Impurities and defects in 4H silicon carbide

The widespread use of 4H silicon carbide (4H-SiC) is just around the corner since high-power electronics based on 4H-SiC are increasingly fabricated to enable the low-carbon development of the world. Quantum technologies are also intensively explored by scrutinizing 4H-SiC as a platform for wafer-scale integration of semiconductor and quantum technologies. Given the importance of impurities and defects for any semiconductor, comprehensive and insightful understanding of impurities and defects in 4H-SiC is imperative. In this Perspective, we summarize recent experimental and theoretical advances in researches on impurities and defects in 4H-SiC after briefly reviewing the history of 4H-SiC. Impurity engineering and defect engineering for the realization of the full potential of 4H-SiC are also discussed. Challenges for the study on impurities and defects in 4H-SiC are finally outlined.