A concept for the traceable calibration of magneto-optical indicator film (MOIF) based magnetic field imaging devices is presented and discussed for the example of a commercial MOIF device with a 60 × 45 mm2 sensor. The calibration facilitates a quantitative and fast characterization of magnetic microstructures combining relatively high spatial resolution with large imaging areas. The macroscopic calibration is performed using the homogeneous magnetic stray field of a pre-characterized electromagnet with a large pole shoe diameter of 250 mm. However, this calibration alone cannot yet account for the vectorial and spatially fast decaying stray fields of magnetic microstructures. For that, a forward simulation approach is pursued, based on the temperature-dependent magnetic parameters of the MOIF material as resulting from superconducting quantum interference device magnetometry and ferromagnetic resonance measurements. This is complemented by a transfer function-based approach to correct the impact of the sensor thickness and in-plane stray field components. The validity of the combined calibration and simulation approach is proven by means of a quantitative characterization of a magnetic scale. For the commercial MOIF device a 28.4 µm spatial resolution and 1.18 mT field resolution is achieved. The calibration is validated by a comparison to scanning Hall probe microscopy results. Furthermore, the uncertainty budget is discussed.

The future of consumer electronics depends on the capability to reliably fabricate nanostructures with given physical properties. Therefore, techniques to characterize materials and devices with nanoscale resolution are crucial. Among these is magnetic force microscopy (MFM), which transduces the magnetic force between the sample and a magnetic oscillating probe into a phase shift, enabling the locally resolved study of magnetic field patterns down to 10 nm. Here, the progress done toward making quantitative MFM a common tool in nanocharacterization laboratories is shown. The reliability and ease of use of the calibration method based on a magnetic reference sample, with a calculable stray field, and a deconvolution algorithm is demonstrated. This is achieved by comparing two calibration approaches combined with numerical modeling as a quantitative link: measuring the probe's effect on the voltage signal when scanning above a nanosized graphene Hall sensor, and recording the MFM phase shift signal when the probe scans across magnetic fields produced by metallic microcoils. Furthermore, in the case of the deconvolution algorithm, it is shown how it can be applied using the open‐source software package Gwyddion. The estimated magnetic dipole approximation for the most common probes currently in the market is also reported.

Magnetic force microscopy (MFM), which allows mapping of the magnetic field distribution with nanoscale resolution, is a well‐known tool. However, for the last two decades, calibration was available only to a few labs. Now, after a few years of active research, the calibration protocols have been reviewed and improved, making it available to every laboratory. In article number 1906144, Héctor Corte‐León and co‐workers show the progress done toward making quantitative MFM a common tool in nanocharacterization laboratories.

Abstract. Fabrication, characterization and comparison of gold and graphene micro- and nanoscale Hall sensors for room temperature scanning magnetic field microscopy applications are presented. The Hall sensors with active areas from 5 µm down to 50 nm were fabricated by electron-beam lithography. The calibration of the Hall sensors in an external magnetic field revealed a sensitivity of 3.2 mV A−1 T−1 ± 0.3 % for gold and 1615 V A−1  T−1 ± 0.5 % for graphene at room temperature. The gold sensors were fabricated on silicon nitride cantilever chips suitable for integration into commercial scanning probe microscopes, allowing scanning Hall microscopy (SHM) under ambient conditions and controlled sensor–sample distance. The height-dependent stray field distribution of a magnetic scale was characterized using a 5 µm gold Hall sensor. The uncertainty of the entire Hall-sensor-based scanning and data acquisition process was analyzed, allowing traceably calibrated SHM measurements. The measurement results show good agreement with numerical simulations within the uncertainty budget.

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