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We report a novel approach for metal organic vapor phase epitaxy of (Al)GaN heterostructures on Si substrates. An approximately 90-100 nm thick SiC buffer layer is synthesized using the reaction between Si substrate and CO gas. High-resolution transmission electron microscopy reveals sharp crystalline interfaces with epitaxial relationship between SiC/Si and AlN/SiC layers. Optimization of SiC morphology and AlN seed layer thickness facilitates the growth of GaN layers free of pits (v-defects). It is also found that Si doping eliminates these defects in the case of growth on SiC templates with non-optimized surface morphology. Thus, synthesis of thin SiC buffer layer is suggested as a solution for the interface problems at the initial stage of III-N on Si epitaxy. [ABSTRACT FROM AUTHOR]

The aim of this work is to demonstrate the fundamental possibility of Si-doped GaN nanowires growth on the buffer layer of silicon carbide on silicon substrate and to investigate the optical characteristics of this structures. [ABSTRACT FROM AUTHOR]

Monolithic color synthesis is demonstrated using InGaN/GaN multiple quantum wells (QWs) grown on GaN microstripes formed by selective area epitaxy on SiO2 mask patterns. The striped microfacet structure is composed of (0001) and {11-22} planes, attributed to favorable surface polarity and surface energy. InGaN/GaN QWs on different microfacets contain spatially inhomogeneous compositions owing to the diffusion of adatoms among the facets. This unique property allows the microfacet QWs to emit blue light from the {11-22} plane and yellow light from the top (0001) plane, the mixing of which leads to the perception of white light emission. [ABSTRACT FROM AUTHOR]

In this paper, a MOCVD-GaN/Al2O3 (MGA) template was annealed under appropriate annealing conditions and N2 flow to form a porous template. The porous template was used for growing GaN by HVPE. The GaN crystal was easily separated from the porous template with the assistance of the microporous structure. The self-separated GaN crystal grown on the porous template showed a smaller full width at half maximum (FWHM) for (002) and (102) reflections in the HRXRD measurement than that grown on the MGA template. The PL results indicate that the optical quality of the GaN crystal on the porous template was improved and the dislocation density decreased. The Raman results showed that the stress in the GaN crystal grown on the porous template is much smaller than that on the MGA template. These results show that the crystalline quality of GaN crystals was improved by using the porous template. [ABSTRACT FROM AUTHOR]

A method to obtain high quality semipolar {1013} GaN grown on m-plane sapphire is presented. This method is similar to two-step nanoepitaxial lateral overgrowth (2S-NELOG) by combining a TiN interlayer and self-assembled SiO2 nanospheres. For the 2S-NELOG semi-GaN, the root-mean-square (RMS) roughness is 1.8 nm with a scan area of 5 x 5 μm². The reduction of the defect density is demonstrated using high resolution X-ray diffraction (HRXRD) and transmission electron microscopy (TEM). The full widths at half maximum (FWHMs) of the on-axis X-ray rocking curves (XRCs) are 381 and 524 arcsec, respectively rocking toward the [3032] direction and the [1210] direction. The anisotropy of the mosaic is lower compared to planar and TiN semi-GaN. In addition, Raman analyses also show the partial relaxation of the stress in the 2S-NELOG semi-GaN. [ABSTRACT FROM AUTHOR]

A new approach is proposed to the synthesis of a semipolar GaN on a Si(100) substrate at the surface of which the V‐shaped nanostructures with the characteristic size of elements as low as 100 nm are formed. It has been demonstrated that application of buffer layers of 3C‐SiC and AlN enables formation of the GaN(10–11) layer characterized by the full width at half maximum value as low as ωθ ≈45 arcmin for the X‐ray diffraction rocking curve. The model based on anisotropic nucleation of AlN on the V‐shaped nanostructure is proposed to explain the growth of the GaN layer in a single semipolar direction. In this article, Bessolov et al. focus on the growth of the GaN layer in a semipolar direction by heteroepitaxy of the GaN layer on nano‐patterned Si(100) substrate with V‐shaped nano‐grooves arranged with the period as low as 100 nm, combined with the synthesis of a nano‐sized SiC layer formed by solid‐phase substitution of silicon atoms by carbon atoms. [ABSTRACT FROM AUTHOR]