Nanocomposites and nanomaterials
Application of inorganic resists for the formation of nanosized relief structures
A.A. Kryuchyn1, Petrov V.V.1, Rubish V.M.1, Trunov M.L.1, Beliak Ie.V.1
1 Institute for Information Recording of the NAS of Ukraine
Shpaka, 2, Kyiv-03113, Ukraine. 
E-mail: kryuchyn@ipri.kiev.ua

Inorganic resists have high resolution, which allows them to form elements that are smaller than the resolution of conventional diffraction-limited optical focusing systems [1-3]. The key interest is in the problem on the formation of the elements with sizes significantly lower than the values determined by the light diffraction limit. The solution of this problem is largely determined by the type of inorganic resist. The inorganic resists based on thin films of chalcogenide vitreous semiconductors have great potential for recording of sub-micron sizes of elements by optical radiation.
Earlier studies have shown that the resolving power of the recording materials based on the thin films of chalcogenide vitreous semiconductors is much higher than resolution of conventional diffraction-limited optical focusing systems . There are some ways for creation of sub-micron sizes of elements on the thin films of chalcogenide vitreous semiconductors [3-5].
Near-field optical recording techniques can be used to record such elements, but they do not allow recording speeds greater than 10 mm / sec. For most practical reasons, such speeds are not sufficient. Numerous proposals to increase the optical transmission of near-field optical probes have not yet been implemented, although intense research is being conducted in this direction. The most promising direction is the use of microstrip structures [1, 6, 7]
The process creation of sub-micron sizes of elements on the thin films of chalcogenide vitreous semiconductors process can be realized using nonlinear exposure characteristics of chalcogenide glass semiconductor films or better threshold exposure characteristics [2, 8]. Our experimental studies have shown the possibility of obtaining elements of 150-200 nm, which is 5-6 times smaller than the size of the irradiated zone [2, 9]. The limitation in the use of the thermo- lithographic recording method consists in the need for very precise stabilization of the energy of the recording pulses [2, 9]. 
Significant reduction in the size of the elements recorded by the laser beam on the films of the of chalcogenide glass transition semiconductors can be achieved by realization the modification of their structure for localization of exposing light to dimensions below the diffraction-limited area. Appropriate conditions can be created using excitation of the plasmon resonance in nanoparticles of noble metals embedded into the chalcogenide glass semiconductor matrix. In our opinion, this approach is most promising for the formation of a focused optical radiation of nanosized structures on inorganic resin films based on chalcogenide semiconductors [2, 10]. 

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