OLED electrodes made from graphene for the first time

The team, from the Fraunhofer Institute for organic electronics, electron beam and plasma technology FEP in Dresden was working on an EU-funded project known as Gladiator which focuses on production, characterisation and integration of graphene layers. OLEDs (organic light-emitting diodes) are becoming increasingly common in display screens, both large-scale for televisions and small-scale for telephones and other handheld devices; they have superior colour-generating properties compared to inorganic LEDs and are particularly useful in touchscreens.

Working with project partners Graphenea of Spain, a specialist in producing graphene by chemical vapour composition, and Aixtron, a German company which produces vapour deposition equipment for the electronics and semiconductor industry from its facility in Cambridge, the Fraunhofer team placed a wafer of high-purity copper into a stainless steel vacuum chamber and heated it to 800°C before exposing it to a mixture of methane and hydrogen. The methane dissolves in the copper and forms carbon atoms, which spread across the surface of the plate, organising themselves into a layer of graphene. This takes only a few minutes, according to the team.