[PDF]    http://dx.doi.org/10.3952/lithjphys.49115

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 49, 69–74 (2009)


EFFECT OF LONG-TERM AGING ON SERIES RESISTANCE AND JUNCTION CONDUCTIVITY OF HIGH-POWER InGaN LIGHT-EMITTING DIODES
Z. Vaitonis, A. Miasojedovas, A. Novičkovas, S. Sakalauskas, and A. Žukauskas
Institute of Materials Science and Applied Research, Vilnius University, Saulėtekio 9, LT-10222 Vilnius, Lithuania
E-mail: zenonas.vaitonis@ff.vu.lt

Received 12 December 2008; revised 13 March 2009; accepted 19 March 2009

The forward voltage, series resistance, and junction conductivity of commercial high-power InGaN light-emitting diodes (LEDs) were investigated as a function of aging time. A gradual decrease of series resistance with a rate of about –1%/1000 h was revealed in InGaN LEDs within first ~9,600 hours of aging under ordinary conditions (nominal forward current 350 mA, junction temperature 350 K), whereas the characteristic energy of tunnel injection exhibited a decrease with a rate of about –0.1%/1000 h. The observed aging effects were attributed to continuous post-fabrication self-annealing of the p-type cladding layer and to the variation of the localized-state density in the active layer of the LED chips.
Keywords: aging, high-power LED, series resistance, junction conductivity
PACS: 81.40.Cd, 85.60.Bt, 85.60.Jb, 84.37.+q, 73.40.Kp


SENĖJIMO ĮTAKA DIDELĖS GALIOS InGaN ŠVIESOS DIODŲ NUOSEKLIAJAI VARŽAI IR SANDŪROS LAIDUMUI
Z. Vaitonis, A. Miasojedovas, A. Novičkovas, S. Sakalauskas, A. Žukauskas
Vilniaus universiteto Medžiagotyros ir taikomųjų mokslų institutas

Tirti didelės galios šviesos diodų tiesioginės įtampos, nuosekliosios varžos bei sandūros laidumo pokyčiai vykstant senėjimo procesui. Po ~9600 valandų sendinimo normaliomis darbo sąlygomis (tiesioginė srovė 350 mA, sandūros temperatūra apie 350 K), nustatytas dėsningas, –1 % / 1000 val., nuosekliosios varžos mažėjimas ir –0.1 % / 1000 val. tunelinės injekcijos į aktyviąją sritį charakteringos energijos mažėjimas. Pastebėti kitimai gali būti susiję su savaiminiu diodo p sluoksnio atkaitinimu ir lokalizuotųjų būsenų tankio kitimu aktyviojoje srityje.


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