Photoluminescence properties of N and B codoped fluorescent 4H-SiC and 6H-SiC single crystals

Abstract

In this paper, N and B codoped 4H-SiC and 6H-SiC single crystals were prepared by physical vapour transport method and their photoluminescence properties were studied. The photoluminescence spectra, dopant concentrations, Raman spectra, and transmission spectra of these obtained crystals were characterized. It is observed that the fluorescent crystals radiate a warm white light that covers a wide band spectrum from 450 nm to 750 nm when they are excited by a 325 nm laser. The doped 4H-SiC single crystal presents a higher photoluminescence intensity and larger spectral band compared to that of doped 6H-SiC single crystal under the similar growth and measurement conditions. Further analyze by doping concentration and transmission spectra indicate that the photoluminescence property is strongly influenced by the N donor and B acceptor impurity level.

White light emission of wide‐bandgap silicon carbide: A review

“…Scientists have also developed f-SiC via PVT method. 50,52,53,67 The growth of the fluorescent 4H-SiC single crystal by PVT process has been reported by Liu et al 52 In this process, 3-inch diameter and 300-μm thick 4H-SiC crystals are grown in the temperature range of 2040 under 325 nm laser source at room temperature and 4 K, as shown in Figure 9. From the PL measurements of the two samples at room temperature, as shown in Figure 9A, wide emission spectra from 450 to 750 nm centered at 528 nm have been observed for SA-4H, but in the case of SA-6H, narrower spectra (520-750 nm) with peak wavelength at 590 nm have been obtained.…”

“…Scientists have also developed f‐SiC via PVT method 50,52,53,67 . The growth of the fluorescent 4H‐SiC single crystal by PVT process has been reported by Liu et al 52 .…”

“…Fabrication mechanism of N–B co‐doped 4H‐SiC and 6H‐SiC single crystals via PVT method has been explained in the research work of Zhou et al 53 . The growth process is performed in the temperature range of 2030°C–2100°C in the mixed atmosphere of Ar and N 2 , with high‐purity B 4 C and SiC powders.…”

“…Liu et al 52 developed N-B-Al co-doped fluorescent 4H-SiC crystals by PVT method and studied DAP emission in different temperature parameters. Fabrication of 4H-SiC and 6H-SiC single crystals by PVT route and white light emission from these fluorescent crystals in the range of 450-750 nm have been reported in the experimental work of Zhuo et al 53 Optical properties such as carrier lifetime and quantum efficiency of largely used SiC polytypes are summarized in Table 3.…”

Influence of microwave radiation on relaxation processes in silicon carbide

“…The band in the range near 460 nm in the PL spectra of silicon carbide is associated with the presence of luminescence centers caused by intrinsic defects [9] or by violation of the stoichiometry of silicon carbide crystals [10], as it is mentioned in the literature. The authors of [11][12][13] correlate the PL bands within the range 400…600 nm with recombination of donor-acceptor pairs of the type i-centernitrogen or admixture (nitrogen)defect.…”