  We describe a tip-scan-type high-speed XYZ-nanopositioner designed for
scanning ion conductance microscopy (SICM), with a special care being devoted
to the way of nanopipette holding. The nanopipette probe is mounted in the
center of a hollow piezoactuator, both ends of which are attached to identical
diaphragm flexures, for Z-positioning. This design minimizes the generation of
undesirable mechanical vibrations. Mechanical amplification is used to increase
the XY-travel range of the nanopositioner. The first resonance frequencies of
the nanopositioner are measured as $\sim$100 kHz and $\sim$2.3 kHz for the Z-
and XY-displacements, respectively. The travel ranges are $\sim$6 $\mu$m and
$\sim$34 $\mu$m for Z and XY, respectively. When this nanopositioner is used
for hopping mode imaging of SICM with a $\sim$10-nm radius tip, the vertical
tip velocity can be increased to 400 nm/ms; hence, the one-pixel acquisition
time can be minimized to $\sim$1 ms.
