TITLE

Light- and ion-gauge-induced space charges in tris-(8-hydroxyquinolate) aluminum-based organic light-emitting diodes

AUTHOR(S)
Noguchi, Yutaka; Sato, Naoki; Miyazaki, Yukimasa; Ishii, Hisao
PUB. DATE
April 2010
SOURCE
Applied Physics Letters;4/5/2010, Vol. 96 Issue 14, p143305
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We report space charge formation in tris-(8-hydroxyquinolate) aluminum (Alq3)-based organic light-emitting diodes induced by light irradiation and ion-gauge (IG) operation during device fabrication. An analysis of the capacitance-voltage curves of the light-treated devices reveals the presence of uniformly distributed negative space charges in the Alq3 layer. Spatial inhomogeneity of the orientation polarization as well as electrons trapped in the Alq3 film can be the origin of the negative space charge. We also found that positively charged species can be included in the device due to IG operation.
ACCESSION #
49071230

 

Related Articles

  • AlGaInP/mirror/Si light-emitting diodes with vertical electrodes by wafer bonding. Horng, R. H.; Huang, S. H.; Wuu, D. S.; Chiu, C. Y. // Applied Physics Letters;6/9/2003, Vol. 82 Issue 23, p4011 

    In a previous study, we reported a highly efficient AlGaInP light-emitting diode (LED) with a (Au/AuBe/SiO[SUB2]/Si mirror substrate (MS) fabricated by wafer bonding, where a planar electrode structure is used. In view of the more efficient epilayer area utilized, AlGaInP/mirror/barrier/Si LEDs...

  • Light degradation and voltage drift in polymer light-emitting diodes. Silvestre, G. C. M.; Johnson, M. T.; Giraldo, A.; Shannon, J. M. // Applied Physics Letters;3/12/2001, Vol. 78 Issue 11, p1619 

    It is shown that the voltage drift and light degradation in polymer light-emitting diodes are related and can be explained by the formation of traps and the modification of the space charge in the bulk of the polymer. The energy released by nonradiative carrier recombination is believed to be...

  • Charge injection versus space-charge-limited current in organic light-emitting diodes. Arkhipov, V.I.; von Seggern, H.; Emelianova, E.V. // Applied Physics Letters;12/15/2003, Vol. 83 Issue 24, p5074 

    A unified model of hopping carrier injection and space-charge-limited current (SCLC) in disordered organic materials is formulated. It is shown that, contrary to what one would intuitively expect, a metal contact with the injection barrier as high as 1 eV can be still an Ohmic contact at low...

  • Optical detection of charge carriers in multilayer organic light-emitting diodes: Experiment and theory. Book, K.; Nikitenko, V. R.; Ba¨ssler, H.; Elschner, A. // Journal of Applied Physics;3/1/2001, Vol. 89 Issue 5, p2690 

    We have investigated a multilayer organic light-emitting diode with 1,3,5-tris (N,N-bis-(4-methoxyphenyl)aminophenyl)-benzene acting as the hole transporting layer (HTL) and tris (8-hydroxy-quinolinolato) aluminum (Alq[sub 3]) as the electron transporting layer. Positive charge carriers in the...

  • High efficiency, high modulation bandwidth (Ga,Al)As:Te,Zn light-emitting diodes with graded band gap. Leibenzeder, S.; Rühle, W.; Hoffmann, L.; Weyrich, C. // Applied Physics Letters;5/15/1985, Vol. 46 Issue 10, p978 

    A new (Ga,Al)As light-emitting diode (λmax =660–880 nm) is presented which has several advantages: simple processing, high external quantum efficiencies (up to 12%), and short decay times (down to 12 ns). The importance of photon recycling and reduced self-absorption in the graded band...

  • High performance AlGaInP visible light-emitting diodes. Kuo, C. P.; Fletcher, R. M.; Osentowski, T. D.; Lardizabal, M. C.; Craford, M. G.; Robbins, V. M. // Applied Physics Letters;12/31/1990, Vol. 57 Issue 27, p2937 

    The performance of surface-emitting visible AlGaInP light-emitting diodes (LEDs) is described. The devices have external quantum efficiencies greater than 2% and luminous efficiencies of 20 lm/A in the yellow (590 nm) spectral region. This performance is roughly ten times better than existing...

  • 1.4x efficiency improvement in transparent-substrate... Gardner, N.F.; Chui, H.C.; Chen, E.I.; Krames, M.R.; Huang, J.-W.; Kish, F.A.; Kocot, C.P.; Tan, T.S.; Moll, N. // Applied Physics Letters;4/12/1999, Vol. 74 Issue 15, p2230 

    Demonstrates the improvements in the external quantum efficiency and luminous efficiency of transparent-substrate [Al[sub x]Ga[sub 1-x]][sub 0.5]In[sub 0.5]P/GaP light-emitting diodes. Improvements accomplished through reducing the thickness of the active layer and increasing the internal...

  • Time-resolved electroluminescence of AlGaN-based light-emitting diodes with emission at 285 nm. Shatalov, M.; Chitnis, A.; Mandavilli, V.; Pachipulusu, R.; Zhang, J. P.; Adivarahan, V.; Wu, S.; Simin, G.; Khan, M. Asif; Tamulaitis, G.; Sereika, A.; Yilmaz, I.; Shur, M. S.; Gaska, R. // Applied Physics Letters;1/13/2003, Vol. 82 Issue 2, p167 

    We present a study on the time evolution of the electreluminescence (EL) spectra of AlGaN-based deep ultraviolet light-emitting diodes (LEDs) under pulsed current pumping. The EL spectra peaks at 285 nm and 330 nm are found to result from recombination involving band-to-band and free carriers to...

  • Low-temperature operation of AlGaN single-quantum-well light-emitting diodes with deep ultraviolet emission at 285 nm. Chitnis, A.; Pachipulusu, R.; Mandavilli, V.; Shatalov, M.; Kuokstis, E.; Zhang, J. P.; Adivarahan, V.; Wu, S.; Simin, G.; Asif Khan, M. // Applied Physics Letters;10/14/2002, Vol. 81 Issue 16, p2938 

    We present a study of the electrical and optical characteristics of 285 nm emission deep ultraviolet light-emitting diodes (LED) at temperatures from 10 to 300 K. At low bias, our data show the tunneling carrier transport to be the dominant conduction mechanism. The room-temperature performance...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics