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attoAFM III
tuning fork based, low temperature atomic force microscope
The attoAFM III is an atomic force microscope designed partic-
ularly for applications at low and ultra low temperature. Due to
the non-optical shear force detection based on a tuning fork, this
system is ideally suited for applications where input of light is
problematic. A typical application of the attoAFM III microscope is
scanning gate microscopy (SGM) on semiconductor structures. This
microscope is compatible with the commercially available tuning
fork tips, and is available with optional interferometric encoder for
closed loop scanning.
The attoAFM III uses a tuning fork sensor as detection mechanism
for the tip-sample forces, allowing high resolution non-contact
mode imaging without the need for any optical deflection detection
techniques. An AFM tip is glued onto one prong of a small quartz
tuning fork, which is then excited to oscillate in horizontal direc-
tion. The decrease in amplitude due to tip-sample interaction when
approaching the sample is monitored and/or used as a feedback sig-
nal. The force resolution of this technique is typically 0.1 pN.
For more detailed information on the
measurement schematics, please refer to
page 78
10
9
1
2
8
01 LT and HV compatible feedthroughs
3
02 vacuum window
03 microscope insert
7
6
04 superconducting magnet (optional)
05 liquid He dewar (optional)
06 ultra stable Titanium housing
07 xyz coarse positioners
08 xyz scanner
09 quick-exchange sample holder
4
Schematic drawing of the low temperature
attoAFM III and the surrounding liquid
5
helium dewar (optional)
10 tuning fork AFM sensor