Pattern formation in thin polymeric films via electrohydrodynamic patterning

• Published in: RSC advances Vol. 12; no. 16; pp. 9681 - 9697
• Main Authors: Lv, Guowei, Tian, Hongmiao, Shao, Jinyou, Yu, Demei
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 25.03.2022; The Royal Society of Chemistry
• Subjects: Chemistry; Electric fields; Electrohydrodynamics; Film thickness; Free surfaces; High aspect ratio; Patterning; Polymer films; Rheological properties; Substrates; Surface tension; Thin films
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/d2ra01109c

The free surface of a thin polymeric film is often unstable and deforms into various micro-/nano-patterns under an externally applied electric field. This paper reviews a recent patterning technique, electrohydrodynamic patterning (EHDP), a straightforward, cost-effective and contactless bottom-up method. The theoretical and numerical studies of EHDP are shown. How the characteristic wavelength and the characteristic time depend on both the external conditions (such as voltage, film thickness, template-substrate spacing) and the initial polymer properties (such as rheological property, electrical property and surface tension) is theoretically and experimentally discussed. Various possible strategies for fabricating high-aspect-ratio or hierarchical patterns are theoretically and experimentally reviewed. Aligning and ordering of the anisotropic polymers by EHDP is emphasized. A perspective, including novelty and limitations of the methods, particularly in comparison to some conventional patterning techniques, and a possible future direction of research, is presented.