A silicon metal-oxide-semiconductor field-effect transistor Hall bar for scanning Hall probe microscopy

Akinobu Yamaguchi; Hiromasa Saito; Masayoshi Shimizu; Hideki Miyajima; Satoru Matsumoto; Yoshiharu Nakamura; Atsufumi Hirohata

doi:10.1063/1.2968713

A silicon metal-oxide-semiconductor field-effect transistor Hall bar for scanning Hall probe microscopy

Rev Sci Instrum. 2008 Aug;79(8):083703. doi: 10.1063/1.2968713.

Authors

Akinobu Yamaguchi¹, Hiromasa Saito, Masayoshi Shimizu, Hideki Miyajima, Satoru Matsumoto, Yoshiharu Nakamura, Atsufumi Hirohata

Affiliation

¹ Department of Physics, Faculty of Science and Technology, Keio University, Hiyoshi3-14-1 Kohoku, Yokohama 223-8522, Japan.

PMID: 19044353
DOI: 10.1063/1.2968713

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.