Atomic study on deformation behavior and anisotropy effect of 4C-SiC during nanoindentation

4H-SiC is widely accepted as a potential candidate for advanced electronic devices due to its superior electron mobility and wide bandgap. However, the lack of understanding on its mechanical properties has hindered its manufacturing and application. Herein, nanoindentation simulations are performed to explore the deformation behavior and anisotropy of 4H-SiC. The results reveal that the main mechanism for elastic deformation of 4H-SiC is the expansion of elastic distortion stacks along < 1100 > directions, while the nucleation and prop-agation of the perfect and partial dislocation loops in 4H-SiC is the dominant way for its plastic deformation, and the perfect dislocation loops tend to be formed near the indented surface. In addition, 4H-SiC exhibits strong anisotropy when the orientation angle of the corner cubic indenter is changed. The perfect and partial dislocation loops are more likely to be generated as the indenter ridge is parallel to 4H-SiC < 1100 > direction (theta = 0 degrees). The stress analysis indicates that more shear stress and deformation energy are stored in the elastic distorted area for theta = 90 degrees, thus hindering the nucleation and propagation of dislocations. This research provides valuable insights into the mechanical behavior of 4H-SiC, which is essential for its manufacturing and application in industry.