Instruction manual

Rev. B MultiMode SPM Instruction Manual 167
Chapter 10 Lateral Force Mode
The MultiMode SPM is capable of measuring frictional forces on the surfaces of samples using a
special measurement known as lateral force microscopy (LFM). The name derives from the fact
that cantilevers scanning laterally (perpendicular to their lengths) are torqued more as they transit
high-friction sites; low-friction sites tend to torque cantilevers less. The relative measure of lateral
forces encountered along a surface yields a map of high- and low-friction sites.
After obtaining a good topographical image in Contact Mode, it is relatively easy to use LFM to
view and acquire lateral force data. It is important to obtain a good image in Contact mode before
measuring LFM data. The NanoScope system will continue to run the feedback based on measuring
the vertical deflection signal and feedback gains in the control panel while LFM data is acquired
and displayed.
The following sections are included in this chapter:
• Basic LFM Operation: Section 10.1
• Advanced LFM Operation: Section 10.2
• Scan Direction: Section 10.2.1
• Tip selection: Section 10.2.2
• Understanding the LFM Signal: Section 10.2.3
• Understanding the Color Scale: Section 10.2.4
• Using TMR Voltage to Measure Friction: Section 10.2.5
• Enhancing the LFM Data by Subtracting Two Images: Section 10.2.6
• Height Artifacts in the Signal: Section 10.2.7
Lateral Force
Mode