1 research outputs found
Defect-Free Erbium Silicide Formation Using an Ultrathin Ni Interlayer
An
ultrathin Ni interlayer (∼1 nm) was introduced between
a TaN-capped Er film and a Si substrate to prevent the formation of
surface defects during thermal Er silicidation. A nickel silicide
interfacial layer formed at low temperatures and incurred uniform
nucleation and the growth of a subsequently formed erbium silicide
film, effectively inhibiting the generation of recessed-type surface
defects and improving the surface roughness. As a side effect, the
complete transformation of Er to erbium silicide was somewhat delayed,
and the electrical contact property at low annealing temperatures
was dominated by the nickel silicide phase with a high Schottky barrier
height. After high-temperature annealing, the early-formed interfacial
layer interacted with the growing erbium silicide, presumably forming
an erbium silicide-rich Er–Si–Ni mixture. As a result,
the electrical contact property reverted to that of the low-resistive
erbium silicide/Si contact case, which warrants a promising source/drain
contact application for future high-performance metal–oxide–semiconductor
field-effect transistors