Ultra-thin glass used for full roll-to-roll deposition of OLEDs
Ultra-thin glass (UTG) is an exciting material. It exhibits beneficial features known from rigid glass sheets like resistance against heat, UV-light and many chemicals as well as dimensional stability, high gas barrier performance and surface smoothness. Thanks to the thickness of only 200 µm or less, however, it also comes with benefits that are surprising for glass substrates, e.g. bendability and light weight – approx.
250 g/m² for 100 µm thick UTG.
Recently, various smartphone manufacturers have started to offer phones with foldable displays based on UTG. This high-priced application can recoup development costs of the UTG and finance the upscaling of production. In the medium term, this material should thus also become affordable for larger displays through to OLED light panels or even thin-film solar cells.
A consortium of industrial and research partners from Germany and Japan has demonstrated the potential of UTG for mass production by successfully setting up a pilot line for the manufacturing of organic light emitting diodes (OLEDs). This OLED pilot line is completely realized as a roll-to-roll process. The Japanese partners organized around the Yamagata University and the INOEL research institute contributed all steps from the manufacturing of 50 and 100 µm thick UTG over full area deposition of transparent conductive oxide (TCO) towards structuring of TCO by screen printed inks and further supportive process steps. Coils of UTG with structured TCO on top were shipped to Germany.
The German partners organized around the Organic Electronics Saxony cluster and Fraunhofer FEP research institute realized glass winding in an existing roll-to-roll OLED coater, transparent electrode evaporation, encapsulation, back-sheet lamination, separation of single modules as well as embedding the modules into demonstrators.
Within this public funded project called „LAOLA – Large Area OLED Lighting Applications“ (German Federal Ministry of Education and Research, funding code 03INT509AC), FHR contributed the reengi-neering of Fraunhofer’s metal strip OLED coater to handle UTG. Even so the preconditions set by the machine were by far not ideal for the new purpose, the coater can now reliably wind UTG with up to
1 m/min. Besides the detailed technical experience and data gained from this project, one of the major insights is both simple and crucial: Ultra-thin glass may still be brittle, but it is much more robust than expected and ready for being used in production.
FHR, Marian Böhling (CSO):„Ultra-thin glass is an amazing material. As the price falls, it will become the material of choice for more and more applications. FHR is prepared to offer customers the technology for coating ultra-thin glass with any type of thin films - whether for sensors, displays, batteries, OLEDs, thin-film photovoltaics or other applications.“
FHR Anlagenbau GmbH - The Thin Film Company was founded in 1991 and offers tailor-made vacuum coating systems and sputtering targets as well as coating and equipment service from a single source.
The close cooperation with our customers starts with the process development and continues with the development of pilot scale up to mass production. Our portfolio integrates the technologies sputtering, evaporation, PECVD and ALD into the equipment types cluster, inline, roll-to-roll and batch. Based in Germany and with systems installed worldwide in various industries such as semiconductors, MEMS, electronics, sensor technology, optics, photovoltaics, etc., we will jointly find vacuum coating solutions for our customers.
About FHR Anlagenbau GmbH
FHR Anlagenbau GmbH is specialised in the development of innovative thin-film coating technologies and vacuum coating equipment and renders various services in the field of thin-film technology. The major field of business is the construction of coating plants which feature a range of vapour deposition, magnetron sputtering, CVD and ALD technologies for industrial production and research applications. These systems are used in many branches of industry, including photovoltaics, in particular for CIGS solar cells and organic PV cells, solar thermal plants, optics, electronics, sensor technology, and in the automotive sector.
The product portfolio includes modular cluster systems for stationary coating of substrates, inline systems with vertical or horizontal substrate transport for coating glass plates or tube surfaces, as well as roll-to-roll plants for coating flexible substrates such as metal strips or polymer films. FHR closely collaborates with renowned research institutions and industry partners world-wide. The company takes a leading market position, in particular in the field of roll-to-roll vacuum coating equipment. In addition to plant engineering, FHR manufactures planar and tubular sputtering targets and has a powerful service department.