Self-rolled polymer microtubes with engineered hidden walls

Micro and nanotubes are manufactured by self-rolling of thin bilayer polymer films (polystyrene/poly(4-vinyl pyridine, PS/P4VP) gradually released from a solid substrate. Swelling of the P4VP layer in acidic water opposed by a stiff PS layer leads to rolling of the film into tubings of micrometer diameters. The position and the arrangement of the tubes on the substrate are defined by UV photolithography structuring of the polymer film. A few nanometer thick metallic patterns, such as arrays of conductive stripes and simple electrical circuits, are formed on the top of the polymer film by magnetron sputtering and transferred to the tube interior by rolling. Intra-tubular rolled-up microsolenoids are applied to generation of localized magnetic fields inside the tubes and in their vicinity.