Open AccessQuantitative allocation of Bragg scattering effects in highly efficient OLEDs fabricated on periodically corrugated substrates
Author(s) -
Cornelius Fuchs,
Tobias Schwab,
Teja Roch,
S. Eckardt,
Andrés Fabián Lasagni,
Simone Hofmann,
Björn Lüssem,
Lars MüllerMeskamp,
Karl Leo,
Malte C. Gather,
Reinhard Scholz
Publication year - 2013
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.21.016319
Subject(s) - oled , materials science , optics , scattering , optoelectronics , light scattering , diode , fabrication , electrode , layer (electronics) , nanotechnology , physics , medicine , alternative medicine , pathology , quantum mechanics
Bragg scattering effects in bottom-emitting organic light-emitting diodes (OLEDs) grown on corrugated aluminum-doped zinc oxide electrodes are analyzed. Periodic corrugation is introduced by structuring the oxide electrode via UV laser ablation, a process that enables flexible adjustment of the period and height of corrugation. We demonstrate that fabrication of stable and electrically efficient OLEDs on these rough substrates is feasible. Sharp spectral features are superimposed onto the broad emission spectra of the OLEDs, providing clear evidence for Bragg scattering of light from guided modes into the air cone. Theoretical analysis based on an emissive dipole model and conservation of momentum considerations allows a quantitative description of scattering and the associated dispersion relations.