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Multilayer OLEDs with four slot die-coated layers

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Abstract

For the first time, multilayer OLEDs with four solution-processed layers are fabricated step-by-step using slot die coating. A suitable choice of coating parameters and fluid formulation enables the application of different material classes as large-area homogeneous layers with thicknesses in the nanometer range. The AFM measurements of the slot die-coated layers consisting of small molecules showed Ra values of 0.21–0.28 nm, less than previously reported in the literature. Based on a two-layer reference OLED consisting of a HIL and EML, the stack architecture is first extended by a crosslinked HTL. These three-layer OLEDs with a crosslinked HTL achieve 70% higher efficiency, compared to that of the reference devices, thus assuming successfully separated layers. In a further step, an additional ETL is applied via the orthogonal solvent approach to obtain four solution-processed layers. The averaged power efficiency of the four-layer OLEDs is increased by a factor of 2.2 compared to the reference OLEDs up to a value of 3.5 lm/W. Based on these results, it can be assumed that both approaches, the use of orthogonal solvents as well as the application of crosslinkable materials, have been successfully combined to fabricate multilayer OLEDs with four separated slot die-coated layers.

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Abbreviations

AA:

Acetic acid

AFM:

Atomic force microscopy

Al:

Aluminum

CE:

Current efficiency

EML:

Emissive layer

ETL:

Electron transport layer

HIL:

Hole injection layer

HTL:

Hole transport layer

ITO:

Indium–tin-oxide

LiF:

Lithium fluoride

OPPI:

(4-Octyloxyphenyl) phenyliodonium hexafluoroantimonate

PEDOT:PSS:

Poly (3,4-ethylenedioxythiophene)-poly(styrenesulfonate)

PE:

Power efficiency

PVL:

Poly(N-vinylcarbazole)

QUPD:

N,N′-bis(4-(6-((3-ethyloxetan-3-yl)methoxy)-hexyloxy)phenyl)-N,N′-bis(4-methoxyphenyl)biphenyl-4,4′-diamine

TPBi:

2,2′,2″-(1,3,5-Benzinetriyl)-tris(1-phenyl-1-H-benzimidazole)

TSG-M:

Green emitter

References

  1. Meerholz, K, “Enlightening Solutions.” Science (New York, N.Y.), 309 (5741) 1728–1732 (2005)

    Article  Google Scholar 

  2. Raupp, SM, Merklein, L, Pathak, M, Scharfer, P, Schabel, W, “An Experimental Study on the Reproducibility of Different Multilayer OLED Materials Processed by Slot Die Coating.” Chem. Eng. Sci., 160 113–120 (2017)

    Article  CAS  Google Scholar 

  3. Peters, K, Raupp, S, Hummel, H, Bruns, M, Scharfer, P, Schabel, W, “Formation of Blade and Slot Die Coated Small Molecule Multilayers for OLED Applications Studied Theoretically and by XPS Depth Profiling.” AIP Adv., 6 (6) 65108 (2016)

    Article  Google Scholar 

  4. Gong, X, Wang, S, Moses, D, Bazan, GC, Heeger, AJ, “Multilayer Polymer Light-Emitting Diodes. White-Light Emission with High Efficiency.” Adv. Mater., 17 (17) 2053–2058 (2005)

    Article  CAS  Google Scholar 

  5. Xu, Y, Yang, R, Peng, J, Mikhailovsky, AA, Cao, Y, Nguyen, T-Q, Bazan, GC, “Solvent Effects on the Architecture and Performance of Polymer White-Light-Emitting Diodes with Conjugated Oligoelectrolyte Electron-Transport Layers.” Adv. Mater. (Deerfield Beach Fla.), 21 (5) 584–588 (2009)

    Article  CAS  Google Scholar 

  6. Ahrens, L, Schlisske, S, Strunk, K-P, Hinkel, F, Melzer, C, Bunz, UHF, Lemmer, U, Hernandez-Sosa, G, Jänsch, D, Freudenberg, J, Müllen, K, “Solubility Modulation of Polyfluorene Emitters by Thermally Induced (Retro)-Diels–Alder Cross-Linking of Cyclopentadienyl Substituents.” Chem. Mater., 30 (12) 4157–4167 (2018)

