SNOM/STM using a tetrahedral tip and a sensitive current-to-voltage converter

Area of Science:

• Nanoscale science and technology
• Optical microscopy
• Surface science

Background:

• Scanning near-field optical microscopy (SNOM) with tetrahedral-tips (T-tips) has demonstrated high resolution on metallic samples.
• Previous SNOM/STM setups were limited to metallic samples due to standard current-to-voltage converters.
• The optical potential of T-tips suggests applicability to non-metallic systems, but this requires further investigation.

Purpose of the Study:

• To develop a new SNOM/STM transmission mode setup utilizing a T-tip.
• To enable the analysis of non-metallic sample systems, including organic monolayers.
• To improve mechanical and optical conditions for routine nanoscale investigations.

Main Methods:

• Implementation of a sensitive current-to-voltage converter for broader sample compatibility.
• Design and utilization of a novel SNOM/STM transmission mode setup with a T-tip.
• Substantial improvements in mechanical stability and optical measurement conditions.

Main Results:

• The new setup successfully extends SNOM/STM capabilities to non-metallic samples.
• Achieved resolutions in the 10 nm range for metal nanostructures and organic monolayers.
• Demonstrated enhanced performance and reliability compared to previous setups.

Conclusions:

• The developed SNOM/STM transmission mode setup with a T-tip is effective for analyzing diverse nanoscale materials.
• This advancement provides a foundation for routine high-resolution studies of organic and metallic nanostructures.
• The sensitive current-to-voltage converter is key to expanding the range of measurable samples.