We introduce a 3C-SiC growth concept on off-oriented 4H-SiC substrates using a sublimation epitaxial method. A growth model of 3C-SiC layer development via a controlled cubic polytype nucleation on in situ formed on-axis area followed by a lateral enlargement of 3C-SiC domains along the step-flow direction is outlined. Growth process stability and reproducibility of high crystalline quality material are demonstrated in a series of 3C-SiC samples with a thickness of about 1 mm. The average values of full width at half-maximum of ω rocking curves on these samples vary from 34 to 48 arcsec indicating high crystalline quality compared to values found in the literature. The low temperature photoluminescence measurements also confirm a high crystalline quality of 3C-SiC and indicate that the residual nitrogen concentration is about 1-2×10 16 cm -3 . Such 3C-SiC growth concept may be applied to produce substrates for homoepitaxial 3C-SiC growth or seeds which could be explored in bulk growth of 3C-SiC.

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We investigated the formation of structural defects in thick (~ 1mm) 3C-SiC layers grown on off-oriented 4H-SiC substrates via lateral enlargement mechanism using different growth conditions. A two-step growth process based on this technique was developed, which provides a trade-off between the growth rate and the number of defects in the 3C-SiC layers. Moreover, we demonstrated that the twostep growth process combined with geometrically controlled lateral enlargement mechanism allows formation of single 3C-SiC domain which enlarges and completely covers the substrate surface. High crystalline quality of the grown 3C-SiC layers is confirmed using high resolution x-ray diffraction and low temperature photoluminescence measurements. ABSTRACTWe investigated the formation of structural defects in thick (~ 1mm) 3C-SiC layers grown on off-oriented 4H-SiC substrates via lateral enlargement mechanism using different growth conditions. A two-step growth process based on this technique was developed, which provides a trade-off between the growth rate and the number of defects in the 3C-SiC layers. Moreover, we 3 demonstrated that the two-step growth process combined with geometrically controlled lateral enlargement mechanism allows formation of single 3C-SiC domain which enlarges and completely covers the substrate surface. High crystalline quality of the grown 3C-SiC layers is confirmed using high resolution x-ray diffraction and low temperature photoluminescence measurements.

Abstract. In order to analyze the epitaxial growth of cubic silicon carbide by sublimation epitaxy on different substrates, four different 6H-SiC substrates preparations were used: (i) as-received, (ii) repolished, (iii) annealed and covered by silicon layer, (iv) with (111) 3C-SiC buffer layer. Almost 100% coverage and low twin density was achieved when growing on the buffer layer. The XRD and TEM characterizations show better material quality when layer is grown directly on 6H-SiC substrates.Background doping evaluated by LTPL is in the range of 10 16 cm -3 for N and 10 15 cm -3 for Al in all grown layers.

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Abstract:Cubic silicon carbide is a promising material for medium power electronics operating at high frequencies and for the subsequent growth of gallium nitride for more efficient light emitting diodes. We present a new approach to produce freestanding cubic silicon carbide (3C-SiC) with the ability to obtain good crystalline quality regarding increased domain size and reduced defect density. This would pave the way to achieve substrates of 3C-SiC so that the applications of cubic silicon carbide material having selectively (111) or (001) oriented surfaces can be explored. Our method is based on the combination of the chemical vapor deposition method and the fast sublimation growth process. Thin layers of cubic silicon carbide grown heteroepitaxially on silicon substrates are for the first time used for a subsequent sublimation growth step to increase layer thicknesses. We have been able to realize growth of freestanding (001) oriented 3C-SiC substrates using growth rates around 120 µm/h and diameters of more than ten millimeters. The structural quality from XRD rocking curve measurements of (001) oriented layers shows good FWHM values down to 78 arcsec measured over an area of 1x2 mm 2 , which is a quality improvement of 2-3 times compared with other methods like CVD.

As a challenge and consequence due to its metastable nature, cubic silicon carbide (3C-SiC) has only shown inferior material quality compared with the established hexagonal polytypes. We report on growth of 3C-SiC(111) having a state of the art semiconductor quality in the SiC polytype family. The x-ray diffraction and low temperature photoluminescence measurements show that the cubic structure can indeed reach a very high crystal quality. As an ultimate device property, this material demonstrates a measured carrier lifetime of 8.2 mu s which is comparable with the best carrier lifetime in 4 H-SiC layers. In a 760-mu m thick layer, we show that the interface recombination can be neglected since almost all excess carriers recombines before reaching the interface while the surface recombination significantly reduces the carrier lifetime. In fact, a comparison of experimental lifetimes with numerical simulations indicates that the real bulk lifetime in such high quality 3C-SiC is in the range of 10-15 mu s

Abstract. Growth of 3C or 6H-SiC epilayers on low off-axis 6H-SiC substrates can be mastered by changing the size of the on axis plane formed by long terraces in the epilayer using geometrical control. The desired polytype can be selected in thick (~200 µm) layers of both 6H-SiC and 3C-SiC polytypes on substrates with off-orientation as low as 1.4 and 2 degrees. The resultant crystal quality of the 3C and the 6H-SiC epilayers, grown under the same process parameters, deteriorates when lowering the off-orientation of the substrate.