The possibility of using chemical vapor deposition (CVD) graphene as a 2D buffer layer for epitaxial growth of III-nitrides by plasma assisted-MBE on amorphous substrates (SiO ₂ prepared by thermal oxidation of Si wafer) was investigated. The comparative study of graphene-coated parts of the wafers and the parts without graphene was carried out by scanning electron microscopy and X-ray diffractometry. It was shown that epitaxial GaN and AlN films with close to 2D surface morphology can be obtained by plasma assisted-MBE on amorphous SiO ₂ substrates with a multilayer graphene buffer using the HT AlN nucleation layer.

Nanostructured diamonds hosting optically active paramagnetic color centers (NV, SiV, GeV, etc.) and hyperfine-coupled with them quantum memory ¹³C nuclear spins situated in diamond lattice are currently of great interest to implement emerging quantum technologies (quantum information processing, quantum sensing and metrology). Current methods of creation such as electronic-nuclear spin systems are inherently probabilistic with respect to mutual location of color center electronic spin and ¹³C nuclear spins. A new bottom-up approach to fabricate such systems is to synthesize first chemically appropriate diamond-like organic molecules containing desired isotopic constituents in definite positions and then use them as a seed for diamond growth to produce macroscopic diamonds, subsequently creating vacancy-related color centers in them. In particular, diamonds incorporating coupled NV-¹³C spin systems (quantum registers) with specific mutual arrangements of NV and ¹³C can be obtained from anisotopic azaadamantane molecule. Here we predict the characteristics of hyperfine interactions (hfi) for the NV-¹³C systems in diamonds grown from various isotopically substituted azaadamantane molecules differing in ¹³C position in the seed, as well as the orientation of the NV center in the post-obtained diamond. We used the spatial and hfi data simulated earlier for the H-terminated cluster C₅₁₀[NV]^-H₂₅₂. The data obtained can be used to identify (and correlate with the seed used) the specific NV-¹³C spin system by measuring, e.g., the hfi-induced splitting of the m_S = ±1 sublevels of the NV center in optically detected magnetic resonance (ODMR) spectra being characteristic for various NV-¹³C systems.

Silicon carbide thin films were obtained on Si (100) and (111) substrates by means of vacuum laser ablation of α-SiC ceramic target. The influence of substrate temperature on composition, structure and surface morphology of experimental samples was examined using Rutherford backscattering spectrometry (RBS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), conventional and high-resolution transmission electron microscopy (TEM/HRTEM), atomic force microscopy (AFM), selected area electron diffraction (SAED) and X-ray diffraction (XRD) methods.

We demonstrate the growth features of III-nitrides on graphene buffer layers obtained by the CVD method on a copper catalyst with different dominant grain orientations. The reflection high-energy electron diffraction technique (RHEED) is used to map the 2D reciprocal space structures of graphene buffers and growing nitride layers. The RHEED reciprocal space pattern for the graphene layer grown on a (111) textured copper foil and transferred to a SiO₂/Si substrate demonstrates the sixfold symmetry characteristic of a highly oriented material. In turn, graphene grown on a Cu (100) foil consists of two types of domains that are 30° rotated relative to each other. It has also been demonstrated that III-nitride films exactly repeat the texture of the 2D graphene buffers. The GaN sample grown over the highly textured substrate demonstrates a clear sixfold symmetry of the RHEED reciprocal space map as well as $\{10\overline{1}3\}$ XRD pole figure, which is close to 2D surface morphology. In turn, the GaN film grown over the graphene buffer layer transferred from the Cu (100) textured foil has 12-fold axial symmetry, which is equivalent to the essentially two-domain in-plane orientation of the initial graphene.

The results of this study quantitatively and qualitatively illustrate the processes of mismatch stress relaxation upon epitaxy of cubic silicon carbide on silicon. The mechanical stress distribution in 3C–SiC/Si and 3C–SiC/por-Si heterostructures is analyzed. It is shown that a porous buffer layer plays a role in the reduction of mismatch stress. The data of the theoretical study are verified by experimental residual stress in 3C–SiC/Si and 3C–SiC/por-Si samples.

Single-layer (SLG)/few-layer (FLG) and multilayer graphene (MLG) (>15 layers) samples were obtained using the CVD method on high-textured Cu foil catalysts. In turn, plasma-assisted molecular beam epitaxy was applied to carry out the GaN graphene-assisted growth. A thin AlN layer was used at the initial stage to promote the nucleation process. The effect of graphene defectiveness and thickness on the quality of the GaN epilayers was studied. The bilayer graphene showed the lowest strain and provided optimal conditions for the growth of GaN/AlN. Theoretical studies based on the density functional theory have shown that the energy of interaction between graphene and AlN is almost the same as between graphite sheets (194 mJ/m²). However, the presence of vacancies and other defects as well as compression-induced ripples and nitrogen doping leads to a significant change in this energy.