This paper presents an analysis of studies devoted to the formation of thin films on quasi-periodic substrates. The atomistic structure of quasi-crystalline surfaces is considered in detail, and parallels with models of volumetric structure are drawn. Various systems where experiments on the creation of thin layers were previously conducted are analyzed.
The emphasis is on the mechanisms of initiation of thin film growth, on the methods of their formation, depending on the properties of the deposited metals, on the probability of mixing or doping in the boundary region, as well as on the epitaxial relationships arising at the interface between crystalline and quasicrystalline materials.
In addition, cases where precipitated elements form a quasi-periodic structure are considered. This opens up prospects for a deeper understanding of the relationship between quasi-periodicity and the physical properties of complex solids, which differ in both structural and chemical complexity.
Epitaxial growth of thin films on substrates is a fundamental process in materials science and nanotechnology, allowing the creation of heterostructures with specified properties. The use of quasicrystals as substrates, materials with a unique aperiodic atomic structure, opens up new horizons in the formation of films with unusual characteristics.
One of the key features of epitaxial growth on quasi-crystalline substrates is the influence of the aperiodic structure of the substrate on the structure and properties of the grown film. Unlike traditional epitaxial growth on crystalline substrates, where strict copying of the lattice occurs, complex patterns are formed on quasi-crystals, reflecting the long-range orientational order of the substrate. This can lead to the formation of films with new phases, increased defectiveness or unique electronic properties.
In addition, the aperiodic structure of quasicrystals affects the kinetics of film growth. Adsorption of atoms on the surface of a quasicrystal occurs unevenly, which leads to the formation of nanoclusters and complex surface morphology. Control of growth conditions, such as substrate temperature, deposition rate, and atmospheric composition, allows one to control the structure and properties of the films being formed.
Studies of epitaxial growth on quasicrystalline substrates open up prospects for creating new materials with unique properties, such as increased hardness, low friction coefficient, and unusual optical properties. These materials can find application in various fields, including microelectronics, sensors, and catalysis.
Author: V Fournée and P.A. Thiel
Institute: Department of Materials Science, Defence Institute of Advanced Technology, Pune, 411025, Maharashtra, India