High speed piezoresponse force microscopy: <1 frame per second nanoscale imaging

Abstract

An atomic force microscopy (AFM) based technique is described for mapping piezoactuation with nanoscale resolution in less than a second per complete image frame. “High speed piezo force microscopy” (HSPFM) achieves this >100× increase in acquisition rates by coupling a commercial AFM with concepts of acoustics. This allows previously inaccessible dynamic studies, including measuring ferroelectric domain nucleation and growth during in situ poling. Hundreds of consecutive images are analyzed with 49 μs temporal resolution per pixel per frame, revealing 32 nucleation sites/μm2 with 36 μm/s average domain velocities. HSPFM images acquired in as fast as 1/10th s are also presented.

Ferroelectric or non-ferroelectric: Why so many materials exhibit “ferroelectricity” on the nanoscale

“…These frequency behaviors were explored by a number of authors. 95,[182][183][184] At low frequencies the frequency dispersion of the transfer function is relatively small and is primarily associated with the non-idealities of the cantilever design. Practically, variations of 10-20% (or more) are common, allowing establishing piezoelectric properties within this order of magnitude.…”

“…Furthermore, mathematical analysis of the data under some general assumptions of the peak shape allows extraction of Q-factor. Finally, the fast lock-in sweep approach by Hurley 193,194 and rapid imaging by Huey 183,184 at sequential frequencies should be mentioned in this context. In all these cases, the electromechanical response and local resonance frequency can be determined simultaneously.…”

High-speed atomic force microscopy for materials science

“…A lock in amplifier measures the phase of the probes mechanical response to the AC electrical signal. Nath et al 223 use the phase to map the domain orientation sample directly under the tip with a lateral resolution of 5 nm. A 'stroboscopic technique' was used to allow the domain orientation flipping to be recorded at each pixel with 49 μs temporal resolution.…”

High-Resolution Studies of Domain Switching Behavior in Nanostructured Ferroelectric Polymers

“…31 In the former case, the electrically biased tip is scanned over a selected area in the range from several to tens of square micrometers. 26,32 Provided that a tip-generated field exceeds the local threshold field, polarization reversal in the scanned area can be achieved. The efficacy of this type of polarization control in the individual PVDF-TrFE nanomesas is illustrated in Figures 2a−c and 3a−c.…”