采用背向散射偏振配置,对半极性a面(1120)生长的4H-SiC晶体,测量了激发光偏振方向与光轴成不同角度时各声子振动的偏振拉曼散射光谱,研究了不同声子模式的偏振拉曼散射光的强度变化与性质。利用拉曼选择定则,对实验结果进行拟合分析得到了不同声子模式的拉曼散射矩阵张量元系数及其各向异性特征。研究结果为深入了解4H-SiC晶体的微观结构和各向异性性质提供依据。

Using the backscattering polarization configuration,the angle variations of the Raman scattered intensities of allowed phonon modes were measured for the 4H-SiC thin film grown on the semipolar a-plane (1120) and the intensity properties were investigated.According to the Raman selection rules,the Raman tensor elements of allowed phonon modes have been extracted by data fitting and the anisotropic characteristics of 4H-SiC were explored.The results provide a further understanding of the microstructure and anisotropy of 4H-SiC crystal.