Fast scanning, new achievements: High quality noncontact measurements of HOPG with scan rates up to 70 Hz

AIST-NT presents the new achievement in fast scanning technology using the combination of SmartSPM™ scanner, NanoWorld ArrowTM UHF (ultra high frequency) silicon probe and AIST-NT’s MagicScan™ technology.
Measurements conditions: Sample – HOPG; 8x8 microns area; 512х512 points; Probe - NanoWorld ArrowTM UHF silicon probe, resonant frequency 1.1 MHz Mode - AC-noncontact; cantilever oscillation amplitude - 8nm.
Scan rate changes step-by-step from 10Hz to 60Hz during the scanning process. The real scan rate is shown at the left-bottom corner.
1. High speed scanning in Non-Contact AFM Mode. Non-contact mode with small amplitude of cantilever oscillations prevents from damaging the sample and/or the tip. (“Non-contact” means that the tip and the surface are mostly in light attractive interaction opposite to the “semicontact” and “contact” mode, when the tip and the surface are mostly or permanently in strong repulsive interaction).
Scan rate 30Hz.
2. No image distortions at scan rates as high as 50Hz. Any marked distortions of image due to fast scanner speed become significant after the scan rates exceed 40-50 Hz. Those distortions are mainly smoothing of HOPG multiple-atomic steps. You can better estimate distortions during the scan rate increase by watching the corresponding cross sections.
Scan rate 50Hz.
3. Image stability with changing scan rates. Almost no image shift is observed as a result of the increase of the scan speed in a wide range of scan rates. In most modern AFMs increasing the scan rate (with XY closed loop operation) results in significant shifts of the image due to the increase of the feedback error in fast direction with the increase of the scanning speed. We overcome this drawback by implementing the advanced measurement synchronization technique.
Scan rate 70Hz.