Open AccessOutcoupling efficiency enhancement of a bottom-emitting OLED with a visible parylene film
Author(s) -
Akpeko Gasonoo,
Ye-Seul Lee,
Ji-Hyeon Yoon,
Baeksang Sung,
Yoonseuk Choi,
Jonghee Lee,
Jae-Hyun Lee
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.397789
Subject(s) - materials science , oled , parylene , transmittance , xylylene , visible spectrum , chemical vapor deposition , optoelectronics , optics , conformal coating , fabrication , coating , polymer , nanotechnology , layer (electronics) , composite material , medicine , physics , alternative medicine , pathology , polymer chemistry
We have investigated an effective and a single-step chemical vapor deposition (CVD) method to achieve conformal visible poly-dichloro-para-xylylene (parylene C) film for light extraction enhancement in bottom-emitting organic light-emitting diodes (OLEDs) at room temperature. We report that sublimed parylene dimers pyrolyzed between 400 °C and 500 °C resulted in visible parylene films with tunable transmittance and haze, exhibiting light scattering properties due to the formation of uniformly distributed dimer crystals. We achieved a novel conformal visible parylene film with total transmittance and high haze of 79.5% and 93.6%, respectively. It is observed that the outcoupling efficiency of the OLEDs employing the visible parylene film is enhanced up to 45.8%. Additionally, the OLED with the visible parylene light extraction film shows limited angle-dependency of emission spectrum over viewing angles. The single-step room temperature fabrication process of this conformal outcoupling film paves the way to achieving commercial high-performance OLEDs.