Strained Silicon Technology: Non-Destructive High-Lateral-Resolution Characterization Through Tip-Enhanced Raman...

Area of Science:

• Materials Science
• Nanotechnology
• Spectroscopy

Background:

• Semiconductor industry faces challenges with miniaturization below 10 nm for metal-oxide-semiconductor field-effect transistors.
• Strained silicon technology enhances device performance by inducing strain in the silicon crystal lattice.
• Need for faster, non-destructive in-line characterization techniques in semiconductor manufacturing.

Purpose of the Study:

• Explore advanced spectroscopic techniques for semiconductor quality control and failure analysis.
• Investigate µ-Raman spectroscopy and tip-enhanced Raman spectroscopy (TERS) for nanoscale characterization.
• Demonstrate TERS's capability in analyzing strain and composition in advanced semiconductor materials.

Main Methods:

• Utilized µ-Raman spectroscopy to assess strain values and distributions in strained silicon layers.
• Employed tip-enhanced Raman spectroscopy (TERS), combining atomic force microscopy with Raman spectroscopy.
• Analyzed Raman peak position shifts in strained and unstrained silicon layers for chemical composition and strain estimation.

Main Results:

• µ-Raman spectroscopy provides strain insights but is limited by the Abbe diffraction limit.
• TERS overcomes diffraction limits, offering high lateral resolution for nanoscale analysis.
• TERS effectively characterized Si_0.7Ge_0.3 epitaxial layers on silicon-on-insulator, confirming nanoscale strain control.

Conclusions:

• TERS is a powerful, non-destructive technique for advanced semiconductor characterization.
• TERS enables precise nanoscale strain control and chemical composition analysis.
• The study demonstrates TERS's effectiveness and high lateral resolution for quality control in semiconductor manufacturing.