Charge injection in organic light-emitting diodes: Tunneling into low mobility materials

Journal Article · Tue Oct 01 04:00:00 EDT 1996 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.117530· OSTI ID:385631

Davids, P S; Kogan, S M; Parker, I D; Smith, D L ^[1]

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1. Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

We present device model calculations for the current{endash}voltage ({ital I}{endash}{ital V}) characteristics of organic diodes and compare them with measurements of structures fabricated using MEH-PPV. The measured {ital I}{endash}{ital V} characteristics have a Fowler{endash}Nordheim (FN) functional form, but are more than three orders of magnitude smaller than the calculated FN tunneling current. We find that the low mobility of the organic materials leads to a large backflow of injected carriers into the injecting contact. These results account for the experimental observations and also demonstrate how transport layers in multilayer organic light-emitting diodes can be used to improve carrier injection.

• OSTI ID: 385631
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 15 Vol. 69; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
CHARGE CARRIERS
ELECTROLUMINESCENCE
ELECTRON MOBILITY
LAYERS
LIGHT EMITTING DIODES
POLYMERS
TUNNEL EFFECT