The morphology of ALN layers grown by Metalorganic Chemical Vapor Deposition on nano-structured NP-Si(001) substrates coated with SiNx has been studied using atomic force microscopy. The AlN layers grown on the SiNx/NP-Si(100) template demonstrate a surface roughness 3.8 times less than those obtained on NP-Si(100), and are close to the roughness value for the AlN layer grown on a flat Si(111) substrate. It has been proposed a model to explain the differences in the formation of the surface morphology of AlN layers on the NP-Si(100) substrate and the SiNx/NP-Si(100) template.

The experimental results of the recent years on the synthesis of semipolar wide-band III–N-layers on a nanostructured silicon substrate are summarized. The idea of synthesis involves the formation of Si(111) side walls on the silicon surface, then the epitaxial nucleation of the layer in the “c” direction of the crystal, followed by the fusion of blocks in the semipolar direction of the surface. Examples of orientation controlling epitaxy of semipolar AlN(10–11)-, GaN(10–11)-, GaN(11–22)-layers synthesized on nanostructured Si(100), Si(113) substrates by methods of metalorganic vapor phase epitaxy and hydride vapor phase epitaxy are shown. The review presents a summary and the prospects for further developments in the field of optoelectronics based on the platform—“semipolar GaN on Si.”

It has been studied the morphology of the surface of the semipolar gallium nitride layers synthesized on nano-pattemed Si(100) or Si(113) substrates with a V-shaped or U-shaped surface profile, respectively. The morphology of the surface of the semipolar layers indicates that the different height-to-width ratio of the GaN(11-22) and GaN(10-11) blocks is associated with a higher growth rate of the GAN(11-22) face than GaN(10-11) and with different growth rates of the semipolar and polar crystal faces during the nucleation of the layer on a nano-patterned substrate.

scanning electron microscopy was used to study of the initial stages of the formation of a semipolar GaN(11 2̅ 2) layer during Metalorganic Chemical Vapor Deposition on Si(113) substrates, on the surface of which U-shaped grooves with element sizes <100 nm (NP-Si(113)) were formed. It was found that NP-Si(113) substrates with a buffer AlN layer stimulate the formation of islands faceted by the planes m-GaN, c‑GaN. It is shown that there is a predominant growth of the m-GaN facet in comparison with c-GaN. The experimental results correspond to the Gibbs-Curie-Wolff selection principle, but taking into account elastic stresses in the c-GaN plane.

The article reports the growth of semi-polar GaN(11-22) layers using epitaxy from metal organic compounds on a nanostructured NP-Si(113) substrate. It was shown that upon the emergence of an island layer, elastic deformed structures of GaN(11-22)/NP-Si(113) form a nano-meter compliant silicon layer on a substrate while elastic stresses conditioned by the difference of temperature coefficients of GaN and Si in such a structure decrease

Scanning electron microscopy was used to study of the initial stages of the formation of a semipolar GaN(1122) layer during Metalorganic Chemical Vapor Deposition on Si(113) substrates, on the surface of which U-shaped grooves with element sizes <100 nm (NP-Si(113)) were formed. It was found that NP-Si(113) substrates with a buffer AlN layer stimulate the formation of islands faceted by the planes m-GaN, c-GaN. It is shown that there is a predominant growth of the m-GaN facet in comparison with c-GaN.The experimental results correspond to the Gibbs--Curie--Wolff selection principle, but taking into account elastic stresses in the c-GaN plane. Keywords: semipolar gallium nitride, nano-structured substrate, silicon.

scanning electron microscopy was used to study of the initial stages of the formation of a semipolar GaN(1122) layer during Metalorganic Chemical Vapor Deposition on Si(113) substrates, on the surface of which U-shaped grooves with element sizes <100 nm (NP-Si(113)) were formed. It was found that NP-Si(113) substrates with a buffer AlN layer stimulate the formation of islands faceted by the planes m-GaN,c-GaN. It is shown that there is a predominant growth of the m-GaN facet in comparison with c-GaN. The experimental results correspond to the Gibbs-Curie-Wolff selection principle, but taking into account elastic stresses in the c-GaN plane.

