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Title: Formation of blade and slot die coated small molecule multilayers for OLED applications studied theoretically and by XPS depth profiling

Abstract

Slot die coaters especially designed for low material consumption and doctor blades were used to process small molecule solutions for organic light-emitting diodes (OLEDs). Optimum process parameters were developed for the large-scale coating techniques to generate stable single and multiple layers only a few nanometers thick. Achieving a multilayer architecture for solution-processed OLEDs is the most challenging step. X-ray photoelectron spectroscopy sputter depth profiling was performed to determine defined interfaces between coated organic layers. Commercially available small molecules NPB (N,N’-Di(1-naphthyl)-N,N’-diphenyl-(1,1’-biphenyl)-4,4’-diamine) and BAlq (Bis(8-hdroxy-2methylquinoline)-(4-phenylphenoxy)aluminum), originally developed for vacuum deposition, were used as hole, respectively electron transport material. Defined double-layers were processed with both scalable coating methods using the orthogonal solvent approach. The use of non-orthogonal solvents resulted in complete intermixing of the material. The results are explained by calculations of solubilities and simulating drying and diffusion kinetics of the small molecule solutions.

Authors:
; ; ;  [1];  [2];  [3]
  1. Institute of Thermal Process Engineering, Thin Film Technology, Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany)
  2. Philips Technologie GmbH Innovative Technologies, Aachen (Germany)
  3. Institute for Applied Materials and Karlsruhe Nano Micro Facility (KNMF), Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany)
Publication Date:
OSTI Identifier:
22611532
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM; BIPHENYL; DIES; DIFFUSION; INTERFACES; LAYERS; LIGHT EMITTING DIODES; MOLECULES; ORGANIC SEMICONDUCTORS; SOLUBILITY; SPUTTERING; VACUUM COATING; VISIBLE RADIATION; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Peters, Katharina, Raupp, Sebastian, E-mail: sebastian.raupp@kit.edu, Scharfer, Philip, Schabel, Wilhelm, Hummel, Helga, and Bruns, Michael. Formation of blade and slot die coated small molecule multilayers for OLED applications studied theoretically and by XPS depth profiling. United States: N. p., 2016. Web. doi:10.1063/1.4953845.
Peters, Katharina, Raupp, Sebastian, E-mail: sebastian.raupp@kit.edu, Scharfer, Philip, Schabel, Wilhelm, Hummel, Helga, & Bruns, Michael. Formation of blade and slot die coated small molecule multilayers for OLED applications studied theoretically and by XPS depth profiling. United States. doi:10.1063/1.4953845.
Peters, Katharina, Raupp, Sebastian, E-mail: sebastian.raupp@kit.edu, Scharfer, Philip, Schabel, Wilhelm, Hummel, Helga, and Bruns, Michael. 2016. "Formation of blade and slot die coated small molecule multilayers for OLED applications studied theoretically and by XPS depth profiling". United States. doi:10.1063/1.4953845.
@article{osti_22611532,
title = {Formation of blade and slot die coated small molecule multilayers for OLED applications studied theoretically and by XPS depth profiling},
author = {Peters, Katharina and Raupp, Sebastian, E-mail: sebastian.raupp@kit.edu and Scharfer, Philip and Schabel, Wilhelm and Hummel, Helga and Bruns, Michael},
abstractNote = {Slot die coaters especially designed for low material consumption and doctor blades were used to process small molecule solutions for organic light-emitting diodes (OLEDs). Optimum process parameters were developed for the large-scale coating techniques to generate stable single and multiple layers only a few nanometers thick. Achieving a multilayer architecture for solution-processed OLEDs is the most challenging step. X-ray photoelectron spectroscopy sputter depth profiling was performed to determine defined interfaces between coated organic layers. Commercially available small molecules NPB (N,N’-Di(1-naphthyl)-N,N’-diphenyl-(1,1’-biphenyl)-4,4’-diamine) and BAlq (Bis(8-hdroxy-2methylquinoline)-(4-phenylphenoxy)aluminum), originally developed for vacuum deposition, were used as hole, respectively electron transport material. Defined double-layers were processed with both scalable coating methods using the orthogonal solvent approach. The use of non-orthogonal solvents resulted in complete intermixing of the material. The results are explained by calculations of solubilities and simulating drying and diffusion kinetics of the small molecule solutions.},
doi = {10.1063/1.4953845},
journal = {AIP Advances},
number = 6,
volume = 6,
place = {United States},
year = 2016,
month = 6
}
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