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The formation mechanisms of Ag- and Au-ordered structures on single-crystal silicon (Si) (111) and Si (110) surfaces were researched using high-resolution scanning tunneling microscopy method. It was shown that different patterns of self-assembled nanostructures with very precise and regular geometric shapes can be produced by controlling process parameters of thermal metal spraying on the substrate. The surfaces of nanorelieves at each stage of deposition were researched, and the main stages of morphological transformation were fixed.Self-ordered hexagonal pyramid-shaped nanostructures were formed at thermal deposition of gold on the Si (111), whereas only monolayer hexagonal formation could be observed on the plane Si (110). Gold monolayer flake nanostructures were obtained under certain technological parameters.Atomically smooth Ag film cannot be obtained on the Si (111) surface by means of thermal spraying at room temperature. The formation of two-dimensional (2D) clusters takes place; heating of these clusters at several hundred degrees Celsius leads to their transformation into atomically smooth covering.The weak interaction between Ag multilayer coatings and substrate was established that allows to clear crystal surface from metal with reproduction of the reconstructed Si (111) 7 × 7 surface by slight warming. The offered method can be used for single-crystal surface protection from destruction.

Методою високороздільчої тунельної мікроскопії досліджено наноутво-рення срібла на поверхні Si(111), яких одержано за допомогою термічного осадження у вакуумі. Встановлено, що срібло на поверхні кремнію може утворювати наноструктури, які складаються з атомарних площин. Мета-леві наноутворення можуть мати вигляд правильних шестикутників. Для даних структур мінімальна висота росту сходинки складає до 0,23 нм. Досліджено особливості трансформації нанорельєфу при зміні температу-ри зразка. Показано, що при збільшенні температури кількість відкритих шарів зменшується за рахунок поверхневого дрейфу, внаслідок якого від-бувається горизонтальне зміщення. Представлено можливість консерва-ції структури поверхні Si(111) 77.The silver nanostructures obtained by thermal vacuum deposition on the Si(111) surface are investigated by high-resolution tunnelling microscopy. As revealed, the silver on the silicon surface can form nanostructures consisting of atomic planes. Metallic nanoformations can take the shape of regular hexagons. For these structures, minimum height of the step growth varies up to 0.23 nm. Specific peculiarities of the nanorelief transformation with the sample-temperature increasing are detected as a result of horizontal displacement due to surface drift. The possibility of preserving of the Si(111) 77 structure is presented.Методом высокоразрешающей туннельной микроскопии исследованы нанообразования серебра на поверхности Si(111), полученные термиче-ским осаждением в вакууме. Установлено, что серебро на поверхности кремния может образовывать наноструктуры, состоящие из атомарных плоскостей. Металлические нанообразования могут иметь вид правиль-ных шестиугольников. Для данных структур минимальная высота роста ступени составляет до 0,23 нм. Исследованы особенности трансформации нанорельефа при повышении температуры образца в результате горизон-

Bismuth films are interesting objects for research because of the many effects occurring when the film thickness is less than 70 nm. The electronic band structure changes significantly depending on the film thickness. Consequently, by changing the film thickness, it is possible to control the physical properties of the material. The purpose of this paper is to give a brief description of the basic structural and physical properties of bismuth films. The structural properties, namely, morphology, roughness, nanoparticle size, and texture, are discussed first, followed by a description of the transport properties and the band structure. The transport properties are described using the semi-metal–semiconductor transition, which is associated with the quantum size effect. In addition, an important characteristic is a two-channel model, which allows describing the change in resistivity with temperature. The band structure of bismuth films is the most interesting part due to the anomalous effects for which there is still no unambiguous explanation. These effects include anomalous spin polarization, nontrivial topology, and zone changes near the edge of the film.

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