Real-space post-processing correction of thermal drift and piezoelectric actuator nonlinearities in scanning tunneling microscope images

Abstract

We have developed a real-space method to correct distortion due to thermal drift and piezoelectric actuator nonlinearities on scanning tunneling microscope images using Matlab. The method uses the known structures typically present in high-resolution atomic and molecularly-resolved images as an internal standard. Each image feature (atom or molecule) is first identified in the image. The locations of each feature's nearest neighbors (NNs) are used to measure the local distortion at that location. The local distortion map across the image is simultaneously fit to our distortion model, which includes thermal drift in addition to piezoelectric actuator hysteresis and creep. The image coordinates of the features and image pixels are corrected using an inverse transform from the distortion model. We call this technique the thermal-drift, hysteresis, and creep transform (DHCT).Performing the correction in real space allows defects, domain boundaries, and step edges to be excluded with a spatial mask. Additional real-space image analyses are now possible with these corrected images. Using graphite(0001) as model system, we show lattice fitting to the corrected image, averaged unit cell images, and symmetry-averaged unit cell images.Statistical analysis of the distribution of the image features around their best-fit lattice sites measures the aggregate noise in the image, which can be expressed as feature confidence ellipsoids.

Extraction of Hidden Science from Nanoscale Images

“…By recording the tip height at every scanned pixel, an STM topographic image can be reconstructed. The most common scan pattern is to raster the tip across the surface in a line-by-line fashion (Figure a) . For the first STM image, analog traces of piezoelectric locations were recorded by a chart recorder.…”

Robust, Fiducial-Free Drift Correction for Super-resolution Imaging

“…Drift occurs in all varieties of microscopy, for example, scanning electron microscopy (SEM) 1,6 , scanning (electron) tunneling microscopy (STM) 7,8 , and scanning probe microscopy 9 among others. Here, we are concerned with super-resolution microscopy of blinking fluorescent particles in which the images are taken over many movie frames [10][11][12][13] .…”

“…Some researchers have suggested tracking image features, for example, the center of mass of a cell-like object 17 . Several techniques involve identifying and extracting image features, then matching them for global correspondence 6 , using clusters of those features 2 , or their nearest (feature) neighbors 8 in order to deduce the drift. These techniques work best with non-pointlike features 6 .…”

Opportunities in the Synthesis and Design of Radioactive Thin Films and Nanoparticles

“…This type of deposition is the norm in surface science, where any molecule with an appropriate vapor pressure can be leaked into an ultrahigh-vacuum chamber at a certain pressure and duration, allowing for well-defined surface coverages to be achieved. There are also some conditions where atmospheric pressures and gas compositions can be used, such as in the production of self-assembled monolayers of alkanethiols on gold . Like the drop-casting approach, ambient vapor deposition can be used for molecule–substrate combinations that form chemical bonds within reasonable time scales.…”

“…There are also some conditions where atmospheric pressures and gas compositions can be used, such as in the production of selfassembled monolayers of alkanethiols on gold. 70 Like the dropcasting approach, ambient vapor deposition can be used for molecule−substrate combinations that form chemical bonds within reasonable time scales.…”