Silicone stamp

Fig. 10.25. Multilayer thin film capacitor structure printed in a single step on to a plastic substrate using the nanotransfer printing technique. A multilayer of Au/SiNx/Ti/ Au was first deposited on to a silicon stamp formed by photolithography and etching. Contacting this stamp to a substrate of Au/ PDMS/PET forms a cold weld that bonds the exposed Au on the stamp to the Au-coating on the substrate. Removing the stamp produces arrays of square (250 pm x 250 pm) metal/...

Subsequently, Loo and workers demonstrated cold welding at ambient pressures [21], Specifically, they fabricated a metal-insulator-metal capacitor (Au-SiN -Au) by cold welding. An Au/SiNx/Au multilayer stack was deposited on a silicon stamp and directly printed on an Au-coated PDMS/PET substrate. The details of this device were discussed previously in Section 5.5.4. 

In a previous experiment, we had utilized nanosphere lithography to create well-ordered nanostructures with tunable hydrophobicity on the surface [27]. However, such process is not compatible with micro-fabrication process. We have modified this technique by transferring the pattern of nanostructure into the silicon stamp and the nanostructures can be replicated by nanoimprint process. In other experiments, we had demonstrated that it was possible to create nanoimprint stamp with different... 

Figure 14 Principle of microcontact printing, in which a silicon or photoresist master is used to form a silicone stamp, which is in turn loaded with an ink such as an alkanethiol, which can then be used to transfer the original design as a chemical pattern onto a gold substrate, for example. Prom Reference 55 with kind permission.

The ability to assemble polymers in complex patterns on SAMs is illustrated in Figure 6.14 (40). The smallest feature size obtained via this process is about 5 pm. Cellulose acetate was used as a lithographic photomask to produce a silicon stamp for pCP of a patterned SAM... 

Silicone stamp Metal stamp forming process ... 

In the pure metal stamp forming process, both mold halves are made from metal. In silicone stamp forming, one mold half is mostly made from elastic material (mostly the upper mold half). Table 1.11 shows a comparison between both processes concerning the most important features. 

FIGURE 1.221 Forming mold with a lower mold half made from metal and a silicone stamp 1.8.3.3.3 Molds for the Diaphragm Technology... 

Figure 30. First, a NIL step was performed on the insulating polymer PMMA on a quartz substrate with a silicon stamp (Figure 30(a)). Then, an oxygen plasma treatment was used on the whole surface in order to remove PMMA in the embossed areas. The desired trenches with hydrophilic bottoms and surroimding bydropbobic walls with a defined hdght were obtained by an additional heating process, which converts the hydrophibc PMMA (induced by oxygen plasma treatment) into hydrophobic (Figure 30(b)).

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