Physico-Chemical Nanomaterials Science

Molecular Dynamics Simulation of the Formation of Extended Defect Structure in 3C-SiC Thin Films on Si(001) Substrates
Sarikov A.1, Marzegalli A.2, Barbisan L.3, Scalise E.3, Montalenti F.3,  Miglio L.3
1 V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine. 41 Nauki avenue, 03028 Kyiv, Ukraine. 
E-mail: sarikov@isp.kiev.ua
2 L-NESS and Department of Physics, Politecnico di Milano, via Anzani 42, 22100 Como, Italy.
3 L-NESS and Department of Materials Science, University of Milano-Bicocca, via R. Cozzi 55, 20125 Milan, Italy.

Thin films of cubic silicon carbide (3C-SiC) epitaxially grown on Si(001) substrates are promising for power device applications. However, the electronic quality of such films is strongly affected by large amount of extended defects, such as stacking faults (SFs) and partial dislocations (PDs), formed during film growth. 
This work presents the results of a detailed study of the formation of extended defect configurations during growth of 3C-SiC films on Si(001) substrates using molecular dynamics (MD) simulations. First, a synergetic approach based on the application of the Vashishta and the analytical bond order potentials for simulation of large-scale PD and SF transformations, and the local atomic configurations of dislocation cores, respectively, is proposed and validated. Using this approach, the evolution and interaction of partial dislocations and stacking faults are simulated as directly related to the 3C-SiC growth technology. The processes under study are described in terms of the orientations of the Burgers vectors and mutual arrangements of partial dislocations terminating stacking faults. A number of experimentally observed phenomena are explained including: (i) stabilization of multiple stacking faults by PD complexes, leading to the formation of hexagonal SiC inclusions (4H and 6H) in 3C-SiC, (ii) formation of preferential shapes of multiple SFs; and (iii) annihilation of stacking faults with formation of characteristic SF intersection patterns. Obtained results provide a comprehensive understanding of how the technological conditions of growing epitaxial 3C-SiC films on Si(001) substrates result in the experimentally observed extended defect configurations in them. These results are important for further development of 3C-SiC growth technology to improve the electronic quality of obtained films.