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In this paper, we address the unique nature of fully textured, high surface-to-volume 3C-SiC films, as produced by intrinsic growth anisotropy, in turn generated by the high velocity of the stacking fault growth front in two-dimensional (111) platelets. Structural interpretation of high resolution scanning electron microscopy and transmission electron microscopy data is carried out for samples grown in a hot-wall low-pressure chemical vapour deposition reactor with trichlorosilane and ethylene precursors, under suitable deposition conditions. By correlating the morphology and the X-ray diffraction analysis we also point out that twinning along (111) planes is very frequent in such materials, which changes the free-platelet configuration.

In this review paper, several new approaches about the 3C‐SiC growth are been presented. In fact, despite the long research activity on 3C‐SiC, no devices with good electrical characteristics have been obtained due to the high defect density and high level of stress. To overcome these problems, two different approaches have been used in the last years. From one side, several compliance substrates have been used to try to reduce both the defects and stress, while from another side, the first bulk growth has been performed to try to improve the quality of this material with respect to the heteroepitaxial one. From all these studies, a new understanding of the material defects has been obtained, as well as regarding all the interactions between defects and several growth parameters. This new knowledge will be the basis to solve the main issue of the 3C‐SiC growth and reach the goal to obtain a material with low defects and low stress that would allow for realizing devices with extremely interesting characteristics.

3C-SiC is a promising material for low-voltage power electronic devices but its growth is still challenging. Heteroepitaxy of 3C-SiC on Si micrometer-sized pillars is regarded as a viable method to achieve high crystalline quality, minimizing the effects of lattice and thermal expansion mismatch. Three-dimensional micro-crystals with sharply-faceted profiles are obtained, eventually touching with each other to form a continuous layer, suspended on the underlying pillars. By comparing experimental data and simulation results obtained by a phase-field growth model, here we demonstrate that the evolution of the crystal morphology occurs in a kinetic regime, dominated by the different incorporation times on the crystal facets. These microscopic parameters, effective to characterize the out-of-equilibrium growth process, are estimated by a best-fitting procedure, matching simulation profiles to the experimental one at different deposition stages. Then, simulations are exploited to inspect the role of a different pillar geometry and template effects are recognized. Finally, coalescence of closely spaced crystals ordered into an hexagonal array is investigated. Two possible alignments of the pattern are compared and the most convenient arrangement is evaluated.

We present an investigation of the structural quality of arrays of 3C-SiC micropillars and microridges grown epitaxially on deeply etched Si(0 0 1) substrates offcut towards [1 1 0]. Using high resolution X-ray diffraction with reciprocal space mapping and optical as well as scanning electron microscopy, we obtain information about the stacking fault (SF) formation in different crystallographic directions. The SF density is strongly correlated with the microcrystal size and orientation and a reduction of the SF density is found in the [1 1 1] and [1 −1 1] directions. No variation of the average SF size was detected for varying SiC microcrystal size and shape.

In this work, the annihilation mechanism of stacking faults (SFs) in epitaxial 3C-SiC layers grown on Si(001) substrates is studied by molecular dynamics (MD) simulations. The evolution of SFs located in the crossing (1̄11) and (11̄1) glide planes is considered. This evolution is determined by the interaction of 30° leading partial dislocations (PDs) limiting the stacking faults under the slightly compressive (∼0.45%) strain condition during the 3C-SiC layer growth. It is characterized in key terms: the distance between the PDs and the mutual orientation of their Burgers vectors. Two SF annihilation scenarios are revealed. In the first scenario, two PDs with opposite screw components of Burgers vectors, leading the SFs located in the (1̄11) and (11̄1) planes, are close enough (∼15 nm or less) and attract each other. As a result, the propagation of both SFs is suppressedviathe formation of a Lomer-Cottrell lock at their intersection. In the second scenario, two PDs are far away one from the other (beyond ∼15 nm) and do not interact, or they repulse each other having equal screw components of their Burgers vectors. In this case, the propagation of only one of the SFs is suppressed. Obtained results explain the mechanism of SF annihilation and formation of SF intersection patterns experimentally observed by TEM investigations. They will provide important implications for the elaboration of advanced methods for the reduction of SF concentrations in epitaxial 3C-SiC layers on Si substrates.

The cubic polytype of SiC (3C-SiC) is the only one that can be grown on silicon substrate with the thickness required for targeted applications. However, the crystalline quality of 3C-SiC on silicon has to be improved in order to benefit from the intrinsic 3C-SiC properties. In this project new approaches for the reduction of defects will be used and new compliance substrates that can help to reduce the stress and the defect density at the same time will be explored. Numerical simulations will be applied to optimize growth conditions and reduce stress in the material. The structure of the final devices will be simulated using the appropriated numerical tools where new numerical model will be introduced to take into account the properties of the new material. Thanks to these simulations tools and the new material with low defect density, several devices that can work at high power and with low power consumption will be realized within the project.

Silicon carbide (SiC) is a compound semiconductor, which is considered as a possible alternative to silicon for particles and photons detection. Its characteristics make it very promising for the next generation of nuclear and particle physics experiments at high beam luminosity. Silicon Carbide detectors for Intense Luminosity Investigations and Applications (SiCILIA) is a project starting as a collaboration between the Italian National Institute of Nuclear Physics (INFN) and IMM-CNR, aiming at the realization of innovative detection systems based on SiC. In this paper, we discuss the main features of silicon carbide as a material and its potential application in the field of particles and photons detectors, the project structure and the strategies used for the prototype realization, and the first results concerning prototype production and their performance.

The stacking faults (SFs) in 3C-SiC epitaxially grown on ridges deeply etched into Si(001) substrates offcut towards [110] were quantitatively analyzed by electron microscopy and X-ray diffraction. A significant reduction of SF density with respect to planar material was observed for the {111} planes parallel to the ridges. The highest SF density was found in the (-1-11) plane. A previously observed defect was identified as twins by electron backscatter diffraction.

The growth morphology of epitaxial 3C-SiC crystals grown on hexagonal pillars deeply etched into Si(111) substrates is presented. Different growth velocities of side facets let the top crystal facet evolve from hexagonal towards triangular shape during growth. The lateral size and separation between Si pillars determine the onset of fusion between neighboring crystals during growth at a height tailoring of which is crucial to reduce the stacking fault (SF) density of the coalesced surface. A density of 3400 cm-1 was observed for a coalesced surface, compared to 8100 cm-1 for layers grown on unpatterned area. Intermediate partial fusion of neighboring crystals is shown as well as a surface of fully coalesced crystals.

We have developed a transfer process of 3C-SiC-on-Si (100) seeding layers grown by chemical vapor deposition onto a poly-or single-crystalline SiC carrier. Applying subsequent sublimation growth of SiC in [100] direction resulting in large area crystals (up to approximate to 11 cm(2)) with a thickness of up to approximately 850 lm. Raman spectroscopy, Laue X-ray diffraction and electron-backscattering-diffraction revealed a high material quality in terms of single-crystallinity without secondary polytype inclusions, antiphase boundaries or double positioning grain boundaries. Defects in the bulk grown 3C-SiC, like protrusions with surrounding stressed areas, stem from the epitaxial seeding layer. The presented concept using 3C-SiC-on-Si seeding layers reveals a path for the growth of bulk 3C-SiC crystals. (C) 2017 Elsevier B.V. All rights reserved., Funding Agencies|STAEDLER Foundation [WW/eh13/15]; European commission (CHALLENGE project) [720827]

The heteroepitaxial growth of 3C-SiC on Si(001) and Si(111) substrates deeply patterned at a micrometer scale by low-pressure chemical vapor deposition is shown to lead to space-filling isolated structures resulting from a mechanism of self-limitation of lateral expansion. Stacking fault densities and wafer bowing may be drastically reduced for optimized pattern geometries.

We show that geometric shielding of the reactive flux in chemical vapor deposition by tall neighboring structures obtained by deep substrate patterning, along with short surface diffusion lengths, can provide nearly space filling arrays of high-quality epitaxial crystals despite large mismatches of lattice parameters and thermal expansion coefficients. The density of extended defects is strongly reduced by the method, and wafer bowing and crack formation largely inhibited. The concept is shown to be valid for SiGe/Si heterostructures ranging from pure Si to pure Ge both on Si(001) and Si(111) substrates. Here, dislocations are efficiently eliminated from three-dimensional faceted crystals with high-aspect ratios on top of micron-sized Si pillars. The application to 3C-SiC/Si(001) ridges, characterized by a lattice mismatch of nearly 20%, provides significantly lower stacking fault densities compared with layers grown on planar substrates