Researchers build miniature optical antennas using DNA as a guide

Researchers have developed a new fabrication technique that combines programmable DNA origami shapes and conventional lithography methods to create metallic nanoantennas and chiral shapes for diverse applications.

Research groups from Aalto University and University of Jyväskylä together with researchers from California Institute of Technology (Caltech, USA) and Aarhus University (iNANO Center, Denmark) have developed a new technique to fabricate precise metallic nanostructures with designed plasmonic properties by means of different self-assembled DNA origami shapes. The so-called DALI (DNA-assisted lithography) method has been published in the latest issue of Science Advances.

Video: M. Kostiainen and V. Linko

The trick in the DALI method is that when the DNA structures are deposited on a chip coated with silicon, silicon oxide can be selectively grown only on the bare areas of the substrate.

“We can build virtually any nanoscale shape using a DNA origami technique, and now we have shown how to use these accurate shapes as “stencils” to create millions of fully metallic nanostructures with 10 nm feature sizes in one go”, explains Adjunct Professor Veikko Linko from Aalto University.

As the DALI method is highly parallel, researchers think that it could further enable cheap wafer-scale production of surfaces as it does not rely on costly patterning methods. In the future, the miniature antennas could be utilized in various optical and plasmonic applications, such as biosensing or fluorescence enhancement.

Read the full story on the Aalto University website

Original publication: Plasmonic nanostructures through DNA-assisted lithography Science Advances, volume 4, issue 2, eaap 8978 (February 2, 2018)