The trend towards higher packing densities and higher frequencies for telecommunication devices based on ceramic technology requires smaller dimensions for electrical wiring. In mass production, electrical thick film circuits for ceramic and LTCC-substrates have, up to now, been printed with screen printing. This technology is well known and widely used in commercial production. In conventional screen printing, the printing accuracy limit is about 150 μm in high volume production. By using advanced thick film technologies such as photo-imageable pastes, more accurate lines down to tens of μm can be produced. However, these processes are more complicated and costly compared with direct printing processes. In this paper, the Direct Gravure Printing (DGP) process using a metallic gravure plate has been developed to increase the line height of the fine printed lines. In DGP the paste is printed directly onto the substrate from a patterned gravure. The printing plate needed is made by electro-depositing over a relief patterned flat plate. The relief patterns can be made by resist technology. 100 % transfer of the printing paste from the gravure to the LTCC can be obtained by increasing the paste's internal cohesion by decreasing the printing temperature. The first results showed that, using the DGP process with metallic gravures, it is possible to print conductor lines down to 35 μm wide. The line height does not depend strongly on the line width, which is the main advantage of the DGP printing process.
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