A Scanning Hall Probe Microscope for high resolution, large area, variable height Magnetic Field Imaging

TL;DR

This paper introduces a versatile scanning Hall probe microscope capable of high-resolution, large-area magnetic field imaging at variable heights, suitable for micro-magnet array studies in ambient conditions.

Contribution

It presents a novel microscope design integrating sample positioning and scanning with a large scan range and sub-micron resolution, including new Hall probes and a probe-sample distance regulation method.

Findings

Achieved a scan resolution of 0.1 μm.

Demonstrated probe-sample distances below 2 μm.

Enabled local B(z) profile recording.

Abstract

We present a Scanning Hall Probe Microscope operating in ambient conditions. One of the unique features of this microscope is the use of the same stepper motors for both sample positioning as well as scanning, which makes it possible to have a large scan range (few mm) in x and y directions, with a scan resolution of 0.1 $\mu$m. Protocols have been implemented to enable scanning at different heights from the sample surface. The z range is 35 mm. Microstructured Hall probes of size 1-5 $\mu$m have been developed. A minimum probe-sample distance \textless{} 2 $\mu$m has been obtained by the combination of new Hall probes and probe-sample distance regulation using a tuning fork based force detection technique. The system is also capable of recording local B(z) profiles. We discuss the application of the microscope for the study of micro-magnet arrays being developed for applications in micro-systems. * gorky.shaw@ulg.ac.be.; Present address: