Units with complete electronic systems are increasingly replacing the production of individual components. Printed electronics are being applied, particularly in the areas of organic photovoltaics, gel electrolyte batteries, sensors, RFID antennae, displays, electro and thermochromic functional layers and OLEDs.
But how does this technology actually work?
The process can be compared to print technology. Instead of coloured inks, pastes or functional liquid, compounds are applied. Organic conductive materials, semiconductors, solar coatings or precious metals are printed. As is the case in multi-colour printing, precise layer structures and the correct order are extremely important.
This accuracy is achieved by precise web guiding in longitudinal and transverse directions, which also allows multiple printing or coating processes in a system – known as layer-by-layer processing. Drying technology also plays a role if accurate results are required. Convection dryers are the primary tool, but UV systems for the integration of barrier adhesives in laminating barrier layers, and thermal infrared in support of integration processes, are also applied.
The use of print technology allows the use of flexible base substrates that can be processed in a roll-to-roll process. It creates self-sufficient energy systems for use in medical, sports and protective clothing, electronics and photovoltaics. This opens a large range of possible applications, both from a dimensional and a final design point of view. As a consequence of the lower-costs of roll-to-roll processing, this process is also very interesting from an economical point of view.
The accuracy and sensitivity of the materials present the biggest challenges in production. Very thin coatings, in the range of 30nm, and very fine lines are not uncommon. Often an inert atmosphere is necessary to protect organic layers from oxygen and moisture, and must, as a rule, be under clean room conditions. The coatings are extremely sensitive to pressure and contact, and a scratch-free environment is a necessity. Protective measures for explosions should always be in place when working with solvents.
KROENERT-BMB-DRYTEC meets these challenges with a great deal of expertise and the most modern technology. The printing and coating technology of KROENERT-BMB-DRYTEC equipment is extremely accurate, and ultra-thin layering is possible. Optimised web guiding and control registers provide high gauge-pin accuracy for wet chemical layers printed over each other. Drying technology is adapted to the respective processes. Winding technology, such as a non-contact web guiding, is optimised and adapted to the substrates, making the handling of draw and pressure-sensitive films possible, for example through the use of non-contact web guiding.
Part Two in the series on ‘Printed Electronics’ will follow within the next months.
In the event of any questions please contact Frank Schäfer, frank.schaefer@kroenert.de, Tel. +49 40 853 93 169.