Air-stable organic polymer red light-emitting devices on flexible plastic substrates

Hong, Yongtaek; He, Zhiqi; Lee, Shu-jen; Kanicki, Jerzy

doi:10.1117/12.457492

Cited by 6 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All the measured values were expressed as the root-mean-square values characterized by the following equation: (6) where X i , X ave , and N are the measured values, average of the measured values, and total number of measurements for a specific area, respectively. Fig.…”

Section: Tce Electrical and Optical Characteristicsmentioning

confidence: 99%

Transparent flexible plastic substrates for organic light-emitting devices

Hong

Lennhoff³

et al. 2004

Journal of Elec Materi

Self Cite

View full text Add to dashboard Cite

In this paper, we describe the properties of flexible plastic substrates with a transparent conducting electrode (TCE), which are important for organic lightemitting devices (OLEDs). Specifically, we have evaluated the TCE electrical resistivity, surface roughness, electrode patterning, optical transmission, and the substrate water vapor/oxygen transmission. We have studied the effect of ultraviolet (UV)-ozone treatment on the TCE surface by using contact angle measurements and x-ray photoelectron spectroscopy (XPS). A decrease in the advancing contact angle by 30-40°and an increase of oxygen content on the TCE surface by 10 at.% were observed after the UV-ozone treatment. These changes facilitate the polymer adhesion to the TCE surface and increase the TCE surface work function, respectively. A sheet resistance of 12-13 Ω/I I, an optical transmission greater than 80% over the visible range, and a surface roughness of 1.4-2.2-nm RMS over 50 ϫ 50 µm 2 have been obtained for the plastic substrates. These properties are adequate for OLED applications based on United States Display Consortium specifications. Finally, we have found that a combination of hydrogenated amorphous silicon-nitride and siliconoxide layers deposited on one side of the substrate at low-temperature reduces the water vapor and oxygen transmission rates (TRs) to less than 10 Ϫ5 g/cm 2 -day-atm and about 10 Ϫ7 cc/cm 2 -day-atm, respectively.

show abstract

Section: Tce Electrical and Optical Characteristicsmentioning

confidence: 99%

Transparent flexible plastic substrates for organic light-emitting devices

Hong

Lennhoff³

et al. 2004

Journal of Elec Materi

Self Cite

View full text Add to dashboard Cite

show abstract

“…4 and 5. If we assume that the PLED carrier injection at different interfaces is due to field-emission tunneling [30], the electron and hole injection currents can be expressed by at (2) at (3) where and are the effective mass of holes and electrons, respectively, q is the electron charge, is the reduced Plank constant, and E is the electric field. If we assume that the LEL behaves as a p-type semi-conductor [31] and the carrier transport in the LEL is a drift-type in a high electric field [32], we can describe the evolution of hole and electron density with the time by the following continuity equation [33]: with (4) with (5) where the and are the electron and hole mobilities, respectively, G and R are the generation and recombination rate of carriers in the LEL, respectively, and d is the thickness of LEL.…”

Section: A Opto-electronic Characteristicsmentioning

confidence: 99%

White LED based on polyfluorene Co-polymers blend on plastic substrate

Lee

Johnson

Kanicki

2006

IEEE Trans. Electron Devices

View full text Add to dashboard Cite

We report on high-performance, white light emission from polyfluorene co-polymers blend and study of the opto-electrical properties of polymer blend light-emitting devices (PLEDs) fabricated on plastic substrate. Our results show that efficient white light emission via energy transfer, producing higher device efficiencies and luminance in comparison with the conventional single PLEDs, can be realized by blending carrier donor (host) and acceptor (guest) organic polyfluorene co-polymers. A maximum luminance of 7400 cd/m 2 was achieved at 13 V with Internationale de L'Eclairage coordinates of (0.33, 0.33). Maximum emission efficiency of 2 0 cd/A and power efficiency of 1 1 lm/W are obtained for white light PLEDs on plastic substrate. Index Terms-Flexible plastic substrate, polymer blend, polymer light-emitting diodes (PLEDs), white polymer light-emitting diodes (WPLEDs). I. INTRODUCTION O VER the last several years, light-emitting devices (LEDs) based on organic materials have been attractive research subjects because of their potential applicability to large-size flat panel displays (FPDs) and solid-state lighting. The use of plastic substrates can add both device flexibility and reduced thickness, weight, and manufacturing costs of large-area FPDs [1]-[4]. Also, white light single-layer organic LEDs (OLEDs) can be used as a plane light source for current large-area liquid-crystal display (LCD) TVs and as back plane for future flexible full color displays in combination with color filters. Since the early 1990s, there have been many studies reporting the white light emission from either small moleculeor polymer-based devices. In 1995, Kido et al. developed an OLED consisting of three emitter layers with different carrier transport properties, each emitting blue, green, and red light to generate the white light [5]. In 1999, Deshpande et al. also demonstrated a white light emitting OLED consisting of green and blue emitting layers doped with a red emitting material. Here, the light emission was controlled by varying the concentration of the doping material and the thickness of Manuscript

show abstract

“…2(b), we observed oxidation and reduction peaks for the polymer thin films. Because it is believed that the edge of the oxidation potential (E ox ) represents the triggering point of the oxidation process, 17 we used this value to define the HOMO level of our emissive polymer. The edge of the reduction potential (E red ) was used to calculate the LUMO level of the polymer.…”

Section: Electrochemical Propertiesmentioning

confidence: 99%

“…It is usually assumed that the Ferrocene/Ferrocenium (Fc/Fc + ) oxidation potential (E 1/2 ) corresponds to 4.8 eV in reference to the vacuum. 17 Hence, this factor was used to estimate the I p and E a of the polymeric materials, thus defining the HOMO and LUMO levels, respectively. Different values for the light-emissive polymers are listed in Table 1.…”

Section: Electrochemical Propertiesmentioning

confidence: 99%

“…One of the possible candidates is the plastic substrate extensively used by our group over last several years. [16][17][18] In this paper, we describe the organic polymer light-emitting devices (PLEDs) fabricated over the poly(dicylo-pentadiene) substrate, such as the material produced by LOFO High Tech Film GmbH under the trade name "Transphan." 19,20 2…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Optoelectronic properties of poly(fluorene) co‐polymer light‐emitting devices on a plastic substrate*

et al. 2005

Self Cite

View full text Add to dashboard Cite

Abstract— The optoelectronic properties of red, green, and blue poly(fluorene) co‐polymer light‐emitting devices (PLEDs) on a plastic substrate having a multi‐layered structure with water vapor and oxygen transmission rates of less than 10−5 g/cm2‐day‐atm and 10−7 cc/cm2‐day‐atm, respectively, is reported. A semitransparent thin metal multi‐layer (i.e., Au/Ag/Au or Ag/Au/Ag) is placed between the plastic substrate and the ITO coating, achieving a low sheet resistance of 12–13 Ω/□ and an adequate optical transmission greater than 75%. A wider color gamut and a maximum emission efficiency of 0.7, 10, and 1.7 cd/A for red, green, and blue PLEDs, respectively, was obtained. Finally, a simple equivalent‐circuit model was used to simulate the current‐density—voltage characteristics of PLEDs.

show abstract

Air-stable organic polymer red light-emitting devices on flexible plastic substrates

Cited by 6 publications

References 0 publications

Transparent flexible plastic substrates for organic light-emitting devices

Transparent flexible plastic substrates for organic light-emitting devices

White LED based on polyfluorene Co-polymers blend on plastic substrate

Optoelectronic properties of poly(fluorene) co‐polymer light‐emitting devices on a plastic substrate*

Contact Info

Product

Resources

About