Optimization of Ag coated hydrogen silsesquioxane square array hybrid structure design for surface-enhanced Raman...

Area of Science:

• Materials Science and Engineering
• Nanotechnology
• Computational Physics

Background:

• Surface-enhanced Raman scattering (SERS) is a powerful technique for ultrasensitive molecular detection.
• Optimizing SERS substrate design is crucial for enhancing detection sensitivity and reproducibility.
• Existing design methods can be time-consuming and may not explore the full design space.

Purpose of the Study:

• To propose a computer-automated design process for SERS substrates.
• To utilize particle swarm optimization to tailor nanostructured silver (Ag) coated hydrogen silsesquioxane nanopillar arrays.
• To provide a systematic approach for achieving optimum SERS substrate performance.

Main Methods:

• Fabrication of nanostructured Ag-coated hydrogen silsesquioxane nanopillar arrays via direct Ag film deposition on electron beam lithography-patterned substrates.
• Systematic investigation and characterization of the fabricated SERS substrates.
• Finite-difference time-domain (FDTD) simulations to calculate absorption spectra, charge distributions, and electric field distributions.

Main Results:

• Demonstrated good agreement between experimental results and FDTD simulations.
• Identified plasmon resonance as the origin of electric field enhancement.
• Validated the effectiveness of the particle swarm optimization algorithm in guiding SERS substrate design.

Conclusions:

• The proposed computer-automated design process, leveraging particle swarm optimization, is effective for optimizing SERS substrates.
• The study provides a clear understanding of the field enhancement mechanism in the designed nanostructures.
• This work offers a valuable guide for the rational design of high-performance SERS substrates.