Методом растровой электронной микроскопии изучались начальные стадии формирования полуполярного GaN(1122) слоя при эпитаксии из металлоорганических соединений на подложках Si(113), на поверхности которых сформированы U-образные канавки с размером элементов <100 нм (подложка-NP-Si(113)). Установлено, что NP-Si(113) подложки с буферным слоем AlN стимулируют формирование островков, ограненных плоскостями m-GaN, c-GaN. Показано, что наблюдается преимущественный рост грани m-GaN по сравнению с c-GaN. Экспериментальные результаты соответствуют принципу отбора Гиббса--Кюри--Вульфа, но с учетом упругих напряжений в плоскости c-GaN. Ключевые слова: полуполярный нитрид галлия, нано-структурированная подложка, кремний.

A method for synthesising hexagonal GaN on a Si(113) substrate with a nanostructure of about 75 nm on its surface ( NP-Si(113) substrate) is proposed. It has been established that the method of the metal-organic chemical vapor deposition on such a substrate makes it possible to form a semi-polar layer of GaN(11-22) with half-widths of the X-ray diffraction curve omega(theta) similar to 30 arcmin. It is shown that during epitaxy from organometallic compounds in hydrogen atmosphere at the initial stages of growth the layer orientation is given by the direction of Si(111) plane of nanocanals in NP-Si(113) and the growth rate of GaN layer in (11-22) and (0001) planes direction is comparable.

The experimental results of the recent years on the synthesis of semipolar wide-band III-N layers on a nanostructured silicon substrate are summarized. The idea of synthesis involves the formation of Si(111) side walls on the silicon surface, then the epitaxial nucleation of the layer in the “c” direction of the crystal, followed by the fusion of blocks in the semipolar direction of the surface. Examples of orientation controlling epitaxy of semipolar AlN(10-11), GaN(10-11), GaN(11-22) layers synthesized on nanostructured Si(100), Si(113) substrates by methods of metalorganic vapor phase epitaxy and hydride vapor phase epitaxy are shown. The review presents a summary and the prospects for further developments in the field of optoelectronics based on the platform - semipolar GaN on Si.

Results from studying deformation are obtained for semipolar GaN(11–22) grown on a nanostructured Si(113) substrate and polar GaN(0001) grown on a flat Si(111) substrate. A comparison of the structures of semipolar and polar epitaxy reveals a drop in layer deformation resulting from the smaller difference between the coefficients of thermal expansion of the substrate and gallium nitride in the semipolar direction of the crystal than in the polar direction.

We report on the fabrication of nonpolar GaN(11‒20) structures by hydride vapor phase epitaxy using an AlN buffer layer synthesized by metalorganic vapor-phase epitaxy on an r-Al2O3 substrate. It is shown that the elastic stresses in the GaN(11‒20)/r-Al2O3 structure in the directions of the c and a axes of the layer have different values, correlate with the full widths at half maximum of the rocking curves in the X-ray diffraction spectra in these directions, and are caused by the anisotropy of the thermal expansion coefficients of the layer and substrate lattices.

This paper proposes a method for synthesis of hexagonal GaN on Si(100) and Si(113) substrates, where nanostructures with an element size less than 100 nm are formed on the surface. It has been established that the method of gas-phase epitaxy from metalorganic compounds in a hydrogen atmosphere on such substrates makes it possible to form semipolar layers of GaN(10-11) and GaN(11-22) with a minimum half-width of the X-ray diffraction swing curve of about 30 arcmin. It is shown that during the formation of a semipolar AlN layer at the initial stage of epitaxy, a corrugated surface is formed on NP-Si(100) from the semipolar planes AlN(10-11) and AlN(10-1-1) with counter-directional c axes. Then, during the growth of the GaN layer, a transition is made from the symmetrical state of the semipolar GaN(10-11) and GaN(10-1-1) planes to an asymmetric state with the orientation of the c axis of the GaN(10-11) layer. That transition is apparently determined by the difference in the values of the surface energy of GaN during epitaxy on the corrugated surface.

It has been studied the morphology of the surface of the semipolar gallium nitride layers synthesized on nano-structured Si(100) or Si(113) substrates with a V-shaped or U–shaped surface profile, respectively. The morphology of the surface of the semipolar layers indicates that the different height-to-width ratio of the GaN(11-22) and GaN(10-11) blocks is associated with a higher growth rate of the GAN(11-22) face than GaN(10-11) and with different growth rates of the semipolar and polar crystal faces during the nucleation of the layer on a nano-structured substrate.

