Demystifying Atomic Force Microscopy Vibrating Mode Techniques
AFMWorkshop's series of animated tutorials on the Basics of Atomic Force Microscopes have been a huge hit around the world. Today we're pleased to release the second series of animations, featuring Vibrating Mode Techniques.
Vibrating mode is available in most commercial Atomic Force Microscopes, and is given a variety of names including:
The myriad of names is confusing to many AFM operators, and is one of several reasons why "vibrating mode" can be intimidating to those learning about AFMs for the first time.
In the original Atomic Force Microscope, the loading force of a probe on a surface was held constant by monitoring the defection of a cantilever with a probe on its free end. Using a cantilever with a very low force constant, on the order of 1 nanonewton/nanometer, probes with just a few nanometers in diameter were not broken while making surface profiles. The first AFMs were constructed using this direct deflection technique, but soon after their introduction it was discovered that even lighter loading forces could be achieved by vibrating the cantilever and then measuring changes in the vibration amplitude while scanning.
Operating an AFM in vibrating mode is more difficult than operating the AFM in non-vibrating mode. This is because there are several parameters that can be controlled in vibrating mode, and the loading forces between the probe and sample are about the same as the interaction force between the probe and surface contamination layer.
AFMWorkshop's new series of animations aims to ease some of the challenges of operating in vibrating.
