis, J. Matukas, and B. Šaulys, A detailed analysis of electrical and optical fluctuations of light-emitting diodes by correlation method, Lith. J. Phys. 49, 453–460 (2009),
https://doi.org/10.3952/lithjphys.49408
[15] V. Palenskis and K. Maknys, Nature of low-frequency noise in homogenous semiconductors, Sci. Rep. 5, 18305 (2015),
https://doi.org/10.1038/srep18305
[16] V. Palenskis, J. Matukas, and S. Pralgauskaitė, Light-emitting diode quality investigation via low-frequency noise characteristics, Solid State Electron. 54(8), 781–786 (2010),
https://doi.org/10.1016/j.sse.2010.04.003
[17] J. Hu, L. Yang, L. Kim, and M.W. Shin, The ageing mechanism of high-power InGaN/GaN light-emitting diodes under electrical stresses, Semicond. Sci. Technol. 22, 1249–1252 (2007),
https://doi.org/10.1088/0268-1242/22/12/001
[18] C.S. McCamy, Correlated color temperature as an explicit function of chromaticity coordinates, Color Res. Appl. 17(2), 142–144 (1992),
https://doi.org/10.1002/col.5080170211
[19] Z. Qin, J. Feng, C. Zhaohui, X. Ling, W. Simin, and L. Sheng, Effect of temperature and moisture on the luminescence properties of silicone filled with YAG phosphor, J. Semicond. 32(1), 012002 (2011),
https://doi.org/10.1088/1674-4926/32/1/012002