| CPC B63B 1/36 (2013.01) [B41F 13/22 (2013.01); B81B 1/006 (2013.01); F16C 19/00 (2013.01); B81B 2201/058 (2013.01); B81B 2203/0323 (2013.01); F16C 2240/54 (2013.01)] | 21 Claims |

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1. A substrate, comprising:
a surface formed by a non-wetting material; and
a wettable structure formed at the surface, wherein the wettable structure comprises a plurality of grooves, wherein the grooves are between 1 μm and 1 nm deep and have separations between 1 nm and 2 μm.
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