Electronic devices have advanced from their heavy, bulky origins to become smart, mobile appliances. Nevertheless, they remain rigid, which precludes their intimate integration into everyday life. Flexible, textile and stretchable electronics are emerging research areas and may yield mainstream technologies. Rollable and unbreakable backplanes with amorphous silicon field-effect transistors on steel substrates only 3 μm thick have been demonstrated. On polymer substrates, bending radii of 0.1 mm have been achieved in flexible electronic devices. Concurrently, the need for compliant electronics that can not only be flexed but also conform to three-dimensional shapes has emerged. Approaches include the transfer of ultrathin polyimide layers encapsulating silicon CMOS circuits onto pre-stretched elastomers, the use of conductive elastomers integrated with organic field-effect transistors (OFETs) on polyimide islands, and fabrication of OFETs and gold interconnects on elastic substrates to realize pressure, temperature and optical sensors. Here we present a platform that makes electronics both virtually unbreakable and imperceptible. Fabricated directly on ultrathin (1 μm) polymer foils, our electronic circuits are light (3 g m(-2)) and ultraflexible and conform to their ambient, dynamic environment. Organic transistors with an ultra-dense oxide gate dielectric a few nanometres thick formed at room temperature enable sophisticated large-area electronic foils with unprecedented mechanical and environmental stability: they withstand repeated bending to radii of 5 μm and less, can be crumpled like paper, accommodate stretching up to 230% on prestrained elastomers, and can be operated at high temperatures and in aqueous environments. Because manufacturing costs of organic electronics are potentially low, imperceptible electronic foils may be as common in the future as plastic wrap is today. Applications include matrix-addressed tactile sensor foils for health care and monitoring, thin-film heaters, temperature and infrared sensors, displays, and organic solar cells.

An ultra-lightweight design for imperceptible plastic electronics

The present invention provides a heterocyclic compound and an organic light-emitting device including the heterocyclic compound. The organic light-emitting devices using the heterocyclic compounds have high-efficiency, low driving voltage, high luminance and long lifespan.

Organic light-emitting device

Polymers for flexible displays: From material selection to device applications

The Discovery and Development of Conducting Polymers The Scope of This Historical Overview Introduction An Early Example: Polyaniline The First Electrically Conductive Poly(Heterocycle): Polypyrrole The Fundamental Breakthrough: Doped Polyacetylene Conductive Polymers versus Metals and Insulators Metals, Semiconductors, and Insulators Conjugated Polymers Temperature-Dependent Conductivity Order and Disorder Polythiophenes: A Chance for Maximum Conductivity? Oxygen-Substituted Polythiophenes A Short History of the PEDOT Invention The Synthesis of EDOT Monomer, and Its Physical and Chemical Properties Monomer Synthesis Physical Properties Chemical Properties From EDOT to PEDOT: Oxidative Polymerization and Other Routes Oxidative Polymerization and Doping "Self-Oxidation" of EDOT Halogen Derivatives The Organometallic Route to PEDOT Neutral, Undoped PEDOT by Oxidative Polymerization Counterions for PEDOT Counterions in Electrochemically Polymerized PEDOT Counterions in Chemically Polymerized PEDOT The In Situ Polymerization of EDOT to PEDOT Synthesis of In Situ PEDOT Properties of In Situ PEDOT In Situ Polymerization of EDOT Derivatives and Relatives PEDOT: PSS PEDOT: PSS Dispersions Properties of PEDOT: PSS Secondary Doping Applications Solid Electrolyte Capacitors Through Hole Plating for Printed Wiring Boards ITO Substitution Antistatic Coatings Electroluminescent Lamps Organic Light Emitting Diodes (OLEDs) PEDOT:PSS in Organic Solar Cells Electrochromic Behavior Organic Field-Effect Transistors Technical Use and Commercial Aspects EDOT and PEDOT Derivatives with Covalently Attached Side Groups EDOT-CH2OH and Its Derivatives EDOT-CH2Cl and Its Follow-Up Products Alkyl EDOTs Water Soluble, "Self-Doping" EDOT Derivatives XDOTs, EDXTs, EDOXs, and 2(5)-X(2)-EDOTs: Ring Size Variations, Heteroanalogs, and Derivatives of EDOT with Substituents at the Thiophene Ring 3,4-Methylenedioxythiophene (MDOT) ProDOT (Propylenedioxythiophene) Derivatives Vinylenedioxythiophene (VDOT) and Benzo-EDOT 3,4-Ethyleneoxythiathiophene (EOTT) 3,4-Ethylene dithiathiophene (EDTT) 3,4-Ethylenedioxypyrrole (EDOP) and Its Derivatives 3,4-Ethylenedioxyselenophene (EDOS) 2,5-Disubstituted EDOT Derivatives [2(,5)-X(2)-EDOTs] The Electrochemical Behavior of EDOT and PEDOT

