Conductive pastes are the backbone of all printed electronics (PE) and play an important role in the further development of this technology. Due to their high performance and the lack of alternatives, silver-based pastes have dominated this market to date. The high price and incompatibility of silver pastes with standard processes for electronics assembly (especially soldering) are a challenge for the entry into new applications and for a higher acceptance of PE.
Previous and current attempts to use copper-based pastes have included changes in production technology such as photonic sintering systems or customized drying systems with reactive gases to overcome copper's ability to oxidize quickly. So far, such solutions have not been widely adopted by the industry.
Last year, PrintCB, a start-up from Israel, completed the development of a new generation of copper pastes. These can be applied by screen printing or using a microdispenser. Curing is possible with (standard) compressed air dryers at low temperatures (5 min at 150 °C), so that they are also suitable for PET films, papers and similar substrates. The use of these new copper pastes does not require any changes to the production machines. The conductivity of the conductor structures realized with them is comparable to that of silver pastes (<25 mΩ/square/mil) at lower costs. New functions such as the soldering of components directly with the paste and the suitability for operation at high temperatures open up new possibilities for the development of new applications, e.g. in hybrid electronics. DICO Electronic GmbH is the sales partner for this new paste in the D/A/CH region. The corresponding contract was concluded in November 2019. Information about the technical data etc. as well as test samples are available there. The material is available from stock.
PrintCB's research and development team is aware of the diverse requirements of the PE industry and the need for different specifications per application and is already working on the development of next-generation products. The vision and timeline for new copper pastes will be presented at LOPEC 2020 in Munich. As well as the properties of new copper pastes that are still under development, such as low temperature processing, flexibility, multilayer structure, component assembly and others. During the fair, new applications such as IoT and wireless devices, LED arrays, hybrid electronics, etc. will be presented, all of which have been realized using the new copper pastes.
www.dico-electronic.de
