Low-cost replication of self-organized sub-micron structures into polymer films

Abstract

Abstract. In this paper, the results of exploiting self-organized sub-micron polystyrene (PS) wrinkle patterns possessing random orientation, in preparation of a nickel stamp for hot embossing purposes, are presented. Self-organized patterns were prepared employing a method in which a stiff cross-linked capping layer on the topmost part of the soft polystyrene layer was created by using reactive ion etching (RIE) device with mild conditions and argon as a process gas, and the wrinkle formation was initiated thermally. Different surface patternings were obtained using silicon and stainless steel (SST) wafers as substrates. Prepared Ni-stamps were employed in hot embossing of polycarbonate (PC) and cyclo-olefin polymer (COP) films, using a nano-imprinting process. The replication quality of the self-organized wrinkle structures in PC and COP films was monitored by comparing the shape and dimensions of the original and final surface structures. The hot embossed sub-micron scale features, originally formed on stainless steel substrate, were found to have influence on the optical properties of the PC and COP films by lowering their reflectances.

Emergent Soft Lithographic Tools for the Fabrication of Functional Polymeric Microstructures

“…[73] Wrinkled surfaces, in addition to being PMs themselves, can be used to fabricate PMs of other materials by aligning polymer microparticles in the troughs of the wrinkles, [74][75][76] by using the relief microstructure of the wrinkles as stamps for μCP, [77][78][79] or by reproducing the wrinkles with replica molding and embossing procedures. [80,81] Wrinkled microstructures can be applied to the fabrication of PMs for many technological applications, including: triboelectric nanogenerators, [82][83][84] wettability patterns, [80,85] optically active surfaces, [81,86] smart adhesives with contact splitting properties, [87] and anti-fouling surfaces. [88] Surfaces with hierarchical wrinkles can be used as masters for replica molding in order to fabricate PMs with hierarchically wrinkled surfaces ( Figure 2D).…”

Durable and mass producible polymer surface structures with different combinations of micro–micro hierarchy

“…However, complicated structure design will lead to multiple time-consuming processing steps. Therefore, as a one-time fabrication method, the topdown method was usually used to fabricate pattern masters for further mass production with bottom up methods, such as molding [21,22].…”