PEDOT : Principles and Applications of an Intrinsically Conductive Polymer

An organic light emitting display apparatus that has high (or improved) contrast and/or impact resistance. The organic light emitting display apparatus includes: a substrate; an organic light emitting device on the substrate to display an image; a sealing member on the organic light emitting device; a semitransparent film on a surface of the sealing member facing away from the organic light emitting device to transmit a portion of external light and to reflect another portion of the external light; a passivation film on the semitransparent film to protect the semitransparent film; and a transmissive black layer between the sealing member and the organic light emitting device to increase contrast, wherein the semitransparent film has a refractive index greater than that of the passivation film.

Organic light emitting display apparatus

Highly sensitive permeation measurements are crucial for the characterization and development of polymeric substrates for flexible display applications. In particular, organic light-emitting devices require substrates with extremely low permeation rates for water and oxygen. Here we demonstrate a concept for measuring ultralow permeation rates. The amount of oxidative degradation in a thin Ca sensor is monitored by in situ resistance measurements. The benefits of this technique are demonstrated for polyester foils with single- and double-sided barrier coatings. A sensitivity limit is imposed by the quality of the encapsulation. The resulting base line contribution to the water vapor transmission rate of a glass reference is below 10−6 g/m2 day at accelerated test conditions.

Permeation rate measurements by electrical analysis of calcium corrosion

Light extraction from OLEDs for lighting applications through light scattering

Organic light-emitting diodes were fabricated on a 125-μm-thick polyethylene terephthalate substrate covered with 100 nm indium tin oxide. The luminance–current–voltage performance and the emission spectrum of the devices are investigated in the bent state under mechanical stress at different bending radii. Down to a curvature of 15 mm, no significant decrease in the device performance is found compared to the relaxed state, as well as to conventional devices on glass substrates.

Performance of flexible polymeric light-emitting diodes under bending conditions

Joule heating and its impact on the brightness homogeneity are investigated since the luminance distribution is a key issue in large area organic light emitting diodes. In addition to previous reports, it is also important to consider the device temperature as a main factor for determining the luminance homogeneity. At a luminance of 1000cd∕m2 the active area reaches an average temperature of 40.6°C and a peak of 46.2°C. The increased device temperature is leading to higher local current densities resulting in a reduced brightness homogeneity. Modeling confirms these results and can be used for further device layout optimization.

Impact of Joule heating on the brightness homogeneity of organic light emitting devices

The invention relates to a method for producing an electronic component that comprises barrier layers for encapsulating the component, comprising the following steps: making available a substrate (1) having at least one functional layer (22), applying at least one first barrier layer (3) to the functional layer (22) by way of plasma-less atomic layer deposition (PLALD) and applying at least one second barrier layer (4) to the functional layer (22) by way of plasma-enhanced chemical vapor deposition (PECVD).

Ralph Paetzold

Papers

Permeation rate measurements by electrical analysis of calcium corrosion

Light extraction from OLEDs for lighting applications through light scattering

Performance of flexible polymeric light-emitting diodes under bending conditions

Impact of Joule heating on the brightness homogeneity of organic light emitting devices

Method for Producing an Electronic Component and Electronic Component