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The influence of plasma oxidation and other surface pretreatments on the electronic structure of indium–tin–oxide (ITO) thin films has been studied by high resolution x-ray photoemission spectroscopy. Plasma oxidation compensates n-type doping in the near surface region and leads to a reduction in the energy of plasmon satellite structure observed in In 3d core level spectra. In parallel, the Fermi level moves down within the conduction band, leading to a shift to low binding energy for both core and valence band photoemission features; and the work function increases by a value that corresponds roughly to the core and valence band binding energy shifts. These observations suggest that the conduction band of ITO is fixed relative to the vacuum level and that changes of work function are dominated by shifts of the Fermi level within the conduction band.

Thin films of In2O3 have been grown on Y-stabilized ZrO2(100) by oxygen plasma assisted molecular beam epitaxy with a substrate temperature of 650°C. Ordered epitaxial growth was confirmed by high resolution transmission electron microscopy. The position of the valence band onset in the x-ray photoemission spectra of the epitaxial films is found to be inconsistent with the widely quoted value of 3.75eV for the fundamental bandgap of In2O3 and suggests a revised value of 2.67eV.

A new, highly luminescent terbium complex (see Figure) is investigated here as a material for organic light‐emitting diodes (OLEDs). It is demonstrated that device efficiencies of over 2.6 lm/W are possible—the highest yet reported for a lanthanide‐based OLED. This indicates that lanthanide‐based materials are a viable alternative to Alq‐ and PPV‐based polymers for use in commercial OLED displays.

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