High-Performance Hybrid Buffer Layer Using 1,4,5,8,9,11-Hexaazatriphenylenehexacarbonitrile/Molybdenum Oxide in Inverted Top-Emitting Organic Light-Emitting Diodes

Abstract

A high-performance 1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile (HATCN)/molybdenum oxide (MoO3) hybrid buffer layer with high hole-injection efficiency and superior plasma resistance under the sputtering process was developed. The HATCN enhances the hole-injection efficiency, and the MoO3 effectively protects the underlying organic layers from plasma damage during deposition by sputtering. This improves the characteristics of inverted top-emitting organic light-emitting diodes using a top transparent conductive oxide electrode. The device using the hybrid buffer layer showed the highest electroluminescence characteristics among devices with other buffer layers. The high hole-injection efficiency of HATCN was shown by the J-F curve of hole-only devices, and the plasma protection performance of MoO3 was shown by atomic force microscope surface morphology images of the buffer layer film after O2 plasma treatment.

Efficient Organic Light Emitting Diodes Using Solution-Processed Alkali Metal Carbonate Doped ZnO as Electron Injection Layer

“…Compared with the conventional structure, the inverted OLEDs (IOLEDs), which use the air stable metals as top anode and indium-tin-oxide (ITO) as the cathode, have been considered as an advantageous approach to improve the stability and the roll-to-roll fabrication process of flat-panel display (Chu et al, 2006; Morii et al, 2006; Sessolo and Bolink, 2011; Chen et al, 2012; Guo et al, 2017; Fukagawa et al, 2018). Moreover, one benefit of the IOLED is to take advantage of the existing n-type amorphous silicon thin film transistor (a-Si TFT) technology for the development of the active-matrix driving OLED technology (Kabra et al, 2010; Hsieh et al, 2011; Zhong et al, 2011; Park et al, 2015; Hosono et al, 2017).…”

Open-shell doublet character in a hexaazatrinaphthylene trianion complex

“…[5][6][7] Metal-free HAT derivatives can display liquid crystal behaviour, 8 which, in tandem with their electron transport and semiconductor properties, 9 has introduced potential uses in organic electronics. [10][11][12][13][14][15] Electron-deficient HAT derivatives have also been used for anion recognition applications. 16 The ability of HAT-type ligands to bind up to three transition metal ions is of interest in the context of molecular magnetism.…”

Yb:MoO3/Ag/MoO3 Multilayer Transparent Top Cathode for Top-Emitting Green Quantum Dot Light-Emitting Diodes

“…As for conductive oxides, their deposition process requires the sputtering method or electron/ion beam-assisted techniques, causing plasma damage of the underlying films [22,23]. This sputtering damage may be alleviated to some degree by using an inserting layer, but complete protection is still a challenge [24][25][26]. Moreover, obtaining high quality oxide film with high transparency and conductivity often requires a high temperature that is harmful to the devices [23,27].…”