Basic LFM Operation

This section outlines the basic operational procedures involved in obtaining data in Lateral Force Mode. Before attempting to take LFM images, you should be familiar with taking Contact AFM mode images with the Dimension Icon. Ensure that the system is installed and set up correctly.

Probe Requirements

LFM is typically performed with low spring constant silicon nitride "A" shaped cantilevers.

After performing Contact Mode imaging, LFM images may be taken without interrupting the imaging session.

HINT: The Contact Mode setpoint

voltage will affect the magnitude of the lateral force signal. If the frictional effects are too large or too small, change the cantilever. But if the value is near the dynamic range desired, adjustment of the Contact Mode setpoint voltage will produce modest changes in the lateral force or frictional signal. By increasing the setpoint, the contact force applied will increase, and so will the frictional or torsional forces in an approximately linear fashion.

Steps to acquiring LFM data:

1. Set Up the Experiment

2. Load a probe.

3. Align the laser and photodetector.

4. Locate the probe tip for the software.

5. Using the Navigate view, load a sample and focus the optics on the sample surface.

6. Using the Check Parameters view, review the preloaded scan parameters and modify them as needed.

7. Engage on the sample and scan.

	In the Scan view, suggested parameter settings are as follows:
	Scan list: Scan Rate: 1 Hz Scan Size: 500 nm Scan Angle: 90.0 degrees
	Feedback list: Integral gain: 2 Proportional gain: 5 Deflection Setpoint: 30.00 nm
	Other list: Units: Metric
	In the main window, the channel settings should be as follows: Channel 1 Data Type: Height Channel 2 Data Type: Friction Channel 3 Data Type: Deflection Error Set Data Scale to a reasonable value for the sample. For example, for a 200 nm step height calibration sample, a reasonable initial Data Scale setting is 300 nm. Channel 2 Line direction: Trace NOTE: If the Line Direction parameter is changed to Retrace, the plus-minus sign of the lateral force changes and low lateral force will be displayed on the top of the scope display. Setting the scan angle to 270 degrees will invert the polarity of Trace and Retrace. Channel 4 through Channel 8 Data Type: Off

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	Click the Select Experiment icon to open the Select Experiment window
	Select the following: Experiment Category: Contact Mode Experiment Group: Lateral Force Microscopy (LFM) Select Experiment: Lateral Force Microscopy (LFM)
	Click Load Experiment.

Basic LFM Operation

Probe Requirements

Steps to acquiring LFM data:

Scan list:

Feedback list:

Other list: