Work function modification of indium–tin–oxide used in organic light emitting devices

摘要: We report measurements on the modification of work function (WF) indium–tin–oxide (ITO) by deposition Au and Pt overlayers, chosen because their high WF inertness. ITO films glass substrates (resistance∼10 Ω/sq) were cleaned with an ultraviolet (UV)–ozone treatment before entry into ultrahigh vacuum system. Auger electron spectroscopy was used to determine surface composition. The change (±10 mV) determined a Kelvin probe technique correlated absolute coverage (in range 0 5×1015 Au cm−2. final values not very different from non-UV–ozone treated samples. Studies bulk covered in single deposition, showed that low value sequential experiments attributable adsorption hydrocarbons 1×10−10 Torr vacuum, useful increases are attainable electrodes gold layers which thin enough cause no obvious ITO’s transparency (⩽10%). A similar trend observed for layer but less sensitivity hydrocarbon adsorption.