We demonstrate that dramatically improved hole injection can be achieved by inserting a very thin C60 film between the indium tin oxide (ITO) electrode and N,N′-diphenyl-N,N′-bis(1,1′-biphenyl)-4,4′-diamine (NPB) layer. This result is ascribed to the formation of an interfacial dipole layer of buckminsterfullerene (C60) on the ITO electrode. The dipole layer induces the surface potential shift that contributes to improve the charge injection efficiency. The chemical shift was downward to help lower the hole injection energy barrier from the ITO electrode to the NPB layer, consistent with the moderately strong electron accepting nature of C60. The enhanced-charge injection provides a simple way of reducing the power consumption of organic electronic devices for real applications.

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Flat and homogeneous films by ink jet printing of organic materials are proven to be essential for OLED application. The impact of ink formulation, film thickness, pixel size, bank layout and process conditions (i.e. drying parameters) have been investigated. Their severe impact on device performance is illustrated.

In this paper, we present novel OLED display technologies with distinctive image quality and design for premium TV using an advanced coplanar IGZO TFT backplane, meta‐lit lens array (MLA) based OLED which increase out‐coupling efficiency, N‐line shared gate driver in panel (GIP), and one scan compensation technology. Using these technologies, we improved the luminance efficiency about 20 %, reduced the size of the panel bezel by 34 %, and have successfully developed world's largest 8K OLED TVs.

Dramatically improved power efficiency and stability of organic light-emitting diodes (OLEDs) were achieved by using buckminsterfullerene (C 60 ) as an interlayer between indium tin oxide (ITO) anode and hole transporting layer of N, N 0 -diphenyl-N, N 0 -bis(1,1 0 -biphenyl)-4,4 0 -diamine (NPB) and electron transporting layer (ETL) at the same time. The results are ascribed to the interfacial-dipole formation of C 60 on the surface of ITO anode and Ohmic cathode contact of C 60 . The surface dipole of C 60 on the ITO anode helps to lower the hole injection energy barrier from ITO to NPB. C 60 also has an Ohmic cathode contact with high electron mobility in the typical structure of C 60 =LiF=Al. These properties of C 60 make it possible to simultaneously enhance the electron and hole injection from both cathode and anode. Lowered operating voltage by surface dipole and Ohmic cathode contact of C 60 can eliminate Joule heating at both organic=cathode and organic=anode interfaces and as a result, provides the improved stability of OLEDs.