AFM

Applications

• Analysis of all types of materials : polymers, biological samples, powders, metals, glass, …
• Tridimensional morphological analysis
• Roughness parameters measurements
• Cartography of adhesives / viscoelastical properties
• The maximum observable area is 170x170 µm². To observe bigger areas or a larger clearance in z, we will prefer an optical profilometer.

How it works

Contact, Tapping, Peak Force Tapping, Peak Force QNM, Conductive AFM, Scanning Capacitance Microscopy
The AFM principle rely on the measurement of different interaction forces between atoms of the surface to observe and atoms of the tip. The working mode is chosen according to the information we want to obtain from the surface to analyse.

The topographical image can be coupled to mapping of certain phsical properties of materials:

• Friction force , adhesive forces, elasticity modulus, dissipation
• Magnetic power, electrostatics, conductivity, capacity

TESCAN ANALYTICS has also developed a stretching module to observe through AFM the evolution of polymer films morphology under a mechanical constraint.



The tip is fixed under a cantilever, of a determined stiffness. The sample is put on a piezoelectric ceramic material controling movings in the 3 directions X, Y, Z. When the sample is brought near the tip/sample, interaction forces tip/sample cause a deflection of the cantilever proportional to the force intensity. A laser beam, reflected on the back side of the cantilever and directed on a photodiode 4-quadrants, measures that deflection.

In the first historical mode, the  « contact mode », the deflection of the cantilever is maintained constant with a control loop while the sample is moved in X, Y and Z. A 3D topographical image is obtained.