A study of focused ion beam patterned thin magnetic films with soft x-ray and magneto-optical microscopy

Cook, P

Abstract

Until the last few years, focussed ion beam systems were primarily used within the
semiconductor industry as tools for modifying prototype integrated circuits, but owing to the
development of commercial systems and the concomitant reduction in costs, they are rapidly
becoming more popular within academic institutions for research purposes. This work
investigates the potential application of the focussed ion beam to the study of patterned
magnetic media, which is an area of increasing interest as new methods of extending the
performance limits of current magnetic storage media are sought. The effects of quasihomogeneous
Ga ion implantation and micro-machining on the structural properties and
magnetic behaviour of thin Fe films have been studied by various microscopy techniques.
Doses on the order of 8 X 10 15 ions cm"2 were found to induce structural changes in the
polycrystalline microstructure, but the ferromagnetic properties were found to be reasonably
resistant to ion implantation. The formation of magnetic domains within patterned arrays of
simple geometric shapes was studied using magnetic transmission X-ray microscopy and Xray
magnetic circular dichroism. Hysteresis properties of the patterns were determined by
magneto-optical measurements using a specially designed dual photoelastic modulator-based
polarimeter. A detailed description of the polarimeter is given along with a new calibration
method, which improved the accuracy of the measurement system in comparison to a more
conventional approach.

Citation

Cook, P. A study of focused ion beam patterned thin magnetic films with soft x-ray and magneto-optical microscopy. (Thesis). Salford : University of Salford

• Thesis Type: Thesis
• Deposit Date: Oct 3, 2012
• Publicly Available Date: Oct 3, 2012
• Award Date: Jan 1, 2010