Atomistic simulations of deposition and growth of SiC crystal on 4H-SiC (0001) Si-face substrate

Monocrystalline 4H-SiC attracts significant attention as a semiconductor material due to its excellent physical and chemical properties. As such, it is emerging as a promising choice in power devices offering superior performance to traditional Si-based devices. The film growth quality of 4H-SiC is recognized as a critical factor in the device manufacturing process, directly impacting device performance. In the present work, the deposition and growth process of silicon carbide from the gaseous phase onto a 4H-SiC substrate is studied in atomistic simulations for on-axis, and various degrees of off-axis (0001) Si-face substrates in a broad range of temperature. The molecular dynamic simulations are targeted at revealing the fundamental microscopic mechanism of crystal nucleation and growth of different SiC polytypes, dislocation defect formation, and surface morphology. The key characteristics such as the crystal growth rate, dislocation density, and the internal stress of the deposited atoms are calculated depending on the deposition temperature. Major results show that on-axis growth yields a 3C-SiC polytype film, while for off-axis growth, on-demand optimization of the microstructure of the 4H-SiC films can be performed by tuning the substrate temperature and off-axis degree.