A landmark-based 3D calibration strategy for SPM

Abstract

We present a new method for the complete three-dimensional (3D) calibration of scanning probe microscopes (SPM) and other high-resolution microscopes, e.g., scanning electron microscopes (SEM) and confocal laser scanning microscopes (CLSM), by applying a 3D micrometre-sized reference structure with the shape of a cascade slope-step pyramid. The 3D reference structure was produced by focused ion beam induced metal deposition. In contrast to pitch featured calibration procedures that require separate lateral and vertical reference standards such as gratings and step height structures, the new method includes the use of landmarks, which are well established in calibration and measurement tasks on a larger scale. However, the landmarks applied to the new 3D reference structures are of sub-micrometre size, the so-called ‘nanomarkers’. The nanomarker coordinates are used for a geometrical calibration of the scanning process of SPM as well as of other instrument types such as SEM and CLSM. For that purpose, a parameter estimation routine involving three scale factors and three coupling factors has been developed that allows lateral and vertical calibration in only one sampling step. With this new calibration strategy, we are able to detect deviations of SPM lateral scaling errors as well as coupling effects causing, e.g., a lateral coordinate shift depending on the measured height position of the probe.

Calibration and verification of areal surface texture measuring instruments

“…A second online list of material measures used for calibrating scanning probe microscopes (SPMs) and optical instruments can be found at www.nanoscale.de/standards.htm. Ritter et al [151] have developed a ''landmark'' material measure to compliment the list of material measures available for the calibration of SPMs [194], and Krü ger-Sehm et al [108] and Fujji et al [46] produce chirped-grating material measures for testing lateral resolution and determining the instrument transfer function (see Sections 7,8 and 9).…”

Design of a sample approach mechanism for a metrological atomic force microscope

“…However, in contrast to most metrological AFMs with a medium measurement range, the metrological AFM developed at KULeuven has an increased Z-range (100 lm instead of 20 lm). This makes the device suitable for three dimensional measurements, which are gaining importance in nanometrology [11]. Also, all components of the presented metrological AFM have a dedicated design in order to achieve high mechanical and thermal stability.…”

Measurement technologies for precision positioning

“…To calibrate 3D measurement volume of e.g. SPM, a 3D micro-pyramid standard has been developed [180].…”