Sensitivity Improvement to Active Piezoresistive AFM Probes Using Focused Ion Beam Processing

Area of Science:

• Materials Science
• Nanotechnology
• Surface Science

Background:

• Active piezoresistive atomic force microscopy (AFM) cantilevers are crucial for high-resolution, high-speed surface measurements.
• Improving deflection sensitivity is key to enhancing AFM performance.

Purpose of the Study:

• To model and experimentally verify modifications to active piezoresistive AFM cantilevers.
• To increase cantilever deflection sensitivity with minimal impact on stiffness and resonance frequency.

Main Methods:

• Utilized focused ion beam (FIB) technology to modify cantilever structures integrating Wheatstone piezoresistors.
• Employed finite element modeling (FEM) to guide the FIB modification process.
• Integrated an actuator for precise deflection and assessment of sensor properties.

Main Results:

• Achieved a 2.5-fold increase in deflection sensitivity.
• Verified the results through calibration routines and analytical calculations.
• Demonstrated minimal influence on cantilever stiffness and resonance frequency.

Conclusions:

• The proposed FIB modification procedure effectively enhances active piezoresistive AFM cantilever deflection sensitivity.
• This technique offers a viable method for improving AFM performance for advanced surface analysis.
• The integrated deflection monitoring ensures reliable sensor property assessment.