SCHOTT solutions no. 1/2015 > Organic Electronics
Flexibility will have an impact on many areas of life in the future. Besides using OLED modules in different types of displays, flat ”warm” light that doesn’t blind the eyes will soon no longer be a dream for foldable or rollable screens. Photo: tesa
Flexible Electronics on Rolled Glass
The industry consortium KONFEKT is developing new technologies for the use of glass-on-a-roll in organic electronics. The project that SCHOTT is involved in is being supported by the German Federal Government.
Dr. Haike Frank
The three technology companies SCHOTT, tesa and VON ARDENNE have joined to work as a consortium on an exciting project. KONFEKT is aimed at driving forward the development of ultra-thin glass-on-a-roll for use in applications, such as organic electronics, to produce future generations of OLED applications. The goal is to refine flexible glass through lamination with functional adhesive tapes and the application of specific functional layers. The hope is that this will result in a rolled-up substrate that can be easily processed, providing unique properties for many applications in roll form. Germany’s Federal Ministry of Education and Research (BMBF) is supporting this development for a period of three years with a total of 5.6 million euros.
The research consortium KONFEKT (thin glass for glass-polymer laminates) is focusing on two features of thin glass. In the first subproject, a laminate made of ultra-thin glass with an adhesive tape barrier, which will hermetically encapsulate electronic components, is being developed. In the second subproject, a solution will be developed that shows how ultra-thin glass can serve as a functional substrate for demanding applications such as the components of organic electronics.
SCHOTT manufactures ultra-thin glass that is only 25 to 150 microns thick and ideally suited for roll-to-roll applications. Photo: SCHOTT
In subproject one, SCHOTT and tesa are working together to protect sensitive electronic components such as OLEDs (organic light-emitting diodes) from humidity and oxygen by using ultra-thin glass. Reliable encapsulation protects the sensitive components against aging. Flexible glass is well-suited as a barrier material because it forms a layer that is chemically impermeable to water vapor and oxygen, even in a thickness of a few 10 micrometers. In addition, unlike coating solutions, flexible glass does not have any pinholes. tesa’s expertise as a developer of specialty tapes comes into play in lateral sealing. The ultra-thin glass will be delivered to the user rolled up and laminated with a special adhesive layer.
In the second subproject, the equipment manufacturer VON ARDENNE is developing a vacuum coating system specifically for roll-to-roll (R2R) coating of flexible glasses that will meet the special requirements of such glasses. Thin glass can thus be used as a functional substrate in sophisticated electronic applications. For example, a conductive TCO layer (transparent conductive oxide) such as ITO (indium tin oxide), which is needed to produce OLEDs or (organic) photovoltaic cells, will be applied using a special vacu-um-based PVD coating process (physical vapor deposition).
Photo left: The new transparent tesa barrier tapes equipped with the patented tesa DrySeal® Liner Technology can be processed safely and quickly by using roll-to-roll techniques. This process on full-surface OLED encapsulation saves time and money – and is an important building block for the production concept of the future. Photo: tesa. Photo right: Through finishing with a transparent electrode layer, flexible glass will be made available in the future as a substrate for the roll-to-roll production of flexible OLEDs. Photo: VON ARDENNE / Corporate Archive
”We expect the consortium to play an important role in the next three years in the development of a new production platform based on glass on a roll for innovative use in manufacturing electronic components,” says Dr. Ruediger Sprengard, Director of Business Development for Ultra-Thin Glass at SCHOTT. <