Semiconductor SERS on Colourful Substrates with Fabry-Pérot Cavities

Area of Science:

• Materials Science
• Nanotechnology
• Spectroscopy

Background:

• Non-metallic materials offer unique advantages as substrates for surface-enhanced Raman scattering (SERS).
• However, their lower Raman enhancement compared to metals limits their application.
• Inefficient light interaction in non-metallic SERS substrates necessitates improved designs.

Purpose of the Study:

• To develop novel semiconductor-based SERS substrates with enhanced sensitivity.
• To utilize a Fabry-Pérot cavity to manipulate light-matter interactions for non-metallic SERS.
• To achieve a significantly lower detection limit for analytes using semiconductor SERS.

Main Methods:

• Fabrication of semiconductor-based SERS substrates incorporating a Fabry-Pérot cavity.
• Optimization of resonant absorption by tuning frequency and intensity.
• Demonstration of SERS detection using a SiO₂/Si Fabry-Pérot substrate with SnS₂ for SARS-CoV-2S protein detection.

Main Results:

• Achieved resonant absorption in various non-metal SERS substrates through precise light manipulation.
• Enhanced SERS sensitivity by approximately 100 times compared to conventional non-metallic substrates.
• Attained a record low detection limit of 10⁻¹⁶ M for SARS-CoV-2S protein using the proposed substrate.

Conclusions:

• The proposed Fabry-Pérot cavity strategy effectively enhances SERS sensitivity for non-metallic semiconductor substrates.
• This approach provides a viable method for increasing the sensitivity of semiconductor-based SERS.
• The developed substrates show great potential for sensitive detection of biomarkers like SARS-CoV-2S protein.