Wettability patterning

This device comprises a hydrophobic surface using the wettability pattern of hydrophilic stripes for a surface-guided flow, micro channels [102], As substrates, hydrophobic materials were employed. The hydrophilic stripes were generated by mask-through thermal vapor deposition of MgF2 on a silicone mbber or thiolated gold substrate. 

M 18] [P 17] The wettable pattern can be used as micro-fluidic chips or micro reactors. Pairs or multiples of different hydrophobic stripes can be filled, e.g., with... 

In summary, a dewetting process is capable to transform a featureless and smooth film into a three-dimensional topography when a thin coating of finite thickness is deposited onto a chemical two-dimensional wettability pattern. Of course, the characteristic length-scale of the pattern and its periodicity are reproduced in the topographical structure. 

Mugele F, Klingner A, Buehrle J, Steinhauser D, Herminghaus S (2005) Electrowetting a convenient way to switchable wettability patterns. J Phys Condens Matter 17(9) S559-S576 Krupenkin T, Taylor JA, Kolodner P, Hodes M (2005) Electrically tunable superhydrophobic nanostructured surfaces. Bell Labs Tech J 10(3) 161-170... 

K. Nakata, H. Kimura, M. Sakai, T. Ochiai, H. Sakai, T. Murakami, M. Abe, and A. Fujishima, UV/thermally driven rewritable wettability patterns on Ti02-PDMS composite films, Appl. Mater. Interfaces, 2, 2485-2488 [2010]. 

With the two layer resist process, no effect of the surface structure is observed in the resulting resist pattern. A 0.35 wide lines with an aspect ratio of 6 have almost vertical side-walls and show a linewidth loss less than 0.1 iim by the etching of 2.0 thick AZ layer. In spite of the thin film of SNR, pin-holes were hardly observed in the dry-etched AZ patterns, presumably due to good wettability of silicone resin on organic film surface. 

A second limiting issue is the substrate oriented nature of this process. Since the pattern replication is essentially driven by a difference in wettability of the two components on the modified substrate, the aspect ratio (height/width) of the polymer structures is smaller than 1. It is unlikely that high aspect ratio polymer patterns can be made this way. 

Figure 13.11 The patterning of nanoparticle crystals by combination of photolithography and surface wettability.75 A concentrated nanoparticle solution slowly evaporated in the gaps between the patterned substrate and a glass substrate. When the structure was peeled off, patterned nanoparticle crystals on both surfaces were formed.

Keywords Core-shell particles Modification Patterned surfaces Roughness Wettability... 

On one hand it is investigated how the addition of cationic surfactants affects the pattern collapse of 193 nm photoresist lines. On the other hand, the adsorption of the surfactant on model photoresist surfaces is explored by a variety of surface chemical methods. Of special interest is how the surfactant changes the surface properties of the photoresist as surface potential and wettability. For an optimum modelling of the properties of real photoresist structures, both unexposed photoresists and photoresists that have been UV exposed, baked and developed are studied. 

Of special importance for the capillary forces responsible for the pattern collapse is the wettability of the photore-... 

Owing to the properties of the formulations used and the characteristics of the ponds tested, the patterns of accumulation and decline of residues in the two experiments were considerably different, as illustrated in Figure 1. The concentration of dichlobenil in water in the Tishomingo ponds treated with wettable powder was highest in the sample taken 3 days following treatment. A level of 50 p.p.m. was measured, which was two and one-half times treatment level. We cannot explain this anomalous level error in treatment does not appear likely, nor does stratification or localization of the dichlobenil within the pond, especially since the water sample was a composite of portions taken at four different points. The only possibility that seems worth considering is that some of the powder from the formulation could have been floating at the surface where it could easily have become part of the sample. 

Figure 2 shows a pattern of residues in fish similar to that for water. Fish in the Tishomingo ponds treated with 20 p.p.m. of the wettable powder quickly absorbed high amounts of the herbicide whole-body... 

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