Control of work function of indium tin oxide: A surface treatment by atmospheric-pressure plasma layer on fabric-type electrodes

Abstract

The surface electronic properties of metal oxides, which affect the performances of layered electronic devices, are controlled by non-thermal atmospheric-pressure plasmas generated using a fabric-type electrode and gas flow induced through this plasma layer. We specify a method to control the work function of indium tin oxide (ITO) films by this plasma, in which such reactive species as oxidant radicals are generated. These oxidants are spatially transported in the gas flow to the ITO surface and increase the ITO’s work function, as verified in our experimental results. To examine the effects of the increased work function in a specific electronic device, we treat the surface of an ITO electrode in an organic light-emitting diode and observe the enhancement of the light-emitting efficiency.

The oxidation and surface speciation of indium and indium oxides exposed to atmospheric oxidants

“…4 The work function of ITO can be altered by the method and parameters of preparation and a major contributor to this variation in properties is likely humidity. 5,6 SnO 2 nanoparticles have even been used as humidity sensors, showing significant conductivity perturbation in the presence of varying water vapor pressure. 7 Little attention has been placed on the role of In 2 O 3 -water interactions and essentially no studies have been done to discern the impact of atmospheric water on the speciation at the indium solid-gas interface.…”

Effects of hydrogen-damaged layer on tin-doped indium oxide etching by H2/Ar plasma

“…Given that typical thin-film electroluminescent devices such as amorphous silicon solar cells and electroluminescent displays have a micropattern of materials, more effective micro=nanoscale processing is required. 1,2) A fabrication technology of ITO has been conventionally carried out by wet etching using a mixture of hydrochloric and nitric acids. The wet etching, however, is used for ITO and IZO patterned films with a large area (>2 µm).…”