    Article  CAS  Google Scholar 

  7. Köhnen, A, Riegel, N, Müller, DC, Meerholz, K, “Surface-Initiated Phase Separation-Fabrication of Two-Layer Organic Light-Emitting Devices in a Single Processing Step.” Adv. Mater., 23 (37) 4301–4305 (2011)

    Article  Google Scholar 

  8. Rehmann, N, Hertel, D, Meerholz, K, Becker, H, Heun, S, “Highly Efficient Solution-Processed Phosphorescent Multilayer Organic Light-Emitting Diodes Based on Small-Molecule Hosts.” Appl. Phys. Lett., 91 (10) 103507 (2007)

    Article  Google Scholar 

  9. Ho, Szuheng, Liu, Shuyi, Chen, Ying, So, Franky, “Review of Recent Progress in Multilayer Solution-Processed Organic Light-Emitting Diodes.” J. Photon. Energy, 5 (1) 057611 (2015)

    Article  Google Scholar 

  10. Stolz, S, Petzoldt, M, Kotadiya, N, Rödlmeier, T, Eckstein, R, Freudenberg, J, Bunz, UHF, Lemmer, U, Mankel, E, Hamburger, M, Hernandez-Sosa, G, “One-Step Additive Crosslinking of Conjugated Polyelectrolyte Interlayers. Improved Lifetime and Performance of Solution-Processed OLEDs.” J. Mater. Chem. C, 4 (47) 11150–11156 (2016)

    Article  CAS  Google Scholar 

  11. Gorter, H, Coenen, MJJ, Slaats, MWL, Ren, M, Lu, W, Kuijpers, CJ, Groen, WA, “Toward Inkjet Printing of Small Molecule Organic Light Emitting Diodes.” Thin Solid Films, 532 11–15 (2013)

    Article  CAS  Google Scholar 

  12. Elschner, A, Heuer, HW, Jonas, F, Kirchmeyer, S, Wehrmann, R, Wussow, K, “Gallium Complexes in Three-Layer Organic Electroluminescent Devices.” Adv. Mater., 13 (23) 1811–1814 (2001)

    Article  CAS  Google Scholar 

  13. Raupp, SM, Merklein, L, Hietzschold, S, Zürn, M, Scharfer, P, Schabel, W, “Slot Die-Coated Blue SMOLED Multilayers.” J. Coat Technol. Res., 14 (5) 1029–1037 (2017)

    Article  CAS  Google Scholar 

  14. Höfle, S, Do, H, Mankel, E, Pfaff, M, Zhang, Z, Bahro, D, Mayer, T, Jaegermann, W, Gerthsen, D, Feldmann, C, Lemmer, U, Colsmann, A, “Molybdenum Oxide Anode Buffer Layers for Solution Processed, Blue Phosphorescent Small Molecule Organic Light Emitting Diodes.” Organic Electronics, 14 (7) 1820–1824 (2013)

    Article  Google Scholar 

  15. Zhao, Y, Duan, L, Zhang, D, Hou, L, Qiao, J, Wang, L, Qiu, Y, “Small Molecular Phosphorescent Organic Light-Emitting Diodes Using a Spin-Coated Hole Blocking Layer.” Appl. Phys. Lett., 100 (8) 83304 (2012)

    Article  Google Scholar 

  16. Yang, NC, Suh, MC, “Soluble Polymer Layers as an Anode Buffer for Organic Light-Emitting Diodes.” Curr. Appl. Phys., 9 (2) 505–509 (2009)

    Article  Google Scholar 

  17. Tseng, S-R, Meng, H-F, Yeh, C-H, Lai, H-C, Horng, S-F, Liao, H-H, Hsu, C-S, Lin, L-C, “High-Efficiency Blue Multilayer Polymer Light-Emitting Diode Fabricated by a General Liquid Buffer Method.” Synth. Met., 158 (3–4) 130–134 (2008)

    Article  CAS  Google Scholar 

  18. Tseng, S-R, Lin, S-C, Meng, H-F, Liao, H-H, Yeh, C-H, Lai, H-C, Horng, S-F, Hsu, C-S, “General Method to Solution-Process Multilayer Polymer Light-Emitting Diodes.” Appl. Phys. Lett., 88 (16) 163501 (2006)

    Article  Google Scholar 

  19. Suzuri, Y, Saito, A, Kita, H, Yamada, T, “Organic Electroluminescent Element and Its Manufacturing Method.” 6,960,364

