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Influence of Electrode Modification by Ar+ Ion Beam Upon Passivation and Electrical Characteristics in Organic Light-Emitting Diodes

Published online by Cambridge University Press:  03 March 2011

Soon Moon Jeong
Affiliation:
Department of Metallurgical Engineering, Yonsei University, Seoul 120-749, Korea
Won Hoi Koo
Affiliation:
Department of Metallurgical Engineering, Yonsei University, Seoul 120-749, Korea
Sang Hun Choi
Affiliation:
Department of Metallurgical Engineering, Yonsei University, Seoul 120-749, Korea
Sung Jin Jo
Affiliation:
Department of Metallurgical Engineering, Yonsei University, Seoul 120-749, Korea
Hong Koo Baik*
Affiliation:
Department of Metallurgical Engineering, Yonsei University, Seoul 120-749, Korea
Se-Jong Lee
Affiliation:
Department of Materials Engineering, Kyungsung University, Busan 608-736, Korea
Kie Moon Song
Affiliation:
Department of Applied Physics, Konkuk University, Chungju 380-701, Korea
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Ion-beam-assisted deposition (IBAD) was used for cathode preparation in organic light-emitting diodes to fabricate dense electrode. Dark spot growth rate was decreased by employing the IBAD process due to a highly packed aluminum structure inhibiting the permeation of H2O and O2. However, undesirable leakage current was generated because energetic particles of Al assisted by Ar+ ion may damage the organic material resulting in reduction of contact resistance. The decrease of contact resistance in the IBAD device may be caused by large contact area, increase of density of states, and Li diffusion to phenyl-substituted poly-p-phenylene vinylene.

Type
Articles
Copyright
Copyright © Materials Research Society 2004

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