The epitaxial growth of AlN and GaN layers is investigated using metalorganic vapor-phase epitaxy on a Si(100) substrate, on the surface of which a V-shaped nanostructure with elements of sub-100-nm size (NP-Si(100) substrate) is formed. It is shown that a corrugated surface is formed from semipolar AlN(10 $$\bar {1}$$ 1) planes with opposite axes of symmetry c during the formation of a semipolar AlN layer at the initial stage of epitaxy. Then, during the growth of the GaN layer, the transition from the symmetric state of two semipolar AlN planes to an asymmetric state with a single orientation of the c axis of the semipolar GaN(10 $$\bar {1}$$ 1) layer occurs, and the c direction in the growing semipolar layer coincides with the direction of the flow of $${\text{N}}_{2}^{ + }$$ ions to the silicon surface during the formation of a nanomask.

Scanning electron microscopy is used for studies of the initial stages of the formation of semipolar AlN (10 $$\bar {1}$$ 1) and AlN (10 $$\bar {1}$$ 2) layers during metal–organic vapor-phase epitaxy on a Si (100) substrate with a surface, on which a V-shaped nanostructure, whose elements are <100 nm in dimensions, is formed (a NP-Si(100) substrate). It is shown that, in the initial stage of epitaxy on the NP-Si(100) substrate, nuclei of AlN crystals are formed and then, depending on the crystallographic orientation of the V walls, crystals faceted by AlN (10 $$\bar {1}$$ 1) or AlN (10 $$\bar {1}$$ 2) planes are formed, correspondingly, on Si (111) or Si (111) misoriented in the [110] direction by 7°.

A study is performed of the advantages of synthesizing layers of AlN via gas-phase chloride epitaxy and layers of GaN via organometallic epitaxy on a nanostructured Si(100) substrate. It is shown that when AlN(10–11) and GaN(10–11) block layers have half-widths of the X-ray diffraction swing curve equal to 60 and 45 arcmin, respectively, the surfaces of the layers have steps whose heights are determined by the size of the block upon coalescence.

Сообщается о росте неполярных GaN(1120) структур методом хлорид-гидридной газофазной эпитаксии с использованием буферного слоя AlN, синтезированного методом эпитаксии из металлоорганических соединений на подложке r-Al2O3. Показано, что упругие напряжения в структуре GaN(1120)/r-Al2O3 в направлении осей "c" и "a" слоя различаются, коррелируют с величинами полуширин кривых качания спектров рентгеновской дифракции в этих направлениях и обусловлены анизотропией коэффициентов термического расширения решеток как слоя, так и подложки. Ключевые слова: неполярный нитрид алюминия, анизотропия напряжений в слое.

It has been reported the growth of nonpolar GaN(11 ̄20) structures by hydride vapor phase epitaxy, which used an AlN buffer layer synthesized by epitaxy from organometallic compounds on an r-Al2O3 substrate. It has been shown that the elastic stresses in the GaN(11 ̄20)/r-Al2O3 structure in the direction of the ”c“and ”a“axes of the layer differ, correlate with the values of the full width at half maximum of the X-ray diffraction spectra in these directions and are due to the anisotropy of the thermal expansion coefficients of the lattice, both the layer and the substrate.

Методом растровой электронной микроскопии изучались начальные стадии формирования полуполярных AlN(1011) и AlN(1012) слоев при эпитаксии из металлоорганических соединений на подложке Si(100), на поверхности которой сформирована V-образная наноструктура с размером элементов <100 нм (подложка-NP-Si(100)). Показано, что на начальной стадии эпитаксии на подложке-NP-Si(100) происходит формирование зародышевых кристаллов AlN, а затем в зависимости от кристаллографической ориентации V-стенок формируются кристаллы, ограненные плоскостями AlN(1011) на Si(111) или AlN(1012) на Si(111), разориентированном в направлении [110] на 7o. Ключевые слова: полуполярный нитрид алюминия, наноструктурированная подложка кремния.