  20. Höfle, S, Zhang, M, Dlugosch, J, Kuhn, M, Hamburger, M, Colsmann, A, “Thermo-Cleavable Poly(fluorene-benzothiadiazole) to Enable Solution Deposition of Multi-layer Organic Light Emitting Diodes.” Organ. Electron., 42 355–360 (2017)

    Article  Google Scholar 

  21. Hillebrandt, S, Adermann, T, Alt, M, Schinke, J, Glaser, T, Mankel, E, Hernandez-Sosa, G, Jaegermann, W, Lemmer, U, Pucci, A, Kowalsky, W, Müllen, K, Lovrincic, R, Hamburger, M, “Naphthalene Tetracarboxydiimide-Based n-Type Polymers with Removable Solubility via Thermally Cleavable Side Chains.” ACS Appl. Mater. Interfaces, 8 (7) 4940–4945 (2016)

    Article  CAS  Google Scholar 

  22. Duggal, AR, Heller, CM, Shiang, JJ, Liu, J, Lewis, LN, “Solution-Processed Organic Light-Emitting Diodes for Lighting.” J. Display Technol., 3 (2) 184–192 (2007)

    Article  CAS  Google Scholar 

  23. Krebs, FC, “Fabrication and Processing of Polymer Solar Cells. A Review of Printing and Coating Techniques.” Solar Energy Mater Solar Cells, 93 (4) 394–412 (2009)

    Article  CAS  Google Scholar 

  24. Chang, H-W, Lee, Y-T, Tseng, M-R, Jang, M-H, Yeh, H-C, Luo, F-T, Meng, H-F, Chen, C-T, Chi, Y, Qiu, Y, Duan, L, Lin, H-W, Horng, S-F, Zan, H-W, “General Application of Blade Coating to Small-Molecule Hosts for Organic Light-Emitting Diode.” Synth. Met., 196 99–109 (2014)

    Article  CAS  Google Scholar 

  25. Søndergaard, RR, Hösel, M, Krebs, FC, “Roll-to-Roll Fabrication of Large Area Functional Organic Materials.” J. Polym. Sci. B Polym. Phys., 51 (1) 16–34 (2013)

    Article  Google Scholar 

  26. Buerkin, CK, de Vries, I, Raupp, SM, Scharfer, P, Schabel, W, Groen, P, “Investigation of Interfacial Instabilities with a Two-Layer Slide Coating Process.” J Coat Technol Res, 14 (5) 991–1001 (2017)

    Article  CAS  Google Scholar 

  27. Horiuchi, R, Suszynski, WJ, Carvalho, MS, “Simultaneous Multilayer Coating of Water-Based and Alcohol-Based Solutions.” J Coat Technol Res, 12 (5) 819–826 (2015)

    Article  CAS  Google Scholar 

  28. Abbel, R, de Vries, I, Langen, A, Kirchner, G, t’Mannetje, H, Gorter, H, Wilson, J, Groen, P, “Toward High Volume Solution Based Roll-to-Roll Processing of OLEDs.” J. Mater. Res., 32 (12) 2219–2229 (2017)

    Article  CAS  Google Scholar 

  29. Schmitt, M, Diehm, R, Scharfer, P, Schabel, W, “An Experimental and Analytical Study on Intermittent Slot Die Coating of Viscoelastic Battery Slurries.” J. Coat. Technol. Res., 12 (5) 927–938 (2015)

    Article  CAS  Google Scholar 

  30. Raupp, SM, Schmitt, M, Walz, A-L, Diehm, R, Hummel, H, Scharfer, P, Schabel, W, “Slot Die Stripe Coating of Low Viscous Fluids.” J. Coat Technol. Res., 15 (5) 899–911 (2018)

    Article  CAS  Google Scholar 

  31. Schmitt, M, Raupp, S, Wagner, D, Scharfer, P, Schabel, W, “Analytical Determination of Process Windows for Bilayer Slot Die Coating.” J. Coat Technol. Res., 12 (5) 877–887 (2015)

    Article  CAS  Google Scholar 

  32. Raupp, S, Daume, D, Tekoglu, S, Merklein, L, Lemmer, U, Hernandez-Sosa, G, Sauer, HM, Dörsam, E, Scharfer, P, Schabel, W, “Slot Die Coated and Flexo Printed Highly Efficient SMOLEDs.” Adv. Mater. Technol., 2 (2) 1600230 (2017)

