AIST-NT
presents the MagicScan technology which is the set of feedback and scanning
process control algorithms. These algorithms allow eliminating different dynamical
errors such as overshooting, ringing and phase lag.
The MagicScan key feature is the absence or some negligible level of image
distortions while the scan rate is altered over the wide range.
When the MagicScan technology is applied together with the SmartSPM™
scanner, the outstanding results can be achieved because our SmartSPM™
scanner owns the highest XY and Z resonant frequencies among all commercially
available SPM wide range scanners (100×100x15 um, up to 7kHz in XY &
15kHz in Z).
To demonstrate our new technology, we have chosen a sample with some complex
topography. The sample is a silicon test grating with 3 microns pitch and 25
nm height. The imaging of such samples is a hard job for any SPM. First, it’s
due to several or many (on scan areas of tens of microns) sharp steps along
scan line. Second, the surface is rather smooth that makes it possible to clearly
see any ringing and overshooting of the scanner. In addition, the imaging of
small steps (few nanometers) among the high steps (25 nm) shows no loss of resolution
while accelerating the scan rate.
We use the semicontact AFM mode with a stiff probe (i.e. resonance frequency
is about 500 kHz), 12?12 microns and 30?30 scan areas and 300×300 and
400?400 points XY image resolution respectively.
On the 12×12 microns scan area the rate is increased from 3 to 30 lines
per second, while on the 30×30 microns area it’s increased from
2 to 20 lines/sec. The actual value of the current scan rate is shown near the
“rate ” field in the scan window (since we use the Z-error adaptive
scanning algorithm, the actual rate is slightly different from the setting value).
On the bottom-right corner you can see the scanner X-sensor signal, which corresponds
to the scanner movement. The frequency of this signal is equal to the scan rate.
12um scanning
30um scanning