Tri-layer soft UV imprint lithography and fabrication of high density pillars

We report on results of the fabrication of high density pillars over a large area by UV assisted soft nanoimprint lithography (UV-NIL). A tri-layer process has been used which allowed us to obtain an enhanced process latitude with a good compatibility to the commonly used pattern transfer techniques. As example, high density SiO"2 pillars of diameter 200nm and aspect ratio 8 has been obtained by reactive ion etching with a nickel mask. Experiences of surface functionalization have been performed with fluorescent protein molecules and a linear increase of the fluorescence intensity has been found as the effective surface per area increases. Preliminary results of enzymatic reaction on the patterned surface in microfluidic channels are also described. Finally, water condensation behavior on patterned surfaces has been observed, indicating the possibility of controlling the wetting properties with high density pillars.