Accurate Extraction of Electrostatic Force by a Voltage-Pulse Force Spectroscopy

Area of Science:

• Physics
• Materials Science
• Nanotechnology

Background:

• Accurate characterization of interaction forces is crucial across diverse scientific disciplines.
• Electrostatic forces (F(ele)) are significant but challenging to isolate and quantify.
• Conventional atomic force microscopy (AFM) has limitations in measuring distance-independent forces.

Purpose of the Study:

• To introduce a novel method for unambiguous extraction of electrostatic force (F(ele)).
• To enable quantitative measurement of F(ele) as a function of tip-sample distance and applied voltage.
• To provide a new approach for characterizing tip geometry and contact potential difference.

Main Methods:

• Utilizing energy dissipation measurements under applied voltage pulses between an AFM tip and sample.
• Applying a modified AFM technique to isolate and quantify electrostatic forces.
• Developing an analytical model for fitting experimental F(ele) data.

Main Results:

• Successfully extracted F(ele) with high accuracy, including distance-independent components.
• Demonstrated that the method is sensitive to tip-sample distance and voltage.
• Obtained precise tip geometry estimations and distance-dependent contact potential difference values.
• Showcased the method's capability to quantitatively measure electrostatic forces.

Conclusions:

• The proposed method offers an unambiguous way to measure electrostatic forces (F(ele)).
• This technique enhances AFM capabilities for nanoscale force characterization.
• It provides a new pathway for quantitative Kelvin probe force microscopy and surface analysis.