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.
20 nm-Resolved Stress Profile in SiGe Nano-Stripes Obtained by Tip-Enhanced Raman Spectroscopy
Bollani Monica;
2016
Abstract
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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
