Dislocations in 4H-SiC epilayers for power devices: Identification, formation, and regulation

4H-SiC is highly promising for modern electronics, particularly in high-temperature, high-frequency, and highpower applications. However, the presence of dislocations in 4H-SiC epilayers significantly affects the performance and reliability of 4H-SiC-based power devices, thus limiting their widespread application. This review provides an overview of the classification, fundamental properties, and inspection methods of dislocations in 4HSiC epilayers. The mechanisms of dislocation nucleation, propagation, and conversion during epitaxial growth are presented. Furthermore, strategies to mitigate dislocations, with a particular focus on enhancing the efficiency of BPD-TED conversion, are comprehensively discussed. By offering insights into dislocation behavior in 4H-SiC epilayers, this review highlights the challenges and emerging directions in the study of dislocations.