The Nanotechnology Research Institute (NRI) of the National Institute of Advanced Industrial Science and Technology (AIST), an independent administrative institution, has succeeded in developing a magnetic force probe microscope (MFM) of world’s finest resolution, in collaboration with SII NanoTechnology, Inc. and Fujitsu Ltd.

The R&D work has been carried out under an entrusted program of the New Energy and Industrial Technology Development Organization (NEDO), “Nanotechnology Program, Synthetic Nano-Function Materials Project” (Project Leader: Dr. Hiroshi Yokoyama, Director, NRI, AIST.

The MFM is a device to visualize magnetic property of ferromagnetic nanostructure by detecting very faint magnetic field leaking out of specimen with a magnetic probe machined to a tip diameter as fine as nanometer order (1nm = 1/1,000,000,000m). The MFM is expected to be widely used for R&D of magnetic storage among instruments to characterize magnetic materials at nanometer resolution, because of relatively easy handling and not so expensive price. Recently, technology to fabricate magnetic structure of nanometer scale has evolved through the application of semiconductor technology, followed by the progress in basic study for understanding the magnetic properties of nanostructure, which was not available up to now. In this way, the MFM will be an indispensable tool in areas of basic research, too.

The research group has been making efforts for improving the MFM performance to meet the need of reading weak magnetic information of a specimen, and developing technology for coating a carbon nanotube mounted on a probe (supplied by Daiken Chemical Industry, Co., Ltd.) for atomic force microscope (AFM) uniformly with ferromagnetic film. With this probe, the group succeeded in observing magnetic structure of nanometer scale. A scanning electron micrograph (SEM) image of the tip of newly manufactured MFM probe is shown in Photo 1.

The MFM probe developed by the joint research group can be made operable by simply mounting on a commercially available scanning probe microscope (supplied by SII NanoTechnology Inc. and AIST) In this way, anybody can readily observe ultra-fine magnetic structure with 10nm resolution, exerting a great impact. The MFM will surely be a useful tool not only in magnetic storage, but also in field of emerging spin electronics.

Photo 1 An SEM image of a newly developed MFM probe. A side of the image is 1μm (= 1/1,000,000m). A thin segment represents a carbon nanotube coated with a magnetic film (diameter about 40nm).