Slanted high‐aspect‐ratio polymer pillars are studied for their unique properties such as unidirectional spreading of liquid, directional adhesions, or alignment of cells, where the pillars are in constant contact with water or in a humid environment. These pillars, however, tend to cluster upon water evaporation due to the capillary force and lowered modulus of the pillars. Here, spontaneous recovery of clustered slanted hydrogel pillars to their original shape is presented by exploiting the modulus change of hydrogel materials during water evaporation. The clustering and recovery of the slanted hydrogel micropillars are monitored in situ by optical microscopy and environmental scanning electron microscopy. To elucidate sequential clustering and recovery mechanism, the adhesion force between the pillars and the restoring force is compared. Finally, the dynamic change of optical transparency is exploited as the result of switching between clustering and recovery of the slanted micropillars for display. The study of the deformation and recovery of slanted hydrogel pillars will offer insights into geometrical and material designs in water‐based applications.

Here, we propose a simple mechanoresponsive system on patterned soft surfaces to manipulate both anisotropy and orientation of liquid wetting. On the poly(dimethylsiloxane) embedding line patterned structures, additional topographies, such as wrinkles and cracks, can be provided by applying compressive and tensile stress, respectively. This tunable hierarchy of structures with the different scales and directions of lines, wrinkles, and cracks allow the mechanoresponsive control of anisotropic wetting in a single platform. In addition, the wetting behavior on those surfaces is precisely investigated based on the concept of critical contact angle to overcome the ridges in a step flow.

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EUV lithography has been one of the key factors that enables the continuation of semiconductor scaling beyond N7. While it is a vital technique for the HVM of the most recent advanced logic and DRAM devices, the EUVL still needs more efforts in order to fully exploit its capability and extend the application. One particular aspect that has been considered as of critical importance is the optical/chemical stochastic effects which may cause L/S, contact pattern defects limiting the efficiency of EUVL. The simplest way to alleviate the stochastic effects is to employ the higher EUV exposure dose; however, this approach is impractical as it obviously leads to even lower productivity. In this work, the alternative chemicals -such as EUV PTD developer and NTD rinse which are specifically prepared to overcome the stochastic effects -are examined to enhance the performance efficiency of EUVL. The focused features that thoroughly explored are EUV dose, local CD uniformity, PR swelling, pattern collapse, and defects. It is found that, with the chemical composition modification of developer and rinse, EUV pattern fidelity can be effectively optimized resulting in extended process window and improved productivity. It is expected that this work would not only facilitate the extension of EUV application but also help understand how EUV resists behave when they are under the influence of ancillaries.

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