NSU Scientists Develop Special Anti-Reflective Coatings

Researchers at the NSU Physics Department’s Analytical and Technological Research Center (ATRC NSU PD) "High Technologies and Nanostructured Materials" have created anti-reflective coatings from germanium nanodisks in an indium-tin oxide layer. This new type of coating has the properties of metasurfaces with special optical properties. They are used in photoelectric converters such as those in solar cells and photodetectors.

Alexander Shklyaev, Head Researcher at the ATRC NSU PD Laboratory of Functional Diagnostics of Low-Dimensional Structures for Nanoelectronics, Chief Researcher at the Laboratory of Nanodiagnostics and Nanolithography, Rzhanov Institute of Semiconductor Physics SB RAS, and Doctor of Physical and Mathematical Sciences, provided more details about their work,

Metasurfaces are usually created in the form of coatings made of metal or dielectric nanoparticles. We used germanium that has a high refractive index as a dielectric that is fundamentally important. Coatings made of germanium nanoparticles not only serve as anti-reflective coatings, but, more importantly, change the direction of passing light, directing a significant part of it along the surface and at small angles to it. We have manufactured samples with this coating and for the first time quantitatively investigated the directions of scattered light propagation.

Anti-reflective coatings made of compact dielectric particles do not cover the surface completely, leaving most of it open. This shape indicates their potential for use in photochemistry. The possibility of increasing excited surface states during light absorption increases the rates of chemical reactions in photochemical processes, in particular, in catalysis.

Shklyaev continued,

Now we have to use specific examples of solar cells and photodetectors to demonstrate that the use of the anti-reflective coatings we create really leads to an improvement in the characteristics of these devices. It would also be important to study the course of photochemical reactions using these coatings to determine whether their efficiency increases.

This research is conducted in collaboration with the Rzhanov Institute of Semiconductor Physics SB RAS and is supported by the Russian Science Foundation grant No. 23-72-30003.