ABSTRACT
Marc Chaigneau,a Giovanni Maria Vanacore,b* Monica Bollani,c
Gennaro Picardi,a Alberto Tagliaferri,b
In this chapter, we describe the determination of the stress profile
in 150 nm-wide SiGe nano-stripes embedded into a Si matrix by
using oblique incidence tip-enhanced Raman spectroscopy (TERS)
with a spatial resolution of ∼20 nm. The TERS spectra of the stripes exhibit a number of locally enhanced phonon modes that are
absent when the tip is positioned out of the stripes. The hydrostatic
stress component across the nano-stripe width is evaluated from
the strain-induced frequency shift of the Si-Ge mode at ∼380 cm−1. The stress magnitude is found to be largest in the nano-stripe
center and decreases monotonously on each side down to zero
at the boundaries. This behavior is quantitatively described by a
classic continuous medium model. These results demonstrate the
applicability of the TERS technique to stress determination in novel
semiconductor structures at the nanometer scale.
