Center for Microscopy-Microanalysis and Information Processing, University Politehnica of Bucharest, 313 Splaiul Independentei, 060042 Bucharest, Romania.
Sci Rep. 2014 Jun 11;4:5258. doi: 10.1038/srep05258.
Silicon carbide is one of the most promising materials for power electronic devices capable of operating at extreme conditions. The widespread application of silicon carbide power devices is however limited by the presence of structural defects in silicon carbide epilayers. Our experiment demonstrates that optical second harmonic generation imaging represents a viable solution for characterizing structural defects such as stacking faults, dislocations and double positioning boundaries in cubic silicon carbide layers. X-ray diffraction and optical second harmonic rotational anisotropy were used to confirm the growth of the cubic polytype, atomic force microscopy was used to support the identification of silicon carbide defects based on their distinct shape, while second harmonic generation microscopy revealed the detailed structure of the defects. Our results show that this fast and noninvasive investigation method can identify defects which appear during the crystal growth and can be used to certify areas within the silicon carbide epilayer that have optimal quality.
碳化硅是最有前途的材料之一，可用于能够在极端条件下运行的电力电子设备。然而，碳化硅功率器件的广泛应用受到碳化硅外延层中存在结构缺陷的限制。我们的实验表明，光学二次谐波成像是一种可行的方法，可用于表征立方碳化硅层中的结构缺陷，如堆垛层错、位错和双定位边界。X 射线衍射和光学二次谐波旋转各向异性用于确认立方多型的生长，原子力显微镜用于基于其独特的形状支持碳化硅缺陷的识别，而二次谐波产生显微镜则揭示了缺陷的详细结构。我们的结果表明，这种快速、非侵入式的研究方法可以识别晶体生长过程中出现的缺陷，并可用于验证碳化硅外延层中具有最佳质量的区域。
