We report on a theoretical framework for the efficiency analysis of complex, multi-emitter organic light emitting diodes (OLEDs). The calculation approach makes use of electromagnetic modeling to quantify the overall OLED photon outcoupling efficiency and a phenomenological description for electrical and excitonic processes. From the comparison of optical modeling results and measurements of the total external quantum efficiency, we obtain reliable estimates of internal quantum yield. As application of the model, we analyze high-efficiency stacked white OLEDs and comment on the various efficiency loss channels present in the devices.
REFERENCES
1.
K. T.
Kamtekar
, A. P.
Monkman
, and M. R.
Bryce
, Adv. Mater.
22
, 572
(2010
).2.
S.
Reineke
, F.
Lindner
, G.
Schwartz
, N.
Seidler
, K.
Walzer
, B.
Lüssem
, and K.
Leo
, Nature
459
, 234
(2009
).3.
G.
He
, C.
Rothe
, S.
Murano
, A.
Werner
, O.
Zeika
, and J.
Birnstock
, J. Soc. Inf. Disp.
17
, 159
(2009
).4.
T. C.
Rosenow
, M.
Furno
, S.
Reineke
, S.
Olthof
, B.
Lüssem
, and K.
Leo
, J. Appl. Phys.
108
, 113113
(2010
).5.
P. Y.
Ngai
, Proc. SPIE
7617
, 761714
(2010
).6.
S.
Nowy
, B. C.
Krummacher
, J.
Frischeisen
, N. A.
Reinke
, and W.
Brütting
, J. Appl. Phys.
104
, 123109
(2008
).7.
M.
Flämmich
, M. C.
Gather
, N.
Danz
, D.
Michaelis
, and K.
Meerholz
, Appl. Phys. Lett.
95
, 263306
(2009
).8.
R.
Meerheim
, M.
Furno
, S.
Hofmann
, B.
Lüssem
, and K.
Leo
, Appl. Phys. Lett.
97
, 253305
(2010
).9.
S.
Mladenovski
, S.
Hofmann
, S.
Reineke
, L.
Penninck
, T.
Verschueren
, and K.
Neyts
, J. Appl. Phys.
109
, 083114
(2011
).10.
M.
Furno
, R.
Meerheim
, S.
Hofmann
, B.
Lüssem
, and K.
Leo
, Phys. Rev. B
85
, 115205
(2012
).11.
P.
Freitag
, S.
Reineke
, S.
Olthof
, M.
Furno
, B.
Lüssem
, and K.
Leo
, Org. Electron.
11
, 1676
(2010
).12.
C.
Weichsel
, S.
Reineke
, M.
Furno
, B.
Lüssem
, and K.
Leo
, J. Appl. Phys.
111
, 033102
(2012
).13.
M.
Schober
, S.
Olthof
, M.
Furno
, B.
Lüssem
, and K.
Leo
, Appl. Phys. Lett.
97
, 013303
(2010
).14.
M.
Schober
, M.
Anderson
, M.
Thomschke
, J.
Widmer
, M.
Furno
, R.
Scholz
, B.
Lüssem
, and K.
Leo
, Phys. Rev. B
84
, 165326
(2011
).15.
Self-consistency of the model requires .
16.
W. L.
Barnes
, J. Mod. Opt.
45
, 661
(1998
).17.
G. W.
Ford
and W. H.
Weber
, Phys. Rep.
113
, 195
(1984
).18.
K. A.
Neyts
, J. Opt. Soc. Am. A
15
, 962
(1998
).20.
M.
Carvelli
, R. A. J.
Janssen
, and R.
Coehoorn
, Phys. Rev. B
83
, 075203
(2011
).21.
See supplementary material at http://dx.doi.org/10.1063/1.4757610 for the detailed presentation of calculations results for device D1.
22.
G.
Schwartz
, S.
Reineke
, K.
Walzer
, and K.
Leo
, Appl. Phys. Lett.
92
, 053311
(2008
).23.
S.
Mladenovski
, K.
Neyts
, D.
Pavicic
, A.
Werner
, and C.
Rothe
, Opt. Express
17
, 7562
(2009
).24.
C. C.
Katsidis
and D. I.
Siapkas
, Appl. Opt.
41
, 3978
(2002
).25.
M.
Furno
, R.
Meerheim
, M.
Thomschke
, S.
Hofmann
, B.
Lüssem
, and K.
Leo
, Proc. SPIE
7617
, 761716
(2010
).26.
The efficiency loss is calculated according to the formula .
© 2012 American Institute of Physics.
2012
American Institute of Physics
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