Graphene electrodes for OLED displays

Fraunhofer researchers together with partners from industry and research, have for the first time, produced functional OLED electrodes from graphene

3 Jan 2017 | Editor

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology (FEP) together with partners, has succeeded for the first time in producing OLED electrodes from graphene. The electrodes have an area of 2 × 1 cm².

The process was developed and optimised in the EU-funded project "Gladiator" (Graphene Layers: Production, Characterisation and Integration) together with partners from industry and research.

The production of the OLED electrodes takes place in a vacuum. In a steel chamber, a wafer plate of high-purity copper is heated to about 800 degrees. The research team then supplies a mixture of methane and hydrogen and initiates a chemical reaction. The methane dissolves in the copper and forms carbon atoms, which spread on the surface. This process only takes a few minutes. After a cooling phase, a carrier polymer is placed on the graphene and the copper plate is etched away.

Dr. Beatrice Beyer, FEP's project leader, said, "This was a real breakthrough in research and integration of extremely demanding materials." Beatrice added, "The first products could already be launched in two to three years."

Graphene is considered a new miracle material. The advantages of the carbon compound are impressive: graphene is light, transparent and extremely hard and has more tensile strength than steel. Moreover, it is flexible and extremely conductive for heat or electricity. Graphene consists of a single layer of carbon atoms which are assembled in a kind of honeycomb pattern. It is only 0.3 nanometers thick, which is about one hundred thousandth of a human hair.

Due to their flexibility, the graphene electrodes are ideal for touch screens. They do not break when the device drops to the ground. Instead of glass, one would use a transparent polymer film. Many other applications are also conceivable: in windows, the transparent graphene could regulate the light transmission or serve as an electrode in polarization filters. Graphene can also be used in photovoltaics, high-tech textiles and even in medicine.

Source: Fraunhofer FEP / Gladiator

About Gladiator EU Project

Gladiator project was launched in November 2013. The Fraunhofer team is working on the next steps until the conclusion in April 2017. During the remainder of the project, impurities and defects which occur during the transfer of the wafer-thin graphene to another carrier material are to be minimized.

The project is supported by the EU Commission with a total of 12.4 million euros. The Fraunhofer Institute’s important industrial partners are the Spanish company Graphenea S.A., which is responsible for the production of the graphene electrodes, as well as the British Aixtron Ltd., which is responsible for the construction of the production CVD reactors.

Source: Gladiator EU Project

About Fraunhofer FEP

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP works on innovative solutions in the fields of vacuum coating, surface treatment as well as organic semiconductors. The core competences electron beam technology, sputtering and plasma-activated deposition, high-rate PECVD as well as technologies for the organic electronics and IC/system design provide a basis for these activities.

Thus, Fraunhofer FEP offers a wide range of possibilities for research, development and pilot production, especially for the processing, sterilization, structuring and refining of surfaces as well as OLED microdisplays, organic and inorganic sensors, optical filters and flexible OLED lighting.

Our aim is to seize the innovation potential of the electron beam, plasma technology and organic electronics for new production processes and devices and to make it available for our customers. COMEDD (Center for Organics, Materials and Electronic Devices Dresden) with all known activities in organic electronics is now acting as a new business unit at Fraunhofer FEP, Dresden, Germany.

Source: Fraunhofer FEP