中文摘要：

由于在研究SiC晶体缺陷对器件性能的影响的过程中,表征材料缺陷的常用的方法是破坏性的,因此寻找一种无损的测试方法对缺陷进行有效的表征显得尤为重要。基于阴极荧光（CL）的工作原理对4H-SiC同质外延材料的晶体缺陷进行了无损测试研究。结果发现利用阴极荧光可以观测到晶体内部的堆垛层错、刃位错和螺位错以及基面位错,其阴极荧光图中的形貌分别为直角三角形、点状和短棒状。因此该方法成为SiC晶体缺陷的无损表征时的一种有效的测试方法。如果利用该方法对材料的衬底和外延层缺陷分别进行观测就能建立起衬底和外延层缺陷之间的某种联系,另外对器件工作前后的缺陷进行表征,建立器件工作前后缺陷之间的联系,就可以进一步地研究材料缺陷对器件性能影响的问题。

英文摘要：

As the general method of defect characterization is destructive, during the current research on the effect of defect on device, nondestructive defect characterization is important especially. The defects of 4H-SiC homoepitaxial layer had been observed and studied, based on the principle of cathodoluminescence（CL）. The results show that the intrinsic stacking faults （SFs）, threading edge dislocations（TEDs）, threading screw dislocations（TSDs） and basal plane dislocations（BPDs） can be observed by cathodoluminescence. The shape are rightangle triangle, dot and stick, repectively. So this method is available for nondestructive defect characterization. The correlation between 4H-SiC substrate defects and epilayer defects will be established if we characterize the defects of 4H-SiC wafers with and without an epilayer. In addition, if we characterize the defects of device before and after operation, the correlation between SiC defects of the devices before and after operation will be established, too.