Directional Photofluidization Lithography: Micro/Nanostructural Evolution by Photofluidic Motions of Azobenzene Materials

Abstract

This review demonstrates directional photofluidization lithography (DPL), which makes it possible to fabricate a generic and sophisticated micro/nanoarchitecture that would be difficult or impossible to attain with other methods. In particular, DPL differs from many of the existing micro/nanofabrication methods in that the post-treatment (i.e., photofluidization), after the preliminary fabrication process of the original micro/nanostructures, plays a pivotal role in the various micro/nanostructural evolutions including the deterministic reshaping of architectures, the reduction of structural roughness, and the dramatic enhancement of pattern resolution. Also, DPL techniques are directly compatible with a parallel and scalable micro/nanofabrication. Thus, DPL with such extraordinary advantages in micro/nanofabrication could provide compelling opportunities for basic micro/nanoscale science as well as for general technology applications.

Photoinduced Phase Transitions in Rod-shaped Azobenzene with Different Alkyl Chain Length

“…Photochromic reaction such as photoisomerization of azobenzene has been widely utilized in switching phases of liquid crystals [1][2][3], gels [2,4], and changing fluidity of polymer surfaces [5,6]. Characteristics of these photoresponsive materials is that state of matter can be controlled by photoirradiation without changing the temperature of the materials.…”

SRG Inscription in Supramolecular Liquid Crystalline Polymer Film: Replacement of Mesogens

“…The trans/cis photoisomerization cycle of Az under an interference laser illumination or patterned photo-illumination locally softens the Az polymers and induce lateral motions of the film materials. [1][2][3][4][5][6][7]. The resultant undulations correspond to the patterns of incident light modulations including both intensity [6,7] and polarization [1][2][3][4]8].…”

Supramolecular design principles for efficient photoresponsive polymer–azobenzene complexes

“…Additionally, in early 2018 light control of nano-objects especially focusing on using noncovalent interactions to couple azobenzene surfactants to these objects was reviewed, thus indicating the timeliness of employing supramolecular interactions in the design of photoresponsive materials. 63 For technological applications of light-responsive materials, which is out of the scope of the present review, we refer the readers to the reviews by Ichimura on the use of azobenzenes as LC alignment surfaces, 64 Lee et al on photofluidization lithography, 65 Seki et al on recent advancements in photoalignment, 66 Natansohn and Rochon on the application potential of both photo-orientation and photo-induced surface patterning, 67 and Priimagi and Schevchenko on the potential photonic applications of the photo-induced surface patterns. 68 2.…”