Near-zero contact force atomic force microscopy investigations using active electromagnetic cantilevers.

Area of Science:

• Surface Science
• Nanotechnology
• Microscopy

Background:

• Atomic Force Microscopy (AFM) is a high-resolution surface imaging technique.
• Contact AFM (C AFM) mode involves continuous tip-sample contact.
• Active cantilever technology offers enhanced control and precision.

Purpose of the Study:

• To implement active electromagnetic cantilevers in AFM for improved surface characterization.
• To explore the capabilities of electromagnetic actuation for cantilever control.
• To develop and apply a novel control algorithm for precise force management.

Main Methods:

• Utilized active electromagnetic cantilevers with integrated conductive loops.
• Applied an electric current in a magnetic field to generate Lorentz force for cantilever deflection.
• Developed and implemented the PredPID control algorithm for precise load force maintenance.
• Calibrated probe stiffness with reduced uncertainty.

Main Results:

• Demonstrated precise excitation and control of cantilever deflection using electromagnetic actuation.
• Achieved accurate estimation of Lorentz force for cantilever manipulation.
• Successfully applied the PredPID algorithm to maintain constant load force.
• Showcased improved probe stiffness calibration compared to standard methods.

Conclusions:

• Active electromagnetic cantilevers represent significant progress in AFM technology.
• The PredPID algorithm enables advanced control for high-sensitivity surface measurements.
• This approach offers enhanced precision and reduced uncertainty in AFM applications.