    Article  Google Scholar 

  33. Park, B, Kwon, OE, Yun, SH, Jeon, HG, Huh, YH, “Organic Semiconducting Layers Fabricated by Self-metered Slot-Die Coating For Solution-Processable Organic Light-Emitting Devices.” J. Mater. Chem. C, 2 (40) 8614–8621 (2014)

    Article  CAS  Google Scholar 

  34. Choi, K-J, Lee, J-Y, Park, J, Seo, Y-S, “Multilayer Slot-Die Coating of Large-Area Organic Light-Emitting Diodes.” Organ. Electron., 26 66–74 (2015)

    Article  CAS  Google Scholar 

  35. Choi, K-J, Lee, J-Y, Shin, D-K, Park, J, “Investigation on Slot-Die Coating of Hybrid Material Structure for OLED Lightings.” J. Phys. Chemi. Solids, 95 119–128 (2016)

    Article  CAS  Google Scholar 

  36. Gather, MC, Kronenberg, NM, Meerholz, K, “Monolithic Integration of Multi-color Organic LEDs by Grayscale Lithography.” Adv. Mater. (Deerfield Beach, Fla.), 22 (41) 4634–4638 (2010)

    Article  CAS  Google Scholar 

  37. Kim, SR, “Surface Modification of Poly(tetrafluoroethylene) Film by Chemical Etching, Plasma, and Ion Beam Treatments.” J. Appl. Polym. Sci., 77 1913–1920 (2000)

    Article  CAS  Google Scholar 

  38. Hegemann, D, Brunner, H, Oehr, C, “Plasma Treatment of Polymers for Surface and Adhesion Improvement.” Nucl. Instrum. Methods Phys. Res. Sect. B: Beam Interact. Mater. Atoms., 208 281–286 (2003)

    Article  CAS  Google Scholar 

  39. Instruments, V, Inc, “Manual: Dektak 150 Surface Profiler.” (2009)

  40. Bhansali, US, Polikarpov, E, Swensen, JS, Chen, W-H, Jia, H, Gaspar, DJ, Gnade, BE, Padmaperuma, AB, Omary, MA, “High-efficiency Turquoise-blue Electrophosphorescence from a Pt(II)-pyridyltriazolate Complex in a Phosphine Oxide Host.” Appl. Phys. Lett., 95 (23) 233304 (2009)

    Article  Google Scholar 

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Acknowledgments

The authors acknowledge financial support via the project POESIE (contract number 13N13692) of the Federal Ministry of Education and Research. We would like to thank all involved mechanics, assistants and our students for contributing to this work as well as TSE Troller AG, Murgenthal, Switzerland, for technical support. We thank Alexander Jurczok from IDD, Technische Universität Darmstadt for structuring the ITO substrates. The authors are also thankful for the support of the Innovation Lab GmbH, Heidelberg.

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Authors and Affiliations

  1. Institute of Thermal Process Engineering, Thin Film Technology, Karlsruhe Institute of Technology, Kaiserstrasse 12, 76131, Karlsruhe, Germany

    Lisa Merklein, Marvin Mink, Sebastian M. Raupp, Philip Scharfer & Wilhelm Schabel

  2. InnovationLab (iL), Speyerer Strasse 4, 69115, Heidelberg, Germany

    Lisa Merklein, Marvin Mink, Sebastian M. Raupp, Philip Scharfer & Wilhelm Schabel

  3. COPT Center for Organic Electronics, University of Cologne, Luxemburger Strasse 90, 50939, Cologne, Germany

    Dimitrios Kourkoulos & Klaus Meerholz

  4. Department of Chemistry, University of Cologne, Luxemburger Strasse 116, 50939, Cologne, Germany

    Dimitrios Kourkoulos, Benjamin Ulber & Klaus Meerholz

  5. ZOEK Zentrum für Organische Elektronik Köln gGmbH, Luxemburger Strasse 90, 50939, Cologne, Germany

    Klaus Meerholz

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  1. Lisa Merklein
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Correspondence to Lisa Merklein.

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Merklein, L., Mink, M., Kourkoulos, D. et al. Multilayer OLEDs with four slot die-coated layers. J Coat Technol Res 16, 1643–1652 (2019). https://doi.org/10.1007/s11998-019-00225-2

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