OPTIMIZED PROCESS FOR THE FABRICATION OF MESOSCOPIC MAGNETIC-STRUCTURES

We have used the advantage of the high etch selectivity between metals in a wet etching process to develop an optimized technique for engine ering magnetic materials. This method is based on electron beam lithog raphy and optimized pattern transfer by a combination of dry and wet e tching. The technique has been used in fabricating mesoscopic Ni80Fe20 dots and wires with lateral dimensions down to 0.2 mu m. We have used scanning electron microscopy to verify the lateral sizes and edge acu ity of the structures. The magnetic properties were characterized usin g magneto-optic Kerr effect and magnetoresistance measurements. A mark ed increase in the coercive held and the saturation held is seen as th e width of the wire is decreased. The magnetoresistance change (partia l derivative R) is found to increase significantly as the width of the wire is decreased. (C) 1997 American Institute of Physics.