Accuracy of tip-sample interaction measurements using dynamic atomic force microscopy techniques: Dependence on...

Area of Science:

• Surface Science
• Nanotechnology
• Physical Chemistry

Background:

• Atomic force microscopy (AFM) is a key technique for high-resolution surface topography and chemical property mapping.
• Dynamic AFM methods analyze cantilever oscillations to quantify tip-sample forces and interaction potentials.
• Current conversion methods can introduce errors when oscillation amplitudes approach interaction decay lengths.

Purpose of the Study:

• To investigate the impact of oscillation amplitude on the accuracy of dynamic AFM force measurements.
• To identify factors influencing systematic errors in tip-sample interaction quantification.
• To propose a method for mitigating these measurement errors.

Main Methods:

• Computational study simulating dynamic AFM measurements.
• Analysis of tip-sample interaction potentials and force conversions.
• Systematic variation of oscillation amplitude, interaction strength, and distance.

Main Results:

• Errors in force quantification are non-negligible when oscillation amplitudes are comparable to the interaction decay length.
• The degree of error is critically dependent on interaction strength and measurement distance.
• Systematic errors can be effectively eliminated by employing oscillation amplitudes significantly larger than the decay length.

Conclusions:

• The accuracy of dynamic AFM force measurements is highly sensitive to the chosen oscillation amplitude.
• Careful selection of oscillation amplitude, relative to interaction decay length, is crucial for reliable surface chemistry analysis.
• Utilizing larger oscillation amplitudes offers a straightforward method to enhance the precision of AFM-based force quantification.