Topography Frequency:

• The first flexural mode of the cantilever is excited mechanically.

• This frequency is used to measure and control the sample topography.

• Allows for precise tracking of surface features without interference

Surface Potential Frequency:

• The second flexural mode of the cantilever is excited electrically.

• This separate frequency is dedicated to measuring surface potential.

• Enables simultaneous, independent measurement of topography and surface

Signal Amplification:

• The use of the second eigenmode for electrical excitation inherently amplifies the signal.

• This amplification occurs even with very small applied AC voltages.

• Results in improved signal-to-noise ratio and higher sensitivity to small potential differences.

Enhanced Signal Amplification:

• The VAC bias is fine-tuned to the second eigenmode of the cantilever.

• This tuning amplifies the signal by the Q factor of the second mode.

• The Q factor amplification can be significant, often 100 times or more, greatly enhancing sensitivity.

Improved Stability:

• The second eigenmode has a stiffer effective spring constant compared to the fundamental mode.

• This increased stiffness provides more stable oscillation during surface scanning.

• Stability translates to more reliable and consistent measurements, especially on challenging samples.

Automated Frequency Optimization:

• The Vac bias is fine-tuned to the Second eigenmode automatically by the software without user intervention.

• Patented algorithm selects the best frequency position around the resonance peak.

• Achieves better resolution and sensitivity through optimized frequency selection.