Fig 1 - uploaded by Malgorzata Sznajder
Content may be subject to copyright.
Source publication
We present studies of the morphology and charge distribution at the 4H-SiC/wz-GaN heteropolar junctions. Our investigations are based on the first principles calculations in the framework of the density functional theory where the interfaces between the SiC substrate and GaN layers are represented by means of a slab. These studies reveal possible c...
Contexts in source publication
Context 1
... are kept xed in order to mimic the behavior of bulk material, while the atoms of eight middle layers of each material are relaxed until forces acting on them converge to less than 0.02 eV/Å. We consider four types of interfaces, namely, CGa, CN, SiGa, and SiN, as characterized by the long bonds across the interface, and depicted schematically in Fig. 1. The tetrahedral coordination of the nearest-neighbor atoms is also indicated ...
Context 2
... it can be seen in Fig. 1, the abrupt interfaces of the type CGa and SiGa possess undersaturated long bonds between C (or Si) and Ga atoms. Indeed, a tetra- hedrally coordinated Ga atom shares four bonds with its nearest neighbors, having, however, only three valence electrons to form four bonds, whereas, the C atom (of valency IV) contributes four electrons to ...
Context 3
... that replacement of an atom with valency V (N) by C or Si (of valency IV) would lead to a deciency of three quarters of electron per one bond type presented in Fig. 1. Similarly, replacement of an atom with valency III (i.e., Ga) by C or Si (both with valency IV) would lead to an access of 3/4 electrons per bond. Hence, in the case of CN (SiN) interfaces, one (out of four) N atoms in the lateral 2 × 2 unit cell should be replaced by one Si (or C) atom. By analogy, the SiGa (CGa) interfaces can be ...
Similar publications
Recent advances in controlled synthesis of graphene nanodevices urge the understanding of various defects’ effect on the electronic transport properties, such as Stone-Wales defects, single vacancy, double vacancies and multiple vacancy chains. In this work, we systematically investigated these defects in single-layer graphene, by using first princ...
C4F7N, C5F10O, etc., as new environmental-friendly alternative gases decompose under partial discharge and produce a series of products such as CO, CF4, C2F6, C3F8, CF3CN, C2F5CN, and COF2. Based on the first-principles calculation method of density functional theory (DFT), the adsorption characteristics of intrinsic state graphene and Mo-doped gra...
We investigate the morphology and charge distribution at the (001)-diamond/BN heteropolar junctions of the cubic materials. Our investigations are based on the first principles calculations in the framework of the density functional theory. These studies reveal that reconstruction of the interface leads to possible charge compensation at the interf...
The thermodynamic properties and elasticity of superhydrous phase B (ShyB) at high pressure and temperature are calculated using first principles calculations based on density functional theory. The velocities and densities of ShyB are significantly lower than those of bridgmanite and periclase, the major minerals in the lower mantle. The anisotrop...
The structural and temperature reliance manner of the thermodynamic parameters of Ni–Al intermetallic compounds with different pressures is comprehensively studied by executing first-principles calculation using the density functional theory (DFT). The calculated optimized volume and bulk modulus are in good agreement with the experimental and theo...
Citations
... In the present work we analyze reconstructions occurring both in the substrate interface layer and in the interface layer of the material grown in [001] and [111] directions. To enable a comparison of our results with those presented already for other nitrides grown on carbon or silicon carbon substrate [8,9], we decrease the lateral unit cell to 2 × 2 size and utilize both the non-stoichiometric superlattice and isolated slab models. ...
... The cut-off of 400 Ry is used for the real space mesh. The Brillouin zone integrations are performed by means of the (11,11,11) and (9,9,9) k-points meshes for bulk diamond and boron nitride crystals, respectively, as well as the (5,5,1) one for superlattice calculations. The above chosen numerical parameters lead to a good agreement between numerical and experimental values of lattice constants for the bulk diamond a 0 = 3.5864 Å, and bulk c-BN a 0 = 3.6150 Å (experimental values diamond: 3.5668 Å and c-BN: 3.615 Å [13]). ...
... The cut-off of 400 Ry is used for the real space mesh. The Brillouin zone integrations are performed by means of the (11,11,11) and (9,9,9) k-points meshes for bulk diamond and boron nitride crystals, respectively, as well as the (5,5,1) one for superlattice calculations. The above chosen numerical parameters lead to a good agreement between numerical and experimental values of lattice constants for the bulk diamond a 0 = 3.5864 Å, and bulk c-BN a 0 = 3.6150 Å (experimental values diamond: 3.5668 Å and c-BN: 3.615 Å [13]). ...
... The cutoff of 400 Ry is used for the real space mesh. The Brillouin zone integrations are performed by means of the (11,11,11) and (9,9,9) k-points meshes for bulk diamond and boron nitride crystals, respectively, as well as the (5,5,1) one for superlattice calculations. The diamond and zinc-blende (c-BN) nitride crystals are represented by cubic supercells that are repeated periodically in space. ...
... The cutoff of 400 Ry is used for the real space mesh. The Brillouin zone integrations are performed by means of the (11,11,11) and (9,9,9) k-points meshes for bulk diamond and boron nitride crystals, respectively, as well as the (5,5,1) one for superlattice calculations. The diamond and zinc-blende (c-BN) nitride crystals are represented by cubic supercells that are repeated periodically in space. ...
... The cutoff of 400 Ry is used for the real space mesh. The Brillouin zone integrations are performed by means of the (11,11,11) and (9,9,9) k-points meshes for bulk diamond and boron nitride crystals, respectively, as well as the (5,5,1) one for superlattice calculations. The diamond and zinc-blende (c-BN) nitride crystals are represented by cubic supercells that are repeated periodically in space. ...
We investigate the morphology and charge distribution at the (001)-diamond/BN heteropolar junctions of the cubic materials. Our investigations are based on the first principles calculations in the framework of the density functional theory. These studies reveal that reconstruction of the interface leads to possible charge compensation at the interface and increases also the stability of the junction in comparison to the abrupt interfaces.
The morphology, charge distribution, and stability of interfaces in the diamond/c-BN and 3C-SiC/ zb-GaN heteropolar junctions grown along the [1 1 1] and [0 0 1] crystallographic directions are obtained from first principles calculations in the framework of density functional theory. It is shown that reconstructions occurring in 3C-SiC/zb-GaN by the Si and C atoms in the abrupt C-Ga, Si-Ga and Si-N, C-N interfaces, respectively, induce charge compensation and stabilize these interfaces. On the contrary, a mutual exchange of these two compensating atoms destroys the energetical stability of the discussed interfaces. Reconstruction of the C-N interface type, common for 3C-SiC/zb-GaN and diamond/c-BN by C atom, is energetically favourable in both heterostructures and it is accompanied by a similar charge transfer in [1 1 1], while the reconstruction of the analogous C-Ga and C-B interfaces is unfavourable in both cases. Finally, it is demonstrated that in the diamond/c-BN junctions grown along the [0 0 1] crystallographic direction, the most stable interfaces are of the C-N type with reconstruction in the uppermost substrate carbon layer.
