Fabrication of large area nanomagnets

Abstract

We have developed a large area technique for fabricating magnetic nanostructures. This technique is based on deep ultraviolet lithography followed by a lift-off process. A phase shift mask is used to create nanoscale patterns of very high density. By varying the focus and exposure doses we have synthesized multiple patterns using the same mask. Arrays of Ni 80Fe 20 nanostructures of different shapes and sizes were fabricated using this technique. Scanning electron microscopy was used to verify the lateral dimensions and uniformity of the structures. We have used a vibrating sample magnetometer to characterize the magnetic properties of the fabricated structures. We observed a marked increase in both the coercivity and the switching field of the patterned nanomagnets compared with the reference film due to the magnetic shape anisotropy.