  Three-dimensional self-assembly of lithographically patterned ultrathin films
opens a path to manufacture microelectronic architectures with functionalities
and integration schemes not accessible by conventional two-dimensional
technologies. Among other microelectronic components, inductances,
transformers, antennas and resonators often rely on three-dimensional
configurations and interactions with electromagnetic fields requiring
exponential fabrication efforts when downscaled to the micrometer range. Here,
the controlled self-assembly of functional structures is demonstrated. By
rolling-up ultrathin films into cylindrically shaped microelectronic devices we
realized electromagnetic resonators, inductive and mutually coupled coils.
Electrical performance of these devices is improved purely by transformation of
a planar into a cylindrical geometry. This is accompanied by an overall
downscaling of the device footprint area by more than 50 times. Application of
compact self-assembled microstructures has significant impact on electronics,
reducing size, fabrication efforts, and offering a wealth of new features in
devices by 3D shaping.
