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Updated: Jun 27, 2026

Scanning-probe Single-electron Capacitance Spectroscopy
Published on: July 30, 2013
A silicon metal-oxide-semiconductor field-effect transistor Hall bar for scanning Hall probe microscopy
Akinobu Yamaguchi1, Hiromasa Saito, Masayoshi Shimizu
1Department of Physics, Faculty of Science and Technology, Keio University, Hiyoshi3-14-1 Kohoku, Yokohama 223-8522, Japan.
Abstract:
We demonstrate successful operation of a scanning Hall probe microscope with a few micron-size resolution by using a silicon metal-oxide semiconductor field-effect transistor (Si-MOSFET) Hall bar, which is designed to improve not only the mechanical strength but also the temperature stability. The Si-MOSFET micro-Hall probe is cheaper than the current micro-Hall probes and is found to be as sensitive as a micro-Hall probe with GaAs/AlGaAs heterostructure or an epitaxial InSb two-dimensional electron gas. This was used to magnetically image the surface of a Sm(2)Co(17) permanent magnet during the magnetization reversal process as a function of an external magnetic field below 1.5 T. This revealed firm evidence of the presence of the inverse magnetic seed as theoretically predicted earlier. Magnetically pinned centers, with a typical size 80 mum, are observed to persist even under a high magnetic field, clearly indicating the robustness of the Si Hall probe against the field application as well as the repetition of the measurement.
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