MOSCOW, 15 January. /TASS/. In a joint study, scientists from the MIPT (Moscow Institute of Physics and Technology), ICP (Institute of Chemical Physics) named after Semenov, MSU (Moscow State University) and IPCP (Institute of Problems of Chemical Physics) have developed a mechanism of laser deposition of patterns on glass with a resolution of 1000 times lower than the diameter of a human hair said in a press release on Friday.
“This mechanism allows inexpensively and relatively easy to apply complex patterns to a glass surface, whereby obtaining a spatial resolution of less than 100 nanometers”, the institute said.
The whole process of nanoengraving appears as follows. Initially, the glass surface is irradiated with a femtosecond laser. The laser pulse is focused by means of a glass bead, which is guided by an optical "trap" to a predetermined area of the glass. As a result, wide hillocks are formed on the surface of glass; but then, after surface treatment with an alkaline solution, these hillocks are converted to smaller craters of more streamlined shapes. (see Figure 1)
A femtosecond laser used by scientists allows deposition of complex two- and three-dimensional patterns on the surface of transparent materials. Resolution - the minimum size of the pattern’s image detail - is always a problem in these kinds of tasks, since it is limited (for physical reasons) by the laser wavelength. The higher the resolution, the smaller the size of patterns applied and the more interesting and sought-after these patterns in technology.
The minimum width of the crater obtained was 70 nm (see Figure 2). Also, o demonstrate this method, the abbreviation of the Institute of Chemical Physics (ICP) was deposited on glass with a high resolution (about 100 nanometers) (see Figure 3). The average width of each letter is 100 nm, depth - 20 nm.
Nanoengraving is used to create ultra-precise circuits in microfluidics. The operating fluid can flow through the engraved channels connecting various parts of the circuit; and the smaller the size of such a circuit, the higher the engraving resolution. The paper describing the method was published recently in the journal ACS Applied Materials&Interfaces (A. Shakhov, A. Astafiev, A. Gulin and V. Nadtochenko, Femtosecond Nanostructuring of Glass with Optically Trapped Microspheres and Chemical Etching, ACS Appl. Mater. Interfaces, 2015, 7 (49), pp 27467–27472).