25 research outputs found
HRXRD study of the effect of a nanoporous silicon layer on the epitaxial growth quality of GaN layer on the templates of SiC/por-Si/c-Si
Using High Resolution X-ray Diffraction (HRXRD) diagnostic techniques the influence of the transition layer of nanoporous silicon on the practical implementation and certain features of the epitaxial growth of GaN layers with the use of molecular beam epitaxy were investigated by means of plasma activation of nitrogen (MBE PA) on the templates of SiC/por-Si/c-Si. For the first time it was shown that introducing of the transition layer of nanoporous silicon in the template of SiC/por-Si/c-Si where the layer of 3C-SiC was obtained by substitution of the atoms had a number of indisputable advantages as compared with conventional silicon substrates. Particularly, such an approach, in fact, enabled a 90% reduction in the level of stresses in the crystalline lattice of the epitaxial GaN layer which was synthesized on SiC surface of SiC/por-Si/c-Si template by means of MBE PA technique as well as to decrease some of vertical dislocations within GaN layer. © 2020 The AuthorsRussian Science Foundation, RSFThe work was executed under support of the grant of Russian Science Foundation 19-72-10007 . Access to KNMF equipment was obtained under the grant of the President of the Russian Federation MD-42.2019.2
Study of semi-polar gallium nitride grown on m-sapphire by chloride vapor-phase epitaxy
In this study, we analyzed the result of the influence of the non-polar plane of a sapphire substrate on the structural, morphological, and optical properties and Raman scattering of the grown epitaxial GaN film.
It was found that selected technological conditions for the performed chloride-hydride epitaxy let us obtain the samples of structurally qualitative semi-polar wurtzite gallium nitride with (11¯22) orientation on m-sapphire. Using a set of structural and spectral methods of analysis the structural, morphological, and optical properties of the films were studied and the value of residual bi-axial stresses was determined. A complex of the obtained results means a high structural and optical quality of the epitaxial gallium nitride film.
Optimization of the applied technological technique in the future can be a promising approach for the growth of the qualitative GaN structures on m-sapphire substrates
Selective area epitaxy of n+-GaN layers on SiO2 patterned GaN/c-Al2O3 templates by PA MBE
The n+-GaN epilayers were synthesised by PA MBE on the SiO2 patterned GaN/c-Al2O3 templates, grown by MOCVD. Formation of the polycrystalline GaN atop of the SiO2 mask during PA MBE was observed. It was found that macroscopic voids at the interface polycrystalline GaN/SiO2/n-GaN template appeared during the PA MBE process. The polycrystalline GaN film was completely removed by etching in hot aqueous KOH solution. Hall measurements have shown that the value of electron concentration in n+-GaN contact layer is about ne∼4.6×1019 cm-3.Peer reviewe