Large-scale and non-contact surface topography measurement using scanning ion conductance microscopy and sub-aperture stitching technique

Abstract

In this paper, we propose a large-scale and non-contact surface topography measurement method using a non-contact scanning probe microscopy (SPM) technique, scanning ion conductance microscopy (SICM), combined with the sub-aperture stitching technique. The phase correlation techniques were first applied to the three-dimensional (3D) images measured by the SICM to acquire an initially coarse stitching position. Then the tip–tilt compensated sub-aperture stitching algorithm is utilized to eliminate tilts and translations among adjacent images and expand the lateral measuring range of the existing hopping mode SICM system. This SICM and the stitching based method has been used to measure some large-scale samples (micrometer to millimeter scale) in a non-contact, quantitative and high resolution way. Simulation and experimental results on these samples verify the feasibility of this method and the effectiveness of the stitching algorithm. A measuring range of 1.08 mm × 0.55 mm and a lateral resolution of 100 nm or even higher were obtained in these experiments. Compared with atomic force microscopy (AFM), the non-contact feature of the proposed method ensures less damage to the surface topography. The non-optical feature makes the data stitching simpler than the existing optical microscopic methods, which need consider how to compensate the vignetting effect caused by the inhomogeneity of light.

Nanoscale Electrochemical Mapping

“…Typical SICM scans tend to focus on a narrow region of a sample of a few square micrometers, but there have been several recent studies focused on increasing the range of length scales that can be probed with SICM through new approaches to image processing, combining nanoscale precision piezoelectric positioners with shear force actuators, or using micropositioner stages capable of ranges of 10s of millimeters . These approaches increase the range of samples that can be probed and open up exciting new applications for SICM on the macroscale with, for example, whole fingerprints being imaged .…”

Scanning Ion Conductance Microscopy

“…However, increases in the scan scale also increase the cost for SICM and unavoidably reduces resolution because of the decrease of piezo resolution. The Yu group provided an alternate solution for Macro-SICM with a stitching algorithm . Briefly, the large-scale area was divided into a number of small scans that were collected as a series of images.…”

“…The Yu group provided an alternate solution for Macro-SICM with a stitching algorithm. 113 Briefly, the large-scale area was divided into a number of small scans that were collected as a series of images. After collecting the topography information on all the subareas, a stitching algorithm was applied to the image set, in which each image was regarded as a subaperture.…”

Intracellular Electrochemical Sensing

“…SICM is a nanopipette‐based technique that enables imaging of the topography of a target sample . In a typical SICM setup, a single‐barrel nanopipette is filled with an electrolyte solution (PBS, etc.)…”