Abstract
We developed organic light-emitting diodes (OLEDs) with nanopatterned current flow regions using electron-beam lithography with the aim of suppressing singlet-polaron annihilation (SPA). Nanopatterns composed of lines and circles were used in the current flow regions of nano-line and nano-dot OLEDs, respectively. Excitons partially escape from the current flow regions where SPA takes place. As such, current densities where external quantum efficiencies were half of their initial values (J0) increased as line width and circle diameter were decreased to close to the exciton diffusion length. Circles were more efficient at enhancing exciton escape and increasing J0 than lines. The J0 increase in the nano-dot OLEDs containing nanopatterned circles with a diameter of 50nm was approximately 41-fold that of a conventional OLED with a current flow region of 4mm2. The dependence of J0 on the size and shape of the nanopatterns was well explained by an SPA model that considered exciton diffusion. Nanopatterning of OLEDs is a feasible method of obtaining large J0.
| Original language | English |
|---|---|
| Article number | 155501 |
| Journal | Journal of Applied Physics |
| Volume | 118 |
| Issue number | 15 |
| DOIs | |
| Publication status | Published - 2015 Oct 21 |
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ASJC Scopus subject areas
- Physics and Astronomy(all)
Cite this
Suppression of external quantum efficiency roll-off of nanopatterned organic-light emitting diodes at high current densities. / Kuwae, Hiroyuki; Nitta, Atsushi; Yoshida, Kou; Kasahara, Takashi; Matsushima, Toshinori; Inoue, Munetomo; Shoji, Shuichi; Mizuno, Jun; Adachi, Chihaya.
In: Journal of Applied Physics, Vol. 118, No. 15, 155501, 21.10.2015.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Suppression of external quantum efficiency roll-off of nanopatterned organic-light emitting diodes at high current densities
AU - Kuwae, Hiroyuki
AU - Nitta, Atsushi
AU - Yoshida, Kou
AU - Kasahara, Takashi
AU - Matsushima, Toshinori
AU - Inoue, Munetomo
AU - Shoji, Shuichi
AU - Mizuno, Jun
AU - Adachi, Chihaya
PY - 2015/10/21
Y1 - 2015/10/21
N2 - We developed organic light-emitting diodes (OLEDs) with nanopatterned current flow regions using electron-beam lithography with the aim of suppressing singlet-polaron annihilation (SPA). Nanopatterns composed of lines and circles were used in the current flow regions of nano-line and nano-dot OLEDs, respectively. Excitons partially escape from the current flow regions where SPA takes place. As such, current densities where external quantum efficiencies were half of their initial values (J0) increased as line width and circle diameter were decreased to close to the exciton diffusion length. Circles were more efficient at enhancing exciton escape and increasing J0 than lines. The J0 increase in the nano-dot OLEDs containing nanopatterned circles with a diameter of 50nm was approximately 41-fold that of a conventional OLED with a current flow region of 4mm2. The dependence of J0 on the size and shape of the nanopatterns was well explained by an SPA model that considered exciton diffusion. Nanopatterning of OLEDs is a feasible method of obtaining large J0.
AB - We developed organic light-emitting diodes (OLEDs) with nanopatterned current flow regions using electron-beam lithography with the aim of suppressing singlet-polaron annihilation (SPA). Nanopatterns composed of lines and circles were used in the current flow regions of nano-line and nano-dot OLEDs, respectively. Excitons partially escape from the current flow regions where SPA takes place. As such, current densities where external quantum efficiencies were half of their initial values (J0) increased as line width and circle diameter were decreased to close to the exciton diffusion length. Circles were more efficient at enhancing exciton escape and increasing J0 than lines. The J0 increase in the nano-dot OLEDs containing nanopatterned circles with a diameter of 50nm was approximately 41-fold that of a conventional OLED with a current flow region of 4mm2. The dependence of J0 on the size and shape of the nanopatterns was well explained by an SPA model that considered exciton diffusion. Nanopatterning of OLEDs is a feasible method of obtaining large J0.
UR - http://www.scopus.com/inward/record.url?scp=84945156099&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84945156099&partnerID=8YFLogxK
U2 - 10.1063/1.4932139
DO - 10.1063/1.4932139
M3 - Article
VL - 118
JO - Journal of Applied Physics
JF - Journal of Applied Physics
SN - 0021-8979
IS - 15
M1 - 155501
ER -