Characterization of atomic force microscope probes at low temperatures

Author :Alexandra Radenovic, Eva Bystrenova, Laurent Libioulle, Francesco Valle, George T. Shubeita, Sandor Kasas, and Giovanni Dietler
Publication :Journal of Applied Physics
Publisher :American Institute of Physics
Volume :94
Number :6
Pages :4210-4214
Year :2003

Different types of atomic force microscopy ~AFM! probes were characterized under ultrahigh
vacuum conditions and at low temperatures. Properties of AFM probes, such as the resonance
frequency, the spring constant and quality factor of cantilevers, depend on temperature. A typical
shift in the resonance frequency as a function of temperature was observed for all kinds of
cantilevers studied. This was related to the change in temperature of Young’s modulus of the
cantilever material. Moreover, force’distance curves acquired at low temperatures and on different
substrates, elucidate the importance of the hydrophobicity of the sample surface and that of the tips
for lowering adhesion forces. Finally, all of the probes were imaged in a scanning electron
microscope as a function of the temperature. A bending of the coated cantilever at low temperatures
was observed, which explains the peculiar force’distance curves. As a consequence, the use of
uncoated cantilevers for low-temperature applications is recommended.