Study on charge carrier recombination zone with ultrathin rubrene layer as probe

Wen Wen; Jungsheng Yu; Yi Li; Lu Li; Yadong Jiang

doi:10.1117/12.831025

21 May 2009 Study on charge carrier recombination zone with ultrathin rubrene layer as probe

Wen Wen, Jungsheng Yu, Yi Li, Lu Li, Yadong Jiang

Proceedings Volume 7282, 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies; 72823B (2009) https://doi.org/10.1117/12.831025
Event: AOMATT 2008 - 4th International Symposium on Advanced Optical Manufacturing, 2008, Chengdu, Chengdu, China

Abstract

The characteristic of charge carrier recombination zone in N,N'-bis-(1-naphthyl)-N,N'-biphenyl-1,1'-biphenyl-4,4'-diamine (NPB) based OLEDs is studied using an ultrathin 5,6,11,12-tetraphenylnaphthacene (rubrene) as a probe. By adjusting the rubrene thickness and location in NPB light-emitting layer, the luminescent spectra and electrical properties of the devices are investigated. The results show that when the thickness ranges from 0.2 to 0.8 nm, the surface morphology of rubrene exists as the discontinuous island-like state locating on the surface of NPB film and seldom affect the electrical characteristics. While the location of rubrene shifted from the interface of NPB/2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) to NPB side, the maximum exciton concentration is found within 2 nm away from the interface, which is the main charge carrier recombination zone. With an optimized structure of indium-tin-oxide (ITO)/NPB (40nm)/rubrene (0.3nm)/NPB (7nm)/BCP (30nm)/Mg:Ag, the device exhibits a turn on voltage as low as 3 V and stable white light. The peaks of EL spectra are located at 431 and 555 nm corresponding to the Commissions Internationale De L'Eclairage (CIE) coordinates of (0.32, 0.32), which are relatively stable under the bias voltage from 5 to 15 V. A maximum luminance of 5630 cd/m² and a maximum power efficiency of 0.6 lm/W is achieved. The balanced spectra are attributed to the stable confining of charge carriers and exciton by the thin emitting layers.

Citation Download Citation

Wen Wen, Jungsheng Yu, Yi Li, Lu Li, and Yadong Jiang "Study on charge carrier recombination zone with ultrathin rubrene layer as probe", Proc. SPIE 7282, 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, 72823B (21 May 2009); https://doi.org/10.1117/12.831025

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
5 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Excitons

Organic light emitting diodes

Molecules

Electroluminescence

Interfaces

Lithium

Atomic force microscopy

Show All Keywords

Keywords/Phrases

Search In:

Publication Years