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The influence of CF4 plasma treatment of indium-tin-oxide (ITO) and polyimide (PI) on the patterning of ink-jet printed polymer is presented. Not much difference between the as-received ITO and PI surface energies was found, but a significant difference in surface energies between ITO and PI after CF4 plasma treatment was noted. It is expected that precise patterning can be achieved by using the difference in surface energies between the inside of the pixel and its surroundings. Also the effects of CF4 plasma treatment of ITO have been studied on the performance of polymer light-emitting diodes (PLEDs). X-ray photoelectron spectroscopy revealed that CF4 plasma treatment led to a decrease in the surface content of carbon contaminants and an increase in the surface content of fluorine, which in turn enhance the performance of PLEDs.

Organic light-emitting diodes (OLEDs) with aluminum cathodes prepared by the ion-beam-assisted deposition (IBAD) have a longer lifetime than thermally evaporated one. The electroluminescent features were examined to compare the rate of degradation in the devices with thermally evaporated Al cathodes and ion-beam-assisted Al cathodes. The dense and highly packed Al cathode effectively prevents the permeation of H 2 O and O 2 through pinhole defects, which results in retarding dark spot growth. Employing thin Al buffer layer diminished Ar + ion-induced damages in phenyl-substituted poly- p -phenylene-vinylene (Ph-PPVs) and limited permeation against H 2 O and O 2 . The interface between Al and Ph-PPV may be modified in IBAD case, even though buffered Al layer was deposited to 30 nm by thermal evaporation prior to Ar + ion beam irradiation. It is believed that the buffered Al film cannot screen the Ar + ions or Al atoms wholly due to the existence of pinholes or non-deposited regions among the columnar structures.

This article has been retracted at the request of the Editor-in-Chief and Author. Please see http://www.elsevier.com/locate/withdrawalpolicy . Reason: This article is part of an extreme case of duplicate publication in which the paper, or nearly identical copies of it, has appeared in at least nine other journals. The authors have acknowledged the abuse, which has also been brought to the attention of the responsible administrators at their institutions. Multiple publication represents a flagrant disregard of international copyright law and scientific ethics, it wastes reviewer's and journal staff time, and is also a very poor use of costly journal space which is explicitly reserved for publishing original work. Thin Solid Films takes a strong view on this matter.

We have fabricated highly stable organic electroluminescent devices based on spin-coated poly- p -phenylene-vynylene (PPV) thin films. The electrical properties of aluminum cathode, prepared by ion beam assisted deposition, on PPV have been investigated and compared to those by thermal evaporation. Although energetic particles of Al assisted by Ar + ion may damage the organic material, I – V – L characteristics are improved by applying thin Al buffer layer. In addition, a dense Al cathode inhibits the permeation of H 2 O and O 2 into PPV film through pinhole defects, and thus retards dark spot growth. It may be deduced from highly packed structure of Al cathode with smaller junction resistance between Al and PPV. In conclusion, the lifetime of organic light-emitting device (OLED) has been extended effectively by dense Al film through ion beam assisted deposition process.

Ion-beam-assisted deposition (IBAD) was used for cathode preparation in organic light-emitting diodes to fabricate dense electrode. Dark spot growth rate was decreased by employing the IBAD process due to a highly packed aluminum structure inhibiting the permeation of H2O and O2. However, undesirable leakage current was generated because energetic particles of Al assisted by Ar+ ion may damage the organic material resulting in reduction of contact resistance. The decrease of contact resistance in the IBAD device may be caused by large contact area, increase of density of states, and Li diffusion to phenyl-substituted poly-p-phenylene vinylene.

We have fabricated highly stable organic electroluminescent devices based on spin-coated poly-p-phenylene-vynylene (PPV) thin films. The electrical properties of aluminum cathode, prepared by ion beam assisted deposition, on PPV have been investigated and compared to those by thermal evaporation. Although energetic particles of Al assisted by Ar+ ion may damage the organic material, I–V–L characteristics are improved by applying thin Al buffer layer. In addition, a dense Al cathode inhibits the permeation of H2O and O2 into PPV film through pinhole defects, and thus retards dark spot growth. It may be deduced from highly packed structure of Al cathode with an increase in the contact area between Al and PPV that reduce the contact resistance. In conclusion, the lifetime of organic light-emitting device (OLED) has been extended effectively by dense Al film through ion beam assisted deposition process.

Highly stable organic electroluminescent devices based on spin-coated soluble phenyl-substituted poly- p -phenylene-vinylene (Ph-PPVs) thin films have been achieved. We investigated the electrical properties of ion beam assisted aluminum cathode contacting Ph-PPV and compared them to those of thermal evaporation. Although energetic particles of Al assisted by Ar + ion generate the damages in organic materials, I–V–L characteristics can be improved by using thin Al buffer layer to avoid damages. In addition, dense Al cathode inhibits the permeation of H 2 O and O 2 through pinhole defects, which results in retarding gas bubble formation. This may be explained by highly packed structure of Al cathode and decrease of the contact resistance between Al and Ph-PPV. It is believed that the larger contact area and increase of density of state in Ph-PPV minimize the contact resistance and that results in the longevity of organic light-emitting devices (OLEDs).

Microcavites contribute to enhancing the optical efficiency and color saturation of an organic light emitting diode (OLED) display. A major tradeoff of the strong cavity effect is its apparent color shift, especially for RGB-based OLED displays, due to their mismatched angular intensity distributions. To mitigate the color shift, in this work we first analyze the emission spectrum shifts and angular distributions for the OLEDs with strong and weak cavities, both theoretically and experimentally. Excellent agreement between simulation and measurement is obtained. Next, we propose a systematic approach for RGB-OLED displays based on multi-objective optimization algorithms. Three objectives, namely external quantum efficiency (EQE), color gamut coverage, and angular color shift of primary and mixed colors, can be optimized simultaneously. Our optimization algorithm is proven to be effective for suppressing color shift while keeping a relatively high optical efficiency and wide color gamut.

We have fabricated highly stable organic electroluminescent devices based on spin-coated soluble phenyl-substituted poly-p-phenylene-vinylene (Ph-PPVs) thin films. The electrical properties of aluminum cathode, prepared by ion-beam-assisted deposition, on Ph-PPV have been investigated and compared to those prepared by thermal evaporation. Although energetic particles of Al assisted by Ar+ ion may damage the organic material, I–V–L characteristics are improved by evaporating a thin Al buffer layer prior to ion-beam-assisted deposition. In addition, a dense Al cathode inhibits the permeation of H2O and O2 into Ph-PPV film by suppressing pinhole defects, and thus retards dark spot growth. This may be deduced from highly packed structure of Al cathode with smaller contact resistance between Al and Ph-PPV. The lifetime of an organic light-emitting device has been extended by dense Al film through an ion-beam-assisted deposition process.

Most of organic devices showed poor thermal stability and short lifetime due to Joule heating by current injection during operation. To increase the lifetime of the devices, thermal management must be considered. We demonstrated the polymer light-emitting diodes with thermally conductive substrate and Al/Cu double cathode to enhance the thermal stability of the device. Also, we proposed the correlation between lifetime (Δt) and device heat sink (ΔT). The heat sink of all organic devices is required to enhance device durability.

A semitransparent cathode of indium tin oxide (ITO)/Ag/ITO was developed as a resonant tunneling double barrier structure for transparent organic light-emitting diodes. A weak negative differential resistance was observed in devices using a 100nm thick ITO/Ag/ITO layer as a cathode in combination with a thin LiF∕Al layer. The current injection of devices was dominated by resonant tunneling, which induced no luminance at low voltage. This was achieved by employing an e-beam evaporated ITO/Ag/ITO cathode due to the double quantum barriers of ITO and the quantum well of Ag. The authors also applied the multilayer cathode to small molecule devices, which showed the same resonant tunneling currents.

The authors have investigated the effects of indium tin oxide (ITO) deposited by ion beam assisted e-beam evaporation on the performance of polymer light-emitting diodes. ITO was evaporated as a cathode onto a thin Mg:Ag layer by an e-beam process, and its performance as a transparent cathode was subsequently compared to that of Mg:Ag and sputtering-prepared ITO. Polymer devices’ luminance and efficiency were improved by more than ten times by ion beam assisted deposition (IBAD)-prepared ITO deposition, with little observable damage to the organic layer. Implementation of the IBAD process resulted in the reduction of the interfacial energy barrier which induced band bending. Furthermore, outcoupling with ITO resulted in enhanced luminance.

We report a fabrication of organic light-emitting diodes (OLEDs) based on soluble phenyl-substituted poly-p-phenylene-vinylene (Ph-PPVs) thin films with aluminum cathode prepared by ion-beam-assisted deposition (IBAD). The electrical properties of the aluminum cathode, prepared by IBAD, on Ph-PPV have been investigated and compared to those by thermal evaporation. Energetic particles of Al assisted by an Ar+ ion may damage the organic material generating undesirable leakage current even though a thin Al buffer layer is applied to avoid Ar+-ion-induced damages. Substantial improvements of passivation characteristics were observed in IBAD device because the dense Al cathode inhibits the permeation of H2O and O2 into Ph-PPV film through pinhole defects, and thus retards dark spot growth. These results may be deduced from the highly packed structure that has small contact resistance between Al and Ph-PPV in ion-beam-assisted aluminum devices.