  3C-SiC epitaxially grown on Si displays a large wealth of extended defects.
In particular, single, double and triple stacking faults (SFs) are observed in
several experiments to coexist. Overabundance of defects has so far limited the
exploitation of 3C-SiC/Si for power electronics, in spite of its several ideal
properties (mainly in terms of wide gap, high breakdown fields and thermal
properties) and the possibility of a direct integration in the Si technology.
Here we use a multiscale approach, based on both classical molecular dynamics
(MD) simulations and first-principle calculations, to investigate in-depth the
origin, nature and properties of most common 3C-SiC/Si(001) extended defects.
Our MD simulations reveal a natural path for the formation of partial
dislocation complexes terminating both double and triple SF's. MD results are
used as input for superior DFT calculations, allowing us to better determine
the core structure and to investigate electronic properties. It turns out that
the partial dislocation complexes terminating double and triple SFs are
responsible for the introduction of electronic states significantly filling the
gap. On the other hand, individual partial dislocations terminating single SFs
only induce states very close to the gap edge. We conclude that partial
dislocation complexes, in particular the most abundant triple ones, are killer
defects in terms of favoring leakage currents. Suggestions coming from
theory/simulations for devising a strategy to lower their occurrence are
discussed.
