Nanotechnology for
smart applications and
Energy Efficiency
NanoFab Tools S.L. is a Spanish R&D SME dedicated to innovative nanotechnology solutions for smart applications and energy efficiency using advanced patterning and coating techniques.
The science behind our products
Interference Lithography (IL) takes advantage of the wave-like nature of light, which allows for an interference pattern to be created using two or more coherent light waves. The interference pattern can be used to expose a light sensitive polymer, and after development, a nanostructure is formed in the polymer.
Figure 1. Schematic showing how two coherent light waves interact to form a grating in a photosensitive polymer on top of a substrate.
The period (P) of the grating is defined by the vacuum wavelength of the exposing light, the angle of intersection of the beams, and by the refractive index n of the medium in which the interference takes place. For n=1:
The basic concept of IL is simple, but the system configuration can vary significantly depending on the required pattern specification. Figure 2 below shows three different IL system set-ups, including (a) the Mach- Zehnder, (b) the Lloyds mirror and (c) using a grating mask.
Figure 2. Illustrations of different types of IL systems including (a) Mach-Zehnder, (b) Lloyds mirror and (c) using a grating mask.
Interference lithography is a maskless patterning technique that allows generating periodic structures with periods between 100nm to 100μm in a parallel process.
The nanopatterned surfaces can be produced over large areas (up to ~ 5000 cm2) using short exposures and processing times, which makes this technique appealing for high-volume nanostructure manufacturing.
Using IL a range of different materials can be nanopatterned including ceramics, metals and plastics.
The benefits of IL processing for high volume nanomanufacturing are that it is:
  • Maskless
  • A parallel process
  • Fast
  • Convenient
  • Cost effective
  • Accurate
Examples of the types of nanostructures that can be produced are shown below: