Department of Physics and Astronomy: Publications and Other Research
Date of this Version
5-8-2006
Abstract
The study of the small, defined magnetic structures has attracted much attention due to interest in both technology applications and fundamental research in micromagnetism. Microcantilever torque magnetometry (MTM) is a promising new experimental technique for measuring such small magnetic features [1]. One of the challenges of using this technique is to place the sample on the cantilever. In this work, we develop a new process for preparing patterned magnetic film on cantilever and show a primarily result of magnetic interactions in a paired magnetic bar measured by MTM. The process of patterning the magnetic film on the cantilever is following: (a) deposit a multilayer Au (200nm)/Cr (10nm) on cantilever, (b) patterning using a focused ion beam (FIB) milling, (c) magnetic film deposition through a mask, and (d) a lift-off process. Fig. 1 shows an example of the patterned cantilever with 300 dots of 500 nm in diameter using this process.
In order to understand the magnetic interaction between a pair of bars, we prepare a sample as shown in Fig. 2. A 7 μm x 7 μm x 30 nm Ni80Fe20 film was put on the top left corner of the MTM cantilever. The Ni80Fe20 film was then patterned by a FIB workstation into two single 7 μm x 3.5 μm x 30 nm bars by cutting a 50 nm gap in the center of the film [Fig. 2(a)]. After the measurement, the top bar was removed with FIB milling and just left a single 7 μm x 3.5 μm x 30 nm bar on the cantilever [Fig. 2(b)].
Comments
This paper appears in: Magnetics Conference, 2006. INTERMAG 2006. IEEE International. Publication Date: 8-12 May 2006. Pages: 583 - 583. Location: San Diego, CA, USA. Copyright © 2006 IEEE. Used by permission.