1 research outputs found
Nucleation and Atomic Layer Reaction in Nickel Silicide for Defect-Engineered Si Nanochannels
At the nanoscale, defects can significantly
impact phase transformation
processes and change materials properties. The material nickel silicide
has been the industry standard electrical contact of silicon microelectronics
for decades and is a rich platform for scientific innovation at the
conjunction of materials and electronics. Its formation in nanoscale
silicon devices that employ high levels of strain, intentional, and
unintentional twins or grain boundaries can be dramatically different
from the commonly conceived bulk processes. Here, using in situ high-resolution
transmission electron microscopy (HRTEM), we capture single events
during heterogeneous nucleation and atomic layer reaction of nickel
silicide at various crystalline boundaries in Si nanochannels for
the first time. We show through systematic experiments and analytical
modeling that unlike other typical face-centered cubic materials such
as copper or silicon the twin defects in NiSi<sub>2</sub> have high
interfacial energies. We observe that these twin defects dramatically
change the behavior of new phase nucleation and can have direct implications
for ultrascaled devices that are prone to defects or may utilize them
to improve device performance