Explaining the different efficiency behaviors of pholeds with/without a hole injection barrier at the hole transport layer/emitter layer interface

Organic Electronics

Volumn 14, Issue 10, 2013, Pages 2510-2517

  Siboni, Hossein Zamani ^a   Aziz, Hany ^a  

^a UNIVERSITY OF WATERLOO   (Canada)

Author keywords

Efficiency roll off; Emission mechanism; Triplet polaron quenching; Triplet triplet annihilation

Indexed keywords

CHARGE INJECTION; EFFICIENCY; ELECTRON INJECTION; EXCITONS; IRIDIUM COMPOUNDS; POLARONS; QUENCHING; SOUND INSULATING MATERIALS;

ELECTRONS AND HOLES; EMISSION MECHANISM; HOLE INJECTION BARRIERS; HOLE TRANSPORT LAYERS; INJECTION BARRIERS; RECOMBINATION ZONES; ROLL OFFS; TRIPLET-TRIPLET ANNIHILATION;

HOLE CONCENTRATION;

EID: 84885408546     PISSN: 15661199     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.orgel.2013.06.021     Document Type: Article

References (26)

1. C. Adachi, M.A. Baldo, M.E. Thompson, S.R. Forrest, Nearly 100% internal phosphorescence efficiency in an organic light-emitting device, J. Appl. Phys. 90 (2001) 5048-5051. (Pubitemid 33597058)
2. K. Goushi, R. Kwong, J.J. Brown, H. Sasabe, C. Adachi, Triplet exciton confinement and unconfinement by adjacent hole-transport layers, J. Appl. Phys. 95 (2004) 7798-7802.
3. J. Lee, J. Lee, K. Song, S.J. Lee, H.Y. Chu, Influence of doping profile on the efficiency of blue phosphorescent organic light-emitting diodes, Appl. Phys. Lett. 92 (2008). 133304-1333043.
4. M. Lee, J. Lin, M. Chu, M. Tseng, Suppression of efficiency roll off in blue phosphorescent organic light-emitting devices using double emission layers with additional carrier-transporting material, Appl. Phys. Lett. 94 (2009). 083506-0835063.
5. M.A. Baldo, C. Adachi, S.R. Forrest, Transient analysis of organic electrophosphorescence II Transient analysis of triplet-triplet annihilation, Phys. Rev. B 62 (2000) 10967-10977. (Pubitemid 32367268)
6. S. Reineke, K. Walzer, K. Leo, Triplet-exciton quenching in organic phosphorescent light-emitting diodes with Ir-based emitters, Phys. Rev. B 75 (2007) 125328.
7. S.H. Kim, J. Jang, K.S. Yook, J.Y. Lee, Stable efficiency roll-off in phosphorescent organic light-emitting diodes, Appl. Phys. Lett. 92 (2008). 023513-0235133.
8. B. Diouf, W.S. Jeon, R. Pode, J.H. Kwon, Efficiency control in iridium complex-based phosphorescent light-emitting diodes, Adv. Mater. Sci. Eng. 2012 (2012).
9. G. Schwartz, S. Reineke, K. Walzer, K. Leo, Reduced efficiency roll-off in high-efficiency hybrid white organic light-emitting diodes, Appl. Phys. Lett. 92 (2008) 053311.
10. S. Tokito, T. Iijima, Y. Suzuri, H. Kita, T. Tsuzuki, F. Sato, Confinement of triplet energy on phosphorescent molecules for highly-efficient organic blue-light-emitting devices, Appl. Phys. Lett. 83 (2003) 569- 571.
11. J.H. Kwon, W.S. Jeon, T.J. Park, 23.4: Invited Paper: Ideal Host-Dopant System for Highly Efficient Phosphorescent OLEDs, SID Symp. Dig. Tec. 40 (2009) 317-320.
12. M.A. Baldo, S. Lamansky, P.E. Burrows, M.E. Thompson, S.R. Forrest, Very high-efficiency green organic light-emitting devices based on electrophosphorescence, Appl. Phys. Lett. 75 (1999) 4-6. (Pubitemid 129308859)
13. D. Song, S. Zhao, Y. Luo, H. Aziz, Causes of efficiency roll-off in phosphorescent organic light emitting devices: Triplet-triplet annihilation versus triplet-polaron quenching, Appl. Phys. Lett. 97 (2010) 243304.
14. S.O. Jeon, K.S. Yook, C.W. Joo, J.Y. Lee, Theoretical maximum quantum efficiency in red phosphorescent organic light-emitting diodes at a low doping concentration using a spirobenzofluorene type triplet host material, Org. Electron. 11 (2010) 881-886.
15. Y. Chang, D.P. Puzzo, Z. Wang, M.G. Helander, J. Qiu, J. Castrucci, Z. Lu, Improving the efficiency of red phosphorescent organic light emitting diodes by exciton management, Phys. Status Solidi C 9 (2012) 2537-2540.
16. Z.B. Wang, M.G. Helander, J. Qiu, D.P. Puzzo, M.T. Greiner, Z.W. Liu, Z.H. Lu, Highly simplified phosphorescent organic light emitting diode with >20% external quantum efficiency at >10, 000 cd/m2, Appl. Phys. Lett. 98 (2011) 073310-073313.
17. Z.D. Popovic, H. Aziz, Delayed electroluminescence: A new tool for studies of OLED fundamental properties, Proc. SPIE - Int. Soc. Opt. Eng. 5937 (2005) 59370-59371.
18. Y. Luo, H. Aziz, Probing triplet-triplet annihilation zone and determining triplet exciton diffusion length by using delayed electroluminescence, J. Appl. Phys. 107 (2010) 094510.
19. Y. Kawamura, K. Goushi, J. Brooks, J.J. Brown, H. Sasabe, C. Adachi, 100% phosphorescence quantum efficiency of Ir (III) complexes in organic semiconductor films, Appl. Phys. Lett. 86 (2005) 071104.
20. H. Lee, S.W. Cho, K. Han, P.E. Jeon, C. Whang, K. Jeong, K. Cho, Y. Yi, The origin of the hole injection improvements at indium tin oxide/molybdenum trioxide/N, N0-bis(1-naphthyl)-N, N0-diphenyl-1, 10- biphenyl-4, 40-diamine interfaces, Appl. Phys. Lett. 93 (2008). 043308-3.
21. A.J. Makinen, I.G. Hill, Z.H. Kafafi, Vacuum level alignment in organic guest-host systems, J. Appl. Phys. 92 (2002) 1598-1603.
22. H. Kanno, Y. Sun, S.R. Forrest, White organic light-emitting device based on a compound fluorescent-phosphor-sensitized-fluorescent emission layer, Appl. Phys. Lett. 89 (2006). 143516-1435163.
23. H. Zamani Siboni, H. Aziz, Triplet-polaron quenching by charges on guest molecules in phosphorescent organic light emitting devices, Appl. Phys. Lett. 101 (2012). 063502-0635024.
24. M. Baldo, D. O'brien, Y. You, A. Shoustikov, S. Sibley, M. Thompson, S. Forrest, Highly efficient phosphorescent emission from organic electroluminescent devices, Nature 395 (1998) 151-154. (Pubitemid 28425649)
25. V.I. Adamovich, S.R. Cordero, P.I. Djurovich, A. Tamayo, M.E. Thompson, B.W. D'Andrade, S.R. Forrest, New charge-carrier blocking materials for high efficiency OLEDs, Org. Electron. 4 (2003) 77-87.
26. S.H. Kim, J. Jang, K.S. Yook, J.Y. Lee, M. Gong, S. Ryu, G. Chang, H.J. Chang, Triplet host engineering for triplet exciton management in phosphorescent organic light-emitting diodes, J. Appl. Phys. 103 (2008). 054502-0545024.