Veeco Dimension 3100, Manual

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Force Imaging
Force Plots–An Analogy
204 Dimension 3100 Manual Rev. D
• Force Calibration (TappingMode): Section 13.5
• Force Plots: Section 13.5.1
• Obtaining a Force Plot (TappingMode): Section 13.5.2
• High Contact Force: Section 13.5.3
• Tip Selection: Section 13.5.4
• Force Modulation: Section 13.6
• Introduction: Section 13.6.1
• Selecting a Force Modulation Tip: Section 13.6.2
• Operating Principle: Section 13.6.3
• Force Modulation Procedure: Section 13.6.4
• Notes About Artifacts: Section 13.6.5
• Force Modulation with ‘Negative LiftMode’: Section 13.7
• Set Interleave Controls: Section 13.7.1
• Obtain a TappingMode Image: Section 13.7.2
• Obtain a Negative LiftMode Force Modulation Image: Section 13.7.3
• Force Volume: Section 13.8
13.1 Force Plots–An Analogy
A force plot is an observation of tip-sample interactions which yields information regarding the
sample and tip. By way of analogy, suppose a materials researcher must determine how powerful
two different types of magnets are. One magnet is made of iron, the other is a stronger, so-called
“rare earth” magnet.
A simple way of measuring each magnet’s power would be to determine its pull upon a steel plate.
For example, the researcher could hang each magnet from a simple spring scale, “zero” the scale,
then lower the magnet toward a heavy steel plate. At regular distances from the plate, the amount of
pull shown on the scale is recorded. At some unique height above the plate, each magnet is attracted
strongly enough to attach itself to the plate. A plot of height, H, versus magnetic pull gives a
comparative index of each magnet’s power. Similarly, after attachment the researcher could pull
each magnet away from the plate and measure the pulling force at regular intervals until the magnet
breaks free. The pull-off point of each magnet gives an additional index of its holding power.
1
A
representation of this setup during a lowering cycle of one magnet is illustrated in Figure 13.1a .