Luminescence Decay Times of PdOEP:PVK OLEDs Fabricated in Controlled O(2) and H(2)O Environments

TitleLuminescence Decay Times of PdOEP:PVK OLEDs Fabricated in Controlled O(2) and H(2)O Environments
Publication TypeJournal Article
Year of Publication2011
AuthorsCui WP, Liu R, Smith A, Shinar J, Shinar R
Journal TitleOrganic Semiconductors in Sensors and Bioelectronics IV
Volume8118
Pages81180v
Date Published08/24
ISBN Number0277-786X
Accession NumberISI:000297625300011
Keywordsdegradation mechanisms, DIODES, electroluminescence decay time, films, LIGHT-EMITTING DEVICES, o(2) sensor, OLED, oxygen, photoluminescence decay time, TRIPLET-TRIPLET ANNIHILATION
Abstract

Residual levels of O(2) in OLEDs and their relation to device performance were evaluated by measuring (i) the photoluminescence (PL) decay time (following pulsed UV LED excitation) of the O2 sensing dye Pd octaethylporphyrin (PdOEP) doped in the active OLED layer poly(N-vinyl carbazole) (PVK) and (ii) the electroluminescence (EL) decay time (following a bias pulse) of glass/ITO/PEDOT: PSS/6 wt.% PdOEP: PVK/CsF/Al OLEDs. The active layer was prepared under various conditions of exposure to controlled O2 levels and relative humidity. PdOEP was used successfully for monitoring exposure of PdOEP: PVK to low levels of oxygen and shortened device PL decay times often indicated device deterioration. The PL decay time at various applied voltages and the EL decay time at various current densities were monitored to evaluate degradation processes related to oxygen and other bimolecular quenching phenomena.

URL<Go to ISI>://000297625300011http://spiedigitallibrary.org/proceedings/resource/2/psisdg/8118/1/81180V_1?isAuthorized=no
DOI10.1117/12.894709
Alternate JournalProc Spie