Calibration of piezo actuators and systems by dynamic interferometry

Area of Science:

• Physics
• Materials Science
• Nanotechnology

Background:

• Precise positioning of components is essential for non-contact atomic force microscopy (AFM) measurements.
• Piezo actuators, such as tube piezos, are commonly used for high-accuracy positioning of the AFM tip or optics.

Purpose of the Study:

• To develop and validate a novel calibration method for piezo actuators in AFM.
• To calibrate the fine-positioning z-piezo and cantilever oscillation amplitude using dynamic response signals.

Main Methods:

• Utilized a fiber interferometer for cantilever displacement detection.
• Analyzed the dynamic interferometer response signal under varying cantilever oscillation amplitudes and distances.
• Recorded data for different tube piezo contractions and extensions.

Main Results:

• Successfully calibrated the fine-positioning z-piezo based on the dynamic interferometer response.
• Demonstrated accurate calibration of cantilever oscillation amplitude.
• Evaluated the accuracy, merits, and limitations of the proposed calibration approach.

Conclusions:

• The proposed method offers a reliable approach for calibrating piezo actuators in AFM.
• This technique enhances the precision of displacement measurements in AFM applications.
• The study discusses the practical implications and accuracy boundaries for this calibration method.