In this paper we present a new roll-to-roll embossing process allowing the replication of micro patterns with feature sizes down to 0.5 mu m. The embossing process can be run in 'continuous mode' as well as in 'discontinuous mode'. Continuous hot embossing is suitable for the continuous output of micro patterned structures. Discontinuous hot embossing has the advantage that it is not accompanied by waste produced during the initial hot embossing phase. This is because in 'discontinuous mode', embossing does not start before the foil has reached the target temperature. The foil rests between two parallel heating plates and foil movement and embossing starts only after the part of the foil resting between the heating plates has reached a thermal steady state. A new type of embossing master is used which is based on flexible silicon substrates. The embossing pattern with sub-mu m topographic resolution is prepared on silicon wafers by state of the art lithography and dry etching techniques. The wafers are thinned down to a thickness of 40 mu m, which guarantees the mechanical flexibility of the embossing masters. Up to 20 individual chips with a size of 20 x 20 mmA(2) were assembled on a roller. Embossing experiments with COC foils showed a good replication of the silicon master structures in the foil. The maximum depth of the embossed holes was about 70% of the master height

Reel-to-reel processes like rotary hot embossing allow micro-patterning of flexible foil based polymer substrates. Such technologies have the potential to be the basis for extremely cheap micro-products. This is due to the low price for polymer foils as well as to the high throughput of reel-to-reel processes. An application field which could benefit of this technology is micro-fluidics. In this paper, a new type of reel-to-reel hot embossing machine will be presented. In contrast to commercially available reel-to-reel embossing machines, the machine described here is capable of doing continuous and discontinuous hot embossing. It is thus suited for fabrication of low, medium and high quantities of micro-patterned polymer components. It has been investigated how parameters like foil temperature, feed rate, embossing force, hardness of the counter roller and temperature of the embossing roller will influence the quality of the embossed structures. The results of this investigation will be presented and discussed

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