Abstract
Horizontal orientation of the emission transition dipole moments achieved in glassy vapor-deposited organic thin films leads to an enhancement of the light out-coupling efficiency in organic light-emitting diodes (OLEDs). Here, our combined study of variable angle spectroscopic ellipsometry and angle dependent photoluminescence demonstrates that such a horizontal orientation can be achieved in glassy spin-coated organic films based on a composite blend of a heptafluorene derivative as a dopant and a 4,4′-bis(N-carbazolyl)-1,1′-biphenyl as a host. Solution-processed fluorescent OLEDs with horizontally oriented heptafluorene emitters were then fabricated and emitted deep blue electroluminescence with an external quantum efficiency as high as 5.3%.
Original language | English |
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Article number | 063301 |
Journal | Applied Physics Letters |
Volume | 106 |
Issue number | 6 |
DOIs | |
Publication status | Published - Feb 9 2015 |
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)