4H silicon carbide substrates of good crystallographic perfection and off-cut of 8^o, 4^o and 0^o were systematically investigated with conventional and synchrotron X-ray diffraction topography and X-ray reflectometry before and after the epitaxial deposition performed at 1560^oC with CVD method. The samples were grown with three different growth rates 2, 6 and 12 mm/min and the middle of these values was chosen to be most widely used in other technological manufacturing of SiC layers. The layers were not intentionally doped, while the concentration of substitutional aluminum atoms in the n type substrates was at the level of 10¹⁸ cm^-3.

The defect structure was carefully studied before and after the epiataxial layer growth with a number of X-ray methods including white beam and monochromatic beam topography. The white beam topographic investigations were performed both in transmission and back-reflection geometry. In order to examine the dislocations in larger area we applied the conventional transmission Lang topography using Mo Ka₁ radiation. The topographic methods enabled the identification of the most of defects present in the sample using both the extinction analysis and the simulation of the diffraction images.

The topographic investigations performed after the deposition of the epitaxial layers in the samples with  8^o and 4^o off-cut confirmed the continuation of the dislocations in the epitaxial deposit. We did not observe any formation of new dislocations and any other extended defects in the epitaxial all three growth rates.

Contrary to that we found a distinct difference of the surface roughness of the layers deposited at different growth rates: the difference is found to increase with increasing applied growth rate.

The presently applied conditions were not suitable to obtain the single polytype 4H-SiC epitaxial deposit for the substrates with 0^o off-cut, and the obtained layer contained a large amount of differently distributed other polytypes, especially the 3C one. An interesting phenomenon was observed in the case of the layer deposited at 12 mm/min growth rate, when the 3C polytype formed islands of relatively large dimensions reaching single  hundreds of microns or even single millimeters. These islands  contained several misfit dislocations and other new created defects.

Acknowledgements: The present work was supported by the grant of Ministry of Science and High Education, N N N 505 379737 while the synchrotron investigations were supported by the EC 20100001 HASYLAB project.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/24586 must be provided.

1. The influence of pressure on growth of 3C-SiC heteroepitaxial layers on silicon substrates
2. CVD of graphene on SiC
3. New Ca₁₀Li(VO₄)₇ laser host: growth and properties
4. Pinned and unpinned epitaxial and sublimated graphene on SiC
5. Characterization of the defect structure in gadolinium orthovanadate single crystals grown by the Czochralski method
6. Synchrotron topographic studies of domain structure in Czochralski grown Pr_xLa_1-xAlO₃ crystals
7. Evaluation of the depth extension of the damages induced by FLASH pulses in silicon crystals
8. Damage of gallium arsenide created after irradiation by ultra-short VUV laser pulse
9. Synthesis of gallium nitride nanowires by Sublimation Sandwich Method
10. Raman spectroscopy of single and multilayer graphene on SiC substrates
11. Growth of GaN layers on silicon and sintered GaN nano-ceramic substrates – TEM investigations
12. Observation of individual dislocations in 6h and 4h sic by means of back-reflection methods of x-ray diffraction topography
13. Synchrotron topographic investigation of SiC bulk crystals and epitaxial layers
14. The investigation of structural perfection and facetting in highly Er - doped Yb₃Al₅O₁₂ crystals
15. Observation of defects in g - irradiated Cz-si annealed under high pressure
16. Growth of high resistivity GaN layers by compensating defects generation
17. X-ray topography of Ca_0.5Sr_0.5NdAlO₄ single crystal
18. MOCVD growth and characterization of ultrathin AlN/GaN superlattices on 0001 sapphire substrates
19. Investigation of insulated buried layers obtained by ion implantation in AlGaAs with various Al concentration
20. Electrical Properties of GaN/AlGaN Hetrostructures
21. GaN growth by Sublimation Sandwich Method
22. Mg diffusion in GaN:Mg grown by metalorganic vapor-phase epitaxy MOVPE
23. Optical investigations of two dimensional electron gas in the AlGaN/GaN heterostructures
24. Problems with cracking of Al_xGa_1-xN layers
25. Synchrotron X-ray Diffraction studies of silicon implanted with high energy Ar ions after thermal annealing
26. Crystal structure and thermal expansion of PrGaO₃ in the temperature range 10-1253 K