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An implementation of drift compensation for imaging at the nanoscale is presented. The method is based on computer vision techniques and hence applicable to any microscope that generates images through a computer interface. The algorithm extracts and matches pairs of feature points from consecutive images to compute and compensate for probe–sample misalignments over time. The protocol also applies selection rules that enable it to withstand significant changes in image contrast. We demonstrate our fully automatic implementation by continuously imaging the same area of a Si(100) surface at the atomic scale with scanning probe microscopy over a period of 25 h at room temperature, showing that the method is robust even under the presence of non-linear drift or spontaneous changes of the probe apex. We apply our method to study the movement of pairs of tin atoms confined within a half-unit cell of the Si(111)-(7 × 7) surface and estimate the energy barrier for their diffusion at room temperature.

A method for the automated extraction of the short-range part of the probe-surface interaction from force spectroscopy curves is presented. Our algorithm consists of two stages: the first stage determines a boundary that separates the region where the short-range interaction is dominantly acting on the probe and a second stage that finds the parameters to fit the interaction over the long-range region. We applied this method to force spectroscopy maps acquired over the Si ( 111 ) - ( 7 × 7 ) surface and found, as a result, a faint pattern on the short-range interaction for one of the probes used in the experiments, which would have probably been obviated using human-supervised fitting strategies.

By means of force spectroscopy measurements performed with the cantilever first and second flexural modes under the frequency modulation detection method, the authors corroborate the validity of the relation between tip-surface interaction force and frequency shift for force spectroscopy acquisition using higher cantilever eigenmodes. They estimate a cantilever effective stiffness for the second eigenmode 73 times larger than the static stiffness. This large effective stiffness enables them to perform force spectroscopy with a cantilever oscillation amplitude (A0) as small as 3.6A. The authors provide experimental evidence that, at such small A0 values, normalized frequency shift curves deviate from a A03∕2 scaling and the signal-to-noise ratio is considerably enhanced.

A method for reproducible site-specific force spectroscopic measurements using frequency modulation atomic force microscopy at room temperature is presented. The stability and reproducibility requirements, fulfilled so far only in cryogenic environment, are provided through the compensation of the thermal drift using the atom-tracking technique. The method has been tested performing spectroscopic measurements on atomic positions of the Si(111)-(7×7) surface with Si tips. The room-temperature results presented here compare in quality to previously reported quantitative force spectroscopic data obtained at cryogenic temperatures.