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Methods of synthesis and diagnostics

  1. 1. Technique of the surface cleaning of monocrystals of refractory and transition metals up to atomic cleanliness during realization of R & D

    This technique describes the operations of cleaning of monocrystals of refractory metals by high-temperature "flash" and monocrystals of transition metals by ion etching in ultrahigh vacuum conditions.

  2. 2. Technique of permanent deposition of different metals with a continuous control of the thickness of deposited layers during realization of R & D

    This technique is based on a experimental registration of manifestations of quantum size effects in thin layers on the surface of metal monocrystals continuously for increasing the thickness of the deposited film, starting from submonolayer thicknesses, with using the method of photoelectron spectroscopy with angular resolution (ARPES). The film thickness can be measured with an accuracy of a few tenths of a monolayer and controlled based on the observed spectrum of the quantum electronic states by analysing their energy and quantity. This technique can be used in the manufacture of precision quantum nanoelectronic devices and new nanostructured materials.

  3. 3. Technique of testing of the crystal structure of monocrystal surfaces and their orientation for researches by method of photoelectron spectroscopy with angular resolution by high-resolved details of LEED patterns during realization of R & D

    LEED is widely used to study of the crystal structure of single crystal surfaces in ultrahigh vacuum conditions. Information about the structure of the surface is obtained by analyzing the elastically scattered electrons by the crystal, and this leads to the conclusion about perfection of the crystal structure of the sample, the orientation of the crystallographic axes in space. This information is necessary for the proper orientation it in the right direction for further crystallographic study of dispersion of the energy bands along the preferred directions of the surface Brillouin zone with high symmetry by photoelectron spectroscopy with angular resolution (ARPES). This technique reduces the time required for characterization and orientation of single crystal surface or low-dimensional structures formed on its surface.

  4. 4. The technique of measuring of the dispersion of the energy band structure and occupied and unoccupied state by the photoelectron spectra with high angular and energy resolution during realization of R & D

    Using this technique provides a unique opportunity to receive information about the electronic energy structure and the corresponding dispersion dependences of the electronic states of the valence band of the objects. These possibilities become particularly important in the study of the processes of the formation and analysis of the electronic properties of nanostructured low-dimensional objects of 2D- and 1D-type, where there is a substantial modification of the electronic structure of the valence states due to quantum size effects. Such modification allows to create objects with a fundamentally new type of electronic structure (which can be modified in a controlled manner) and, consequently, leads to radically new electronic properties of created objects. Therefore, it is very important to have the opportunity to study and control the electronic structure and the dispersion of the electronic states in the required direction of the Brillouin zone, where there are dimensional constraints of the wave functions of nanosystem.

  5. 5. Technique of elemental and chemical analysis of solids by the method of photoelectron spectroscopy of core levels

    Photoelectron spectroscopy allows to determine  binding energy of core levels in solids. Each element has its own set of energies of core levels (alike a "fingerprint"), herewith energy of core levels, corresponding to different elements, quite well energetically separated. This technique allows to identify various elements by the photoelectron spectra, i.e., get information about elemental composition of investigated system. By defining energy peaks in the photoelectron spectra it is possible to get information not only about atoms of which elements are located at the solid surface, but also in which are they chemical state. The formation of chemical bonds between atoms of a solid body, accompanied by a redistribution of the electron density, can lead to a change in the energy of electrons that will, certainly, appear in the change of kinetic energy of photoelectrons.

  6. 6. Technique of the raster depth profiling

    Study of the distribution of elements over the depth is carried out using the technique of a raster ion profiling. Essence of a technique is the following: investigated surface alternately etched with argon ions and study by XPS. The result is a set of photoelectron spectra at different time of surface etching. Etching time determines the thickness of sputtered layer. For example, calibration using an atomic force microscope provides a quantitative relation between depth and time of etching.

  7. 7. Technique of synthesis of graphene by chemical vapor deposition

    This technique allows to synthesize one-domain graphene on surface of thin monocrystal layers of nickel and cobalt.