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High-resolution features are key to achieve high performance printed electronics devices such as transistors. Gravure printing is very promising to achieve high resolution in combination with high printing speeds on the order of 1m/s. High-speed gravure has recently been shown to print high resolution features down to linewidths and spacing of 2μm. Whilst this was a tremendous improvement over previous reports, these results had been obtained using silicon printing plates. These silicon printing plates are fabricated using microfabrication techniques which offer several advantages over traditional metal gravure cylinders where the features are defined by techniques such as stylus engraving, laser engraving or etching. This offers much greater precision and design freedom in terms of feature size, surface roughness, cell placement and cell shape. However, rigid silicon printing plates cannot be used in a roll-to-roll printing process that would truly enable low-cost printed electronics. Here we demonstrate for the first time a gravure printing roll that combines the precision of silicon printing plates with the form factor of a metal cylinder. The fabrication process starts with a silicon master whose pattern is replicated by polymer molding. The actual metal printing plate is then built up on the polymer negative of the pattern by a combination of electroless and electroplating. After separation of the polymer and the metal, the metal printing plate can be mounted on a magnetic roll for printing. Printing of highly scaled 2μm features is demonstrated. Different metal surfaces were explored to optimize printing performance and wear during printing.
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