 The atomic force microscope
(AFM) images features on the scale of several Angstroms, nanometers and microns. It is most commonly used
to measure topography — profiles of surfaces. An AFM can also be configured to measure other forces, for
example: magnetic, electrostatic, adhesive and elastic. By measuring very localized forces over a
surface, a map of the surface is produced. By associating the force map with topography,
structure-property correlations can be drawn. With the ability to sample forces over very small areas of
Angstroms or nanometers, the AFM is an important instrument in documenting the scaling of properties from
the traditional 'macroscopic' regime down to the regime of collections of several molecules.
AFM Modes
| Microscopy Mode | | Motion | Cause |
AFM
Atomic Force
or
SPM
Scanning Probe
|
|
Tracking
|
Topography
|
LFM
Lateral Force
or
FFM
Friction Force
|
|
Twisting
|
Friction
|
|
Force Modulation
|
|
Bouncing
|
Elasticity
Viscosity
|
Force-Distance
Curves
|
|
Sticking
|
Adhesion
|
Our AFM instrumentation operates in several modes: contact, intermittent contact, noncontact and
nonscanning. Samples of many different dimensions are accommodated nondestructively on AFM's with both
small and large sample stages.
 Two large-stage atomic force microscopes (AFM): contact, intermittent contact, and non-contact
imaging modes; one with x,y-stage and one with either (r,Theta) or rotary stage. Two small-stage atomic force
microscopes (AFM): contact, intermittent contact, and non-contact imaging modes; solution cell;
scanners: 5µm, 100µm, and closed loop. Lab's capabilities also include conductive and magnetic
force imaging.
|
