Fabrication of a nano-magnet on a piezo-driven tip in a TEM sample holder

A nanometer-sized magnet (nano-magnet) was fabricated on the tip of a tungsten needle by electron-beam-induced deposition with Fe(CO)₅ gas. The needle tip, which can be moved with a stepping motor and piezo-driver, was attached inside a specially designed TEM specimen holder. This nano-magnet on the piezo-driven tip is capable of making an approach to magnetic nanostructures formed on a substrate so that the nanometer-scale magnetic interaction could be studied. Electron holography observation of the magnetic field around the nano-magnet showed that the residual magnetic flux density B_r of the nano-magnet was about 0.48T.