In Situ Doping of Nitrogen in <110>-Oriented Bulk 3C-SiC by Halide Laser Chemical Vapour Deposition

Abstract

Doping of nitrogen is a promising approach to improve the electrical conductivity of 3C-SiC and allow its application in various fields. N-doped, &lt;110&gt;-oriented 3C-SiC bulks with different doping concentrations were prepared via halide laser chemical vapour deposition (HLCVD) using tetrachlorosilane (SiCl4) and methane (CH4) as precursors, along with nitrogen (N2) as a dopant. We investigated the effect of the volume fraction of nitrogen (ϕN2) on the preferred orientation, microstructure, electrical conductivity (σ), deposition rate (Rdep), and optical transmittance. The preference of 3C-SiC for the &lt;110&gt; orientation increased with increasing ϕN2. The σ value of the N-doped 3C-SiC bulk substrates first increased and then decreased with increasing ϕN2, reaching a maximum value of 7.4 × 102 S/m at ϕN2 = 20%. Rdep showed its highest value (3000 μm/h) for the undoped sample and decreased with increasing ϕN2, reaching 1437 μm/h at ϕN2 = 30%. The transmittance of the N-doped 3C-SiC bulks decreased with ϕN2 and showed a declining trend at wavelengths longer than 1000 nm. Compared with the previously prepared &lt;111&gt;-oriented N-doped 3C-SiC, the high-speed preparation of &lt;110&gt;-oriented N-doped 3C-SiC bulks further broadens its application field.

The effect of nitrogen doping and heat treatment on electrical resistivity of CVD SiC bulks

“…The specimens with N 2 flow rate of 0.2 and 20 l min −1 exhibit prototypical fine crystal morphologies, as evidenced in figure 2(a), while figure 2(b) portrays a pyramid-like structure. Interestingly, compared to the previous study [21], doping with increased nitrogen concentration usually induces the development of pyramid morphology, but the observation results in this article are different. The experimental CVD reactor employed in this investigation features an expansive cavity and suboptimal flow field stability.…”

Investigation of Al droplet wetting behavior on highly-oriented SiC

“…For 3C-SiC, only 〈111〉 and 〈110〉 are common orientations. Therefore, this study uses the Lotgering orientation factor to calculate the selective orientation of 3C-SiC as follows: 24 F hkl = ( P hkl − P 0 )/(1 − P 0 ) where P hkl and P 0 are the ratios of the XRD peak intensities of the SiC coating ( hkl ) and SiC powder ( hkl ) crystalline surface to the sum of the XRD peak intensities of all crystalline surfaces, respectively. In the range of 2 θ = 10–90°, the (111) and (222) crystal planes belong to the same 〈111〉 orientation, so it is necessary to superimpose the diffraction intensity of the (111) and (222) crystal planes in the calculation of F 111 .…”