Highly efficient tip-enhanced Raman spectroscopy and microscopy of strained silicon

Area of Science:

• Spectroscopy
• Nanotechnology
• Materials Science

Background:

• Tip-enhanced Raman spectroscopy (TERS) enables nanoscale chemical imaging.
• Existing TERS systems face challenges in signal-to-noise ratio and sample versatility.

Purpose of the Study:

• To present a versatile TERS system with enhanced illumination and detection capabilities.
• To achieve high signal-to-noise Raman signals from material surfaces and interfaces.
• To enable nanoscopic investigation of both opaque and transparent samples.

Main Methods:

• Utilized an edge filter with tunable cutoff wavelength for efficient signal collection.
• Employed a depolarized TERS configuration for higher contrast.
• Designed a specialized tip for enhanced field enhancement and to eliminate tip-related Raman signals.
• Implemented dynamic instrument design for reflection and transmission modes.

Main Results:

• Achieved high signal-to-noise Raman signals from surfaces and interfaces.
• Demonstrated efficient illumination and detection in the visible range.
• Successfully investigated a thin strained silicon surface layer.
• Showcased the system's capability for both opaque and transparent samples.

Conclusions:

• The developed TERS system offers a versatile platform for nanoscopic material investigation.
• The integration of an edge filter and depolarized configuration significantly improves signal quality and contrast.
• The system's dynamic design enhances its applicability to a wider range of samples.