Focused-ion-beam-assisted fabrication of polymer rolled-up microtubes

Abstract

A focused ion beam (FIB) has been applied to the fabrication of polymer microtubes via the rolling-up technique from poly(4-vinyl pyridine)/polystyrene bilayer films deposited on the top of a sacrificial aluminum layer covering a silicon wafer. The bending forces in the film arise due to different swelling of the bilayer components in acidic water and lead to rolling of the film. The dimensions and position of the rolled-up tubes can be controlled by FIB milling (sputtering) of geometrically well-adjusted openings in the polymer films. This technique can be applied to the structuring of scrolled films formed from different materials without the use of lithographically patterned photoresists. The geometrical patterning of the tube interior can also be done by FIB irradiation.

Self‐Rolled Polymer Tubes: Novel Tools for Microfluidics, Microbiology, and Drug‐Delivery Systems

“…The diameter of the formed tubes has been found to depend on both the ratio between the thicknesses of the polymer layers, as well as on the dose or irradiation level18 ( Table 1 ). Single tubes with exactly defined lengths can also be formed by focused ion‐beam patterning of the bilayer films 19…”

Polymer Tubes by Rolling of Polymer Bilayers

“…Our approach is based on use of thin polymeric bilayers deposited on a substrate [8][9] . The rolling of tube is provided by the bending moment due to swelling properties of chemically dissimilar polymers in selective solvents (Figure 1).…”

Micromanipulation using artificial bacterial flagella

“…For the experiments, the InGaAs/GaAs/Cr trilayer has a thickness of 11/16/15 nm, the ribbon width is 1.8 μm, and the diameter of the as-fabricated ABF is 2.8 μm. Different materials are candidates for helical tail fabrication, including semiconductors, metals, and polymers [17,[20][21][22][23]. The soft-magnetic metal head is in the shape of a thin square plate with dimensions of 4.5 μm (length) × 4.5 μm (width) × 200 nm (thickness).…”