Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > Manufacturing/Packaging

P3T makes flexible ICs sustainable

Posted: 26 Oct 2010 ?? ?Print Version ?Bookmark and Share

Keywords:flexible circuits? reel-to-reel technology? plasma printing?

Researchers from the Fraunhofer Institute for Surface Engineering and Thin Films (IST) have developed a process for making thin film circuits and biosensors by applying conductive metal circuits to plastic substrates. They say that the process is more sustainable than traditional processes because it reduces material and energy used.

Flexible circuits are used in electronics where space and weight considerations are very important, including cars, cameras and video equipment, mini-computers for athletes, and inkjet printers. And the market is growing, with Frost & Sullivan forecasting sales of more than $16 billion by 2014.

The reel-to-reel technology is called plasma printing and packaging technology (P3T). Unlike previous methods, the researchers do not start with a polymer film metallized over its entire surface from which excess metal is then removed to create the circuits. Instead, to produce flexible circuit boards, they apply circuits made of copper to the film that serves as substrate. In the case of biosensors, palladium is used. They use plasma at atmospheric pressure and galvanization instead of vacuum-pressure and laser-based methods to achieve inexpensive and resource-efficient production.

Michael Thomas, director of the research group at IST, explains "During production of circuits for an RFID antenna, you often have to etch away between 50 and 80 percent of the copper used. This results in considerable amounts of copper scrap that either has to be disposed or reprocessed using relatively elaborate methods." P3T, on the other hand, uses the additive process to apply the structures directly to the substrate sheeting.

The first two process steps in P3T are plasma printing at atmospheric pressure and metallization using galvanization methods. Plasma printing uses the kind of deeply engraved roller familiar from the area of conventional rotogravure printing. During the printing process, microplasms are electrically generated in the engraved recesses of the roller; these microplasms chemically alter the surface of the plastic substrate where the circuits are to be applied later in the process.

The process gas from which the plasma is created is usually a mixture of nitrogenous gases. Thomas says that "The chemical changes we need begin to form on the surface of the film; these changes ensure that the plastic can be wetted with water in these precise areas and will be metallizable using suitable plating baths. This means considerable savings of energy and material."

Very important savings considering that the prices of raw materials including copper and palladium have risen by around 150 percent in the past three years.

IST is demonstrating the process at the K 2010 trade fair for plastics in D�sseldorf, Germany. The P3T project is sponsored by the German Federal Ministry of Education and Research.

Find related content:
??-?company/industry news
??-?new products

Article Comments - P3T makes flexible ICs sustainable
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top