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In recent years, there has been growth in the development of high-speed AFMs, which offer the possibility of video rate scanning and long-range scanning over several hundred micrometres. However, until recently these instruments have been lacking full traceable metrology. In this paper traceable metrology, using optical interferometry, has been added to an open-loop contact-mode high-speed AFM to provide traceability both for short-range video rate images and large-area scans made using a combination of a high-speed dual-axis scanner and long-range positioning system. Using optical interferometry to determine stages’ positions and cantilever displacement enables the direct formation of images, obviating the need for complex post-processing corrections to compensate for lateral stage error. The application of metrology increases the spatial accuracy and linearisation of the high-speed AFM measurements, enabling the generation of very large traceable composite images.

Non-raster scanning is being widely used to increase the scanning speed of atomic force microscopes (AFMs). However, like any other AFM scanning techniques, non-raster scanning can also suffer from drift during the scanning process. This paper presents a simple novel method based on cross-correlation for the effective drift correction of non-raster Lissajous AFM scans with intersecting paths. The drift in x, y and z axes can be determined using the crossing points and repeated scans of the same features. In this paper, the general method is presented together with experimental results using Lissajous scans of two artifacts, which demonstrate that the drift in the three axes and the additional tilt can all be corrected resulting in significant improvement in the image obtained. Our drift correction method can overcome the limitations of the existing AFM drift correction methods which are usually based on extra scanning, and it exploits the crossing scan paths and four scanning cycles inherent in Lissajous scanning without using additional scans to effectively determine the three-dimensional drift using cross-correlation and least squares techniques. The drift correction method can be used with any AFMs capable of Lissajous scanning.

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