AFM indentation - force constant

[elsva]

Anyone have any reference or experience as to in which range the force constant of the cantilever should be for carrying out AFM indentation on CNT? (in UVH).

Thanks,
E.S

 

[Lateralis]

AFM in UHV... You don't have one of those really fancy UHV STM/AFM heads, do you? =P

Anyway, in contact mode the typical forces exerted are of the order 10nN. If you know the area of the tip that is making contact you can then work out what the pressure exerted is. Similarly, you can work backwards; if you know what the bulk modulus of the CNTs is, you can work out what sort of force you need to apply in order deform it. If you guess what the final tip radius might be you can work out roughly what contact force you need to apply to get roughly the right pressure.

... Maybe!