Tohoku Gakuin University Hi-tech Research Center

Magnetic Force Microscope equipped with electromagnet

“MFM: Magnetic Force Microscopy” is one of the members of SPM (Scanning Probe Microscope), where the tip is coated by the magnetic material. MFM enables to observe both the surface profile and the magnetic profile at a same time through tracing the surface of sample by the magnetized tip. As the magnetized tip works like a fine stick-like magnet, the magnetic interaction arises between tip and surface of sample such as the repulsive force in the case of both with the same magnetic pole or the attractive force in the case of both with the opposite magnetic pole. When scanning of the tip is done while oscillating the cantilever, such a magnetic interaction induces the phase shift in the oscillation of cantilever. The detection of the oscillation enables to derive the magnetic attractive and repulsive forces between tip and surface.

The observation of surface magnetic profile of the magnetic material can be done by such a way. MFM has a high-resolution ability, which enables to observe the magnetic recording bit of hard disk and to study the magnetic domain structure of fine magnetic pattern fabricated by the Electron Beam Lithography. MFM also has facility for the stable measurement against the soft surface of sample, due to measurement of the surface profile with non-contact mode. Finally MFM has ability for the detailed observation of the magnetic domain change under applying the magnetic field.