Modified AFM sensor [1] [2]

This is a classic AFM not adapted to measure surface topography but rather a measure of pull-off forces, surface tension, etc... (fig. 1)

Figure 1: atomic force microscope used for Nanorol.

Features :

• stiffness of cantilever used between 0.03 N/m and 14 N/m
• a cantilever of stiffness 0.2 N/m allows a measure of 0 to 600 nN with a resolution of 10 nN
• cantilever stiffness calibration by excitation of eigen modes, or thermal noise measurement
• measure of a two direction force using the 4 framework photodiode

Known limitations:

• coupling movement of the tip of the cantilever generating unexpected behavior in the process of withdrawal and approach between the tip and the substrate, mainly during the phases of contact
• calibration of the deflection measurement of the lever by the photodiode uncertain