Mapping Analysis of Single Crystal SiC Polytypes Grown From Purified β-SiC Powder

摘要

The most important consideration when growing single crystal silicon carbide by the physical vapor transport method is to minimize defects. To minimize defects caused by temperature gradient, we used β phase SiC powder, which has a low sublimation temperature, and purified the β phase SiC powder to improve the purity of single crystal SiC. Furthermore, we performed thermodynamic computational simulations based on compositions of purified and non-purified β-SiC powders to study the impact of metallic impurities within SiC powder on the composition of single crystal SiC. We grew SiC at temperatures about 200 °C lower than the previous growth temperature using purified β-SiC powder and mapped the phase change behavior of SiC according to different growth temperatures. Moreover, we compared and analyzed the characteristics of SiC polytype formation and crystallinity according to growth temperature. We compared the distribution of defects and dislocations of single crystal 4H SiC grown from purified and non-purified β-SiC powder to study the impact of source purification on defect generation. We also investigated the effect of metallic impurities on the formation of defects and dislocations through content analysis of metallic impurities.