Tungsten Oxide Buffer Layers Fabricated in an Inert Sol-Gel Process at Room-Temperature for Blue Organic Light-Emitting Diodes

• Published in: Advanced materials (Weinheim) Vol. 25; no. 30; pp. 4113 - 4116
• Main Authors: Höfle, Stefan, Bruns, Michael, Strässle, Stefan, Feldmann, Claus, Lemmer, Uli, Colsmann, Alexander
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 14.08.2013; WILEY‐VCH Verlag
• Subjects: Color; Current efficiency; Deposition; Equipment Design; Equipment Failure Analysis; Inert; Lighting - instrumentation; Materials Testing; Membranes, Artificial; OLED; Organic Chemicals - chemistry; Organic light emitting diodes; Oxides - chemistry; Phase Transition; precursor; Precursors; Semiconductors; Sol-gel processes; solution processing; Stoichiometry; Temperature; Tungsten - chemistry; tungsten oxide; Tungsten oxides; Voltage; precursor; tungsten oxide; OLED; solution processing
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.201301627

WO3 deposition from tungsten ethoxide precursor solutions at room temperature is demonstrated. The W(OEt)6 precursor can be converted under inert conditions and hence avoids sample contamination with oxygen, opening a pathway to more stable devices. The stoichiometry of all WO3 layers and the optoelectronic performance of the respective SMOLEDs well match thermally evaporated WO3 and its corresponding SMOLEDs. The solution processed WO3 hole injection layers enable the fabrication of blue phosphorescent OLEDs with low onset voltage and current efficiencies of up to 14 cd A−1.