On the importance of precise calibration techniques for an atomic force microscope

Area of Science:

• Materials Science
• Nanotechnology
• Physics

Background:

• Accurate instrument calibration is essential for quantitative scientific research.
• Atomic Force Microscopes (AFMs) require precise knowledge of parameters like probe spring constant and piezoactuator response for data interpretation.
• Manufacturer-provided values may introduce significant uncertainty.

Purpose of the Study:

• To adapt and apply existing techniques for quantifying critical AFM parameters.
• To compare instrument parameters determined through recalibration with manufacturer-specified values.
• To assess the impact of parameter uncertainty on experimental results.

Main Methods:

• Adaptation of established methods for quantifying probe spring constant, piezoactuator voltage/height response, and probe radius of curvature.
• Direct measurement and calculation of these parameters specific to the experimental setup.
• Calculation of total statistical uncertainty using both manufacturer and recalibrated values.

Main Results:

• Significant discrepancies were found between manufacturer-provided and recalibrated instrument parameters.
• Using manufacturer values, the total statistical uncertainty was over 1500%.
• Recalibration reduced the contribution of these parameters to the total uncertainty to approximately 20%.

Conclusions:

• Proper, in-situ calibration of AFM parameters is critical for accurate data analysis.
• Underestimating parameter uncertainty can lead to unreliable quantitative results.
• Understanding and quantifying instrument-specific parameters enhances the credibility and reproducibility of AFM experiments.