Mechanism of stacking fault annihilation in 3C-SiC epitaxially grown on Si(001) by molecular dynamics simulations

In this work, the annihilation mechanism of stacking faults (SFs) in epitaxial 3C-SiC layers grown on Si(001) substrates is studied by molecular dynamics (MD) simulations. The evolution of SFs located in the crossing ((1) over bar 11) and (1 (1) over bar1) glide planes is considered. This evolution is determined by the interaction of 30 degrees leading partial dislocations (PDs) limiting the stacking faults under the slightly compressive (similar to 0.45%) strain condition during the 3C-SiC layer growth. it is characterized in key terms: the distance between the PDs and the mutual orientation of their Burgers vectors. Two SF annihilation scenarios are revealed. in the first scenario, two PDs with opposite screw components of Burgers vectors, leading the SFs located in the ((1) over bar 11) and (1 (1) over bar1) planes, are close enough (similar to 15 nm or less) and attract each other. As a result, the propagation of both SFs is suppressed via the formation of a Lomer-Cottrell lock at their intersection. In the second scenario, two PDs are far away one from the other (beyond similar to 15 nm) and do not interact or they repulse each other having equal screw components of their Burgers vectors in this case, the propagation of only one of the SFs is suppressed. Obtained results explain the mechanism of SF annihilation and formation of SF intersection patterns experimentally observed by TEM investigations. They will provide important implications for the elaboration of advanced methods for the reduction of SF concentrations in epitaxial 3C-SC layers on Si substrates.

Automated summary

The annihilation mechanism of stacking faults (SFs) in epitaxial 3C-SiC layers grown on Si(001) substrates was studied using molecular dynamics simulations. Two SF annihilation scenarios were revealed under slightly compressive strain conditions, showing how the interaction of partial dislocations affects the evolution of SFs. These results provide insights into the reduction of SF concentrations in epitaxial 3C-SC layers on Si substrates.