A facile route to efficient, low-cost flexible organic light-emitting diodes: utilizing the high refractive index and built-in scattering properties of industrial-grade PEN substrates

Eunhye Kim; Hyunsu Cho; Kyoohyun Kim; Tae-Wook Koh; Jin Chung; Jonghee Lee; YongKeun Park; Seunghyup Yoo

doi:10.1002/adma.201404862

A facile route to efficient, low-cost flexible organic light-emitting diodes: utilizing the high refractive index and built-in scattering properties of industrial-grade PEN substrates

Adv Mater. 2015 Mar 4;27(9):1624-31. doi: 10.1002/adma.201404862. Epub 2015 Jan 21.

Authors

Eunhye Kim¹, Hyunsu Cho, Kyoohyun Kim, Tae-Wook Koh, Jin Chung, Jonghee Lee, YongKeun Park, Seunghyup Yoo

Affiliation

¹ Department of Electrical Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305 - 701, Republic of Korea.

PMID: 25645389
DOI: 10.1002/adma.201404862

Abstract

An industrial-grade polyethylene naphthalate (PEN) substrate is explored as a simple, cost-effective platform for high-efficiency organic light-emitting diodes (OLEDs). Its high refractive index, combined with the built-in scattering properties inherent to the industrial-grade version, allows for a significant enhancement in outcoupling without any extra structuring or special optical elements. Flexible, color-stable OLEDs with efficiency close to 100 lm W(-1) are demonstrated.

Keywords: bulk scattering; high-refractive-index substrates; light extraction; organic light-emitting diodes (OLEDs); polyethylene naphthalate (PEN).