Fuerth, Germany: A prime example for the innovation potential of printed electronics is the most recent development of PolyIC: high-resolution, conductive structures on transparent film that are produced in a roll-to-roll production process. These conductive structures can be used as an alternative to ITO (Indium Tin Oxide) films in display, touch sensor or electric heating element applications.
Foremost regarding the limited resources of for example indium sources the development of new technologies for the production of conductive layers is a goal that numerous research and development institutes pursuit. The new PolyIC technology is to produce transparent, conductive layers with structured and thin conductive paths made of metal with high conductivity and transparency. These conductive structures are applied on a thin and flexible film in a roll-to-roll process and can be used for example for displays, touch sensors or electric heating elements. Currently, for these applications, ITO films or thinly integrated metal wires are used.
The conductive structures by PolyIC have a resolution of 15 µm. They itself do not have to be transparent as the necessary translucence will be reached through the high-resolution structure i.e. that the conductive structures only occupy a fraction of the film (<10%). By the use of the high-resolution structure it is possible to apply light-tight, highly conductive materials such as metals. Through well-directed positioning of the process parameters it is possible to reach a conductivity of 0.4 – 1 Ohm/square for metal. The sheet resistance of the transparent film can be adjusted to e.g. typical values of ITO films.
Compared to ITO technology, the new PolyIC process offers various essential advantages: individual layouts due to customer requirements in high-resolution will replace cost-consuming structuring methods that are necessary when using ITO films, high transparency in a huge wavelength range and an individual, customer-specific sheet resistance can be realized. The PolyIC films can be produced in a roll-to-roll mass production process in high volume and are cost-effective in their applications. Especially the expense factor as well as limited resources asks for new technologies that can meet the demand of a steadily growing market primarily for displays and touch sensors. With this newly developed technology, PolyIC presents an attractive alternative for transparent conductive layers.