Abstract: Method of providing a substrate with a patterned metal layer disposed thereon, wherein a patterned metal mask is employed in conjunction with ion milling to form the pattern in the metal layer on the substrate. The metal mask as contemplated herein is made of a metallic masking mterial taken from the group consisting of vanadium, tantalum, titanium, and a titanium-tungsten alloy--vanadium being a preferred material because of its resistance to erosion or etching from ion milling coupled with its relatively fast etch rate in a plasma atmosphere. This method has particular application to magnetic bubble domain technology, wherein successive layers of a magnetically soft material, vanadium, and photoresist are deposited on a magnetic film capable of supporting magnetic bubble domain propagