DNA origami is the basis of a new technology for high-precision and high-speed lithography

A research team from Aalto University, Finland, California Institute of Technology, USA, and Aarhus University, Denmark, has developed a new lithographic technology that allows the simultaneous production of multiple metallic nanostructures with specified optical and plasmonic properties. The key to this technology is a DNA self-assembly technology called DNA origami. And it is precisely because of this that the new technology was named DALI (DNA-assisted lithography).

“Using the DNA origami technique, we can create virtually any nanoscale shape and use this highly precise shape as a stencil to create millions of completely identical metallic nanostructures, which can be as small as 10 nanometers,” explains Veikko Linko, researcher from Aalto University.

In this technology, DNA blanks are deposited on the surface of a chip covered with a transparent silicon layer. “By controlling the process of further transformation of DNA, we can leave open areas of the surface, which will later be coated with a layer of silicon dioxide. And this layer can be used as a mask for further steps of the lithography process “- says Veikko Linko, -” Finally, evaporating a layer of metal deposited on a transparent base from sapphire through this mask, for example, we will get metal nanostructures, exactly repeating the shape and size of the structures formed by DNA molecules at the previous stages. “

This method makes it possible to cover large surfaces with the same metal nanostructures, due to which these surfaces acquire unusual and amazing optical properties. Small changes in the shape and size of these nanostructures allow such surfaces to work effectively over a wide range, including the range of visible light. “As an example, we created a surface covered with optical antennas in the shape of a bow tie. This antenna shape allows the surface to operate efficiently in a very wide range of light, from infrared to visible, “says Jussi Toppari, a scientist at Aarhus University.” These surfaces, covered with tiny optical antennas, can be used in a wide variety of optical and plasmonics, including Raman spectroscopy, for example. “

“DALI technology is highly versatile and scalable. It can provide inexpensive large-scale production of optical surfaces of any size, which until recently were created only by sequential creation and copying of individual elements “- says Professor Mauri Kostiainen, -” In the future, such surfaces may become the basis of various types of sensors. new biomedical devices, invisibility cloak metamaterials and much more. ”Sou

rce: dailytechinfo.org