GaAs nanowires on Si nanopillars: towards large scale, phase-engineered arrays.

Large-scale patterning for vapor-liquid-solid growth of III-V nanowires is a challenge given the required feature size for patterning (45 to 60 nm holes). In fact, arrays are traditionally manufactured using electron-beam lithography,for which processing times increase greatly when expanding the exposure area. In order to bring nanowire arrays one step closer to the wafer-scale we take a different approach and replace patterned nanoscale holes with Si nanopillar arrays.

SiGe quantum dot crystals with periods down to 35 nm.

By combining extreme ultraviolet interference lithography with Si/Ge molecular beam epitaxy, densely packed quantum dot (QD) arrays with lateral periodicities down to 35 nm are realized. The QD arrays are featured by perfect alignment and remarkably narrow size distribution. Also, such small periodicities allow the creation of three-dimensional QD crystals by vertical stacking of Si/Ge layers using very thin Si spacer layers.

Displacement Talbot lithography: a new method for high-resolution patterning of large areas.

Periodic micro and nano-structures can be lithographically produced using the Talbot effect. However, the limited depth-of-field of the self-images has effectively prevented its practical use, especially for high-resolution structures with periods less than 1 micrometer. In this article we show that by integrating the diffraction field transmitted by a grating mask over a distance of one Talbot period, one can obtain an effective image that is independent of the absolute distance from the mask.

Titania-assisted electron-beam and synchrotron lithography.

Novel imaging layer technology for electron-beam and extreme-ultraviolet lithographic processes based upon generation of Pd nanoparticles in the Pd(2+)-loaded TiO(2) films was developed. The electroless metallization of the patterned TiO(2):Pd(2+) films yields both negative and positive nickel images with resolution down to approximately 100 nm.

Three-dimensional Si/Ge quantum dot crystals.

Modern nanotechnology offers routes to create new artificial materials, widening the functionality of devices in physics, chemistry, and biology. Templated self-organization has been recognized as a possible route to achieve exact positioning of quantum dots to create quantum dot arrays, molecules, and crystals. Here we employ extreme ultraviolet interference lithography (EUV-IL) at a wavelength of lambda = 13.