Feedforward compensation of piezo nonlinearity for high-precision high-speed atomic force microscopy

Area of Science:

• Nanotechnology
• Surface Science
• Microscopy

Background:

• Atomic force microscopy (AFM) is crucial for nanoscale characterization.
• High-speed AFM allows real-time observation of nanoscale dynamics.
• Piezoelectric actuator nonlinearities cause significant image-scaling errors (20-30%) in AFM.

Purpose of the Study:

• To develop a simple, software-based method for correcting piezoelectric nonlinearity in AFM scanning.
• To improve the accuracy of quantitative dynamic structural measurements in AFM.
• To provide a solution compatible with high-speed AFM and other scanning probe systems.

Main Methods:

• A feedforward software-based method was developed to generate corrected scan waveforms.
• Four distinct sources of positioning error in piezo scanners were identified.
• The method was implemented to compensate for these identified errors.

Main Results:

• The proposed method achieved an order-of-magnitude improvement in positioning accuracy.
• The software-based approach corrected piezoelectric nonlinearities effectively.
• Image-scaling errors were significantly reduced, enabling more quantitative measurements.

Conclusions:

• A readily implementable, software-based method effectively corrects piezoelectric nonlinearity in AFM.
• The technique enhances positioning accuracy without compromising imaging speed, ideal for high-speed AFM.
• This approach is compatible with various AFM and scanning probe microscopy systems.