An advanced coating technique has allowed a team at the University of Toronto to build the highest-efficiency OLED device ever reported with a glass-free design.
in the University of Toronto’s Department of Materials Science &
Engineering have developed the world’s most efficient organic
light-emitting diodes (OLEDs) on plastic. This result enables a flexible
form factor, not to mention a less costly, alternative to traditional
OLED manufacturing, which currently relies on rigid glass.
The results are reported online in the latest issue of Nature Photonics.
provide high-contrast and low-energy displays that are rapidly becoming
the dominant technology for advanced electronic screens. They are
already used in some cell phone and other smaller-scale applications.
state-of-the-art OLEDs are produced using heavy-metal doped glass in
order to achieve high efficiency and brightness, which makes them
expensive to manufacture, heavy, rigid and fragile.
years, the biggest excitement behind OLED technologies has been the
potential to effectively produce them on flexible plastic,” says
Materials Science & Engineering Professor Zheng-Hong Lu, the Canada
Research Chair (Tier I) in Organic Optoelectronics.
plastic can substantially reduce the cost of production, while
providing designers with a more durable and flexible material to use in
research, which was supervised by Professor Lu and led by PhD
Candidates Zhibin Wang and Michael G. Helander, demonstrated the first
high-efficiency OLED on plastic. The performance of their device is
comparable with the best glass-based OLEDs, while providing the benefits
offered by using plastic.
discovery, unlocks the full potential of OLEDs, leading the way to
energy-efficient, flexible and impact-resistant displays,” says
and Helander were able to re-construct the high-refractive index
property previously limited to heavy metal-doped glass by using a 50-100
nm thick layer of tantalum(V) oxide (Ta2O5), an advanced optical
thin-film coating material. This advanced coating technique, when
applied on flexible plastic, allowed the team to build the
highest-efficiency OLED device ever reported with a glass-free design.
Science & Engineering PhD Candidate Michael G. Helander discusses
the research that led to the development of the world’s most efficient
flexible OLED on plastic.