Fabrication of magnetic submicron-wire channels for the investigation of magnetization reversal

We have demonstrated a process for fabricating magnetic structures with fea ture sizes ranging from 50 nm to several hundred microns using high-resolut ion electron beam lithography with 50 keV electrons followed by Ti evaporat ion and liftoff. The Ti was used as an etch mask for ion milling and then r emoved by SF6 reactive ion etching. A variety of magnetic fine structures w ere fabricated on (CoNi/Pt)(6) multilayer substrates. In particular, submic ron-wire channels, which connect a number of microscopic squares to a large reservoir area, were obtained. The magnetization reversal processes in sub micron wire channels were studied with a conventional magneto-optical Kerr microscope. We found that the switching field for magnetization and the rev ersal behavior of the connected microscopic squares strongly depend on the channel wire width, thereby providing a way to study domain wall motion in a subwavelength scale with diffraction limited methods. (C) 1998 American V acuum Society. [S0734-211X(98)04206-1].