Study of organic light-emitting devices with 5,6,11,12-tetraphenylnaphthacene (rubrene)-doped hole transport layer

Hany Aziz; Zoran D. Popovic

doi:10.1117/12.454857

3 March 2003 Study of organic light emitting devices with 5,6,11,12-tetraphenylnaphthacene (rubrene)-doped hole transport layer

Hany Aziz, Zoran D. Popovic

Author Affiliations +

Proceedings Volume 4800, Organic Light-Emitting Materials and Devices VI; (2003) https://doi.org/10.1117/12.454857
Event: International Symposium on Optical Science and Technology, 2002, Seattle, WA, United States

Abstract

Doping the hole transport layer (HTL) of organic light emitting devices (OLEDs) was found to increase device operational stability. To this effect, the role of 5,6,11,12-tetraphenylnaphthacene (rubrene), a widely dopant for HTLs, in increasing OLED stability has been widely investigated. However, significant disagreements between various explanations for the increased stability, ranging from rubrene being a charge injection promoter, to its being a charge trap, still exist. We conducted an in-depth study on the influence of rubrene doping of HTL on device stability. The study was carried out on OLEDs of structure: indium-tin-oxide (ITO) anode/N,N'-di(naphthalene-1-yl)-N,N'-diphenyl-benzidine (NPB) HTL / tris(8-hydroxyquinoline) aluminum (AlQ₃) electron transport layer / Mg:Ag cathode, in which different portions of the HTL were doped with rubrene. Compared to undoped devices, stability of OLEDs in which HTL doping was limited to only a thin interfacial layer at either the ITO or AlQ₃ interface was essentially the same, whereas, stability of OLEDs in which a substantial portion of the HTL was doped was about an order of magnitude higher, and approached that of devices where the whole HTL was doped. In addition, for a fixed thickness of the doped portion, device stability was found to be essentially independent of the thickness of the undoped portion. The results demonstrate that increasing OLEDs stability by means of doping the HTL is associated with changes in bulk HTL hole transport properties rather than interfacial properties, and is consistent with OLED degradation mechanism based on instability of cationic AlQ₃ species.

Citation Download Citation

Hany Aziz and Zoran D. Popovic "Study of organic light emitting devices with 5,6,11,12-tetraphenylnaphthacene (rubrene)-doped hole transport layer", Proc. SPIE 4800, Organic Light-Emitting Materials and Devices VI, (3 March 2003); https://doi.org/10.1117/12.454857

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