“Clean on Demand” Film could boost yields for roll-to-roll flexible electronics

As part of the EU-funded, Holst Centre-coordinated Clean4Yield project, DuPont Teijin Films (DTF) is developing a new ‘Clean-on-Demand’ PET polyester film that could boost yields and cut costs for roll-to-roll (R2R) production of flexible electronics. The new film features a protective layer that keeps the active surface of the film clean and free from particulate contamination until it is used, reducing defects.

High yields are essential for commercially viable mass-market flexible electronics. This latest development from DTF directly addresses one of the key issues affecting flexible electronics yields: defects caused by particulate contamination on the substrate. The new Clean-on-Demand film is covered with a protective layer that is removed immediately before depositing the barrier layer that protects the sensitive flexible electronics circuitry from the environment (the first step in producing a flexible electronic device).

Moreover, initial trials suggest that depositing and then removing the protective layer can change surface topography. Together, the lower contamination and altered surface smoothness allow high-quality barriers to be created using less material, significantly reducing manufacturing costs. In tests performed at Holst Centre, the Clean-on-Demand film with a single-layer silicon nitride barrier has already achieved water vapor transmission rates of just 5 x 10-5 g / m2 / day – around an order of magnitude better than today’s commercially available films.

“Although further work is required to commercialize the Clean-on-Demand film, these results show its potential to greatly reduce a major source of contamination in R2R production. Being part of the Clean4Yield project was crucial in our ability to develop the film. The project had the foresight to identify yields and particle contamination as the key challenges, and gave us the opportunity to explore solutions. It also brought us together with partners like Holst Centre, whose testing and insight helped accelerate development,” said Valentijn von Morgen, Senior Process Engineer at DuPont Teijin Films.

“DTF’s Clean-on-Demand film had some of the best water vapor transmission results we’ve ever seen with a silicon nitride barrier. Developing the film is part of Clean4Yield’s multi-pronged approach to addressing yield in R2R production of flexible electronics through the detection, cleaning, prevention and repair of defects and contamination. By bringing together partners from across the value chain, Clean4Yield provides an ideal setting for research and product development in this emerging market,” says Clean4Yield Project Manager Juliane Gabel of Holst Centre.

The Clean4Yield project was launched in May 2012 to develop technologies for inspecting, cleaning and repairing moving foils, and so ensure cost-effective production of printed electronics. Funded through the European Union’s Seventh Framework Programme (FP7) under Grant Agreement No. 281027, Clean4Yield brings together commercial and research partners from Europe and Israel and covers the entire value chain. For more information and the latest developments, please go to www.clean4yield.eu.

About DTF
DuPont Teijin Films is a leading global producer of PET and PEN polyester films, specialising in film products and related services for the Healthcare, Alternative Energy, Durable Media, Electronics, Specialist Packaging, Electrical Insulation and Capacitors Industries and many more. The company has approx 2,500 employees in dedicated marketing, technical and manufacturing operations in every region of the world.

Brand names include Mylar®, Melinex®, and Teijin® Tetoron® PET polyester film, and Teonex® PEN polyester film. The business includes existing joint ventures with DuPont-Hongji Films Foshan Co., Ltd., in China.

For more than 50 years DuPont Teijin Films has been putting leading-edge science to work to provide innovative filmic solutions for designers, engineers, specifies and end-users. We are a major supplier in the industry with an unmatched technology platform to continue bringing the most innovative solutions to serve customer needs, uniquely positioned to meet the requirements of markets ranging from packaging to industrial, electronics and specialities.

Because DuPont Teijin Films seeks to grow and evolve in a way that justifies the trust of its shareholders, customers and the public at large, the highest priority is placed on safety and the preservation of our natural environment.

DuPont Teijin Films is a 50:50 joint venture between DuPont and Teijin Limited. DuPont is a science company. Founded in 1802, DuPont puts science to work by solving problems and creating solutions that make people’s lives better, safer and easier. Operating in more than 70 countries, the company offers a wide range of products and services to markets including agriculture, nutrition, electronics, communications, safety and protection, home and construction, transportation and apparel. Teijin Limited is a major multinational enterprise offering fibres, chemicals and plastics, pharmaceuticals and medical products and diversified products. Teijin is using its proprietary technologies to expand into areas such as health-care products and services, advanced materials and information media.