Novel cost-effective nanoimprint lithography method improves ordering in periodic arrays from BCPs

May 30, 2014

Block copolymers (BCPs) are the most attractive alternative to date for the fabrication of well-defined complex periodic structures with length scales below 100 nm. Such small structures might be used in a wide range of technological applications but current available methods are very expensive, especially when those structures present length scales under 20 nm. 

A work led by the Institut Català de Nanociència i Nanotecnologia (ICN2) Phononic and Photonic Nanostructures Group suggests a new method to produce hexagonal periodic arrays with high fidelity while reducing time and costs. ICREA Research Professor Dr Clivia M. Sotomayor Torres and Dr Claudia Simão conducted, together with the authors listed below, a work published in the latest issue of Nanotechnology and featured cover article. 

The methodology consists on in situ solvent-assisted nanoimprint lithography of block copolymers, a technique which combines a top-down approach - nanoimprint lithography - with a bottom-up one - self-assembled (bottom-up). The process is assisted with solvent vapors to facilitate the imprint and simultaneous self-assembly of high Flory-Huggins parameter BCPs, the ones that yield sub-15 nm size features, in what has been called solvent vapors assisted nanoimprint lithography (SAIL).

SAIL is a scalable technique which has shown its efficiency over a large area of up to 4 square inches wafers. The resulting sample was analysed using different methods, including field emission scanning electron microscopy (FE-SEM) and grazing-incidence small-angle x-ray scattering (GISAXS). The latter was performed at the Diamond synchrotron light source (UK) and allowed characterisation of structural features of the nanostructured polymer surfaces. It is the first time that GISAXS has been used to analyse a direct-nanoimprint BCP sample.

The results obtained with SAIL demonstrated an improvement in ordering of the nanodot lattice of up to 50%. It is a low cost, scalable and fast technique which brings self-assembled BCPs closer to their industrial application. These versatile materials are very interesting for applications such as storage devices, nano-electronics, low-k dielectrics or biochemical applications. 

Explore further: A new approach to engineering the materials of the future

More information: Claudia Simão, Worawut Khunsin, Nikolaos Kehagias, Mathieu Salaun, Marc Zelsmann, Michael A Morris, and Clivia M Sotomayor Torres. Order quantification of hexagonal periodic arrays fabricated by in situ solvent-assisted nanoimprint lithography of block copolymers. Nanotechnology. 25, 175703 (2014). DOI: 10.1088/0957-4484/25/17/175703

add to favorites email to friend print save as pdf

Related Stories

More precise method of nanopatterning

Aug 04, 2011

“A nanoimprint method has already been achieved in nanopatterning with a high resolution using negative type photoresist,” Kosei Ueno tells PhysOrg.com. Ueno is a scientist at Hokkaido University in Sapporo, Japan, ...

Scientists develop 3D SEM metrology for 10nm structures

Mar 24, 2014

(Phys.org) —PML researchers have devised an idea for determining the three-dimensional shape of features as small as 10 nanometers wide. The model-based method compares data from scanning electron microscope ...

Recommended for you

Bacterial nanowires: Not what we thought they were

Aug 18, 2014

For the past 10 years, scientists have been fascinated by a type of "electric bacteria" that shoots out long tendrils like electric wires, using them to power themselves and transfer electricity to a variety ...

Towards more efficient solar cells

Aug 13, 2014

A layer of silicon nanocrystals and erbium ions may help solar cells to extract more energy from the ultraviolet (UV, high-energy) part of the solar spectrum. Experimental physicists from the FOM Foundation, ...

User comments : 0