Crystalline SiC samples were prepared in solidification of silicon melt saturated by carbon solved from the inner wall of a graphite crucible.The Crystalline structure of the samples was analysed in Raman spectroscopy...Crystalline SiC samples were prepared in solidification of silicon melt saturated by carbon solved from the inner wall of a graphite crucible.The Crystalline structure of the samples was analysed in Raman spectroscopy and confirmed as 3C-SiC both in x-ray diffraction and x-ray photoelectron spectroscopy(XPS).The Raman spectra of the samples present a strong sharp peak located at 796.3 cm^(-1) with a full width at half maximum about 6 cm^(-1) and three weak peaks broadened around 1525.6,1631.4 and 1719.1 cm^(-1),respectively.The former belongs to the transverse optical phonons of 3C-SiC,while the latter can be attributed to the second-order scattering.However,the longitudinal optical mode of 3C-SiC has not been found for our samples.An additional broadened peak at 532.2 cm^(-1) may imply the existence of some lattice defect in the samples,which is related to nitrogen introduced unintentionally into the lattice in the growth process and confirmed in XPS of N 1s binding energy centered at 400.9 eV.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.69876030.
文摘Crystalline SiC samples were prepared in solidification of silicon melt saturated by carbon solved from the inner wall of a graphite crucible.The Crystalline structure of the samples was analysed in Raman spectroscopy and confirmed as 3C-SiC both in x-ray diffraction and x-ray photoelectron spectroscopy(XPS).The Raman spectra of the samples present a strong sharp peak located at 796.3 cm^(-1) with a full width at half maximum about 6 cm^(-1) and three weak peaks broadened around 1525.6,1631.4 and 1719.1 cm^(-1),respectively.The former belongs to the transverse optical phonons of 3C-SiC,while the latter can be attributed to the second-order scattering.However,the longitudinal optical mode of 3C-SiC has not been found for our samples.An additional broadened peak at 532.2 cm^(-1) may imply the existence of some lattice defect in the samples,which is related to nitrogen introduced unintentionally into the lattice in the growth process and confirmed in XPS of N 1s binding energy centered at 400.9 eV.
