Nanostructured surfaces

Self-organized plasma-assisted growth of micro- and nanosystems
Kosminska Yu.O., Perekrestov V.I.
Sumy State University, Rimskogo-Korsakova str., 2, 40007 Sumy, Ukraine
E-mail: y.kosminska@phe.sumdu.edu.ua

Modern progress in nanotechnology is based on the problem of formation of various micro- and nanostructures with novel structural and functional characteristics. Today there is an increasing attention paid by researches to search of self-organized physical, chemical, biological and technological processes that ensure formation of micro-and nanosystems. But for the present very limited number of possible variants of self-organized structure growth is known for deposition of metals, semiconductors and carbon by PVD techniques.
We report on novel approach to self-organized synthesis of micro – and nanostructures based on atom-by-atom deposition by sputtering under direct plasma action upon a growth surface. The main idea is interdependent dissipative self-organization of technological conditions and conservative self-organization of structures on a substrate. The main parameter that self-organizes is extremely low supersaturation of deposited vapors (~ 10-2 – 10-5) which play the role of the order parameter. The growth surface temperature can be considered as the conjugate field, and the substance flux as the control parameter. These three parameters together describe dissipative self-organization of functional character and are described by dynamical mathematical models. The steady-state low supersaturation is a prerequisite for conservative self-organization of structure growth.
Experimentally, this approach is realized in the form of quasi-equilibrium condensation by modified magnetron sputtering combined with hollow cathode in pure inert ambient under increased working gas pressure. A wide spectrum of possible micro- and nanostructures of metals, carbon and silicon beyond modern structure zone models has been obtained and their growth mechanisms have been studied. General character of the proposed approach has been shown by analyzing multiwall carbon nanotubes synthesis from anodic arc [1]. Thus, low-temperature plasma is a powerful active ambient to reveal self-organization of both technological deposition conditions and nanostructure formation mechanisms.

1.	Kosminska Yu.O., Perekrestov V.I. Regularities of self-organization of technological conditions during plasma-arc synthesis of carbon nanotubes // Diam. Rel. Mater.-2018.-85.-P. 37-48.