Nanowires / Nanoobjects

Nanowires by metal-assisted etching

Abstract People Publications

Metal-assisted etching is a fabrication method for highly ordered and vertically aligned arrays of silicon nanowires and silicon nanowires containing a Si/Ge superlattice. This top-down approach uses different methods to cover the substrate with a patterned metal film and a subsequent etching step in HF/H₂O₂. There are three methods available to structure the substrate: colloidal lithography, reactive ion etching through anodized aluminum oxid membranes and laser interference lithography, each of which is explained in more detail in the links given.

With these methods arrays of nanowires with hexagonal or square symmetry and adjustable diameters ranging from about 10 nm to several µm can be fabricated. High area densities of 10¹⁰ wires/cm², control of diameter, length and position of the wires are possible.

Beside the formation of these nanowires, another main aspect of our research work deals with the investigation of the etching process itself. A better understanding of the etching reaction allows a controlled fabrication not only of nanowires, but also of nanopores.