FORMATION OF PATTERNED PERMALLOY LAYER

摘要

PURPOSE:To form a pattern of a permalloy layer with the high accuracy and obtain a gently-sloping side edge by a method wherein the electrolytic etching is performed after a patterned mask is formed on the permalloy layer. CONSTITUTION:A permalloy layer 3 is formed on a non-magnetic substrate 1 and a patterned mask layer 5, made of photoresist, is formed on the layer 3. This substrate body 6 is dipped in an electrolytic solution in a bath 12. A platinum electrode 13 and the permalloy layer 3 of the substrate body 6 are facing each other and the electrolytic etching is performed. When the permalloy layer 3 is composed of Ni-Fe alloy, the electrolytic solution 11 should be a nitric acid solution or a persulfonic acid solution. With this constitution, the unmasked region of the permalloy layer 3 is etched from the surface and a pattern, whose side edge is gently-sloping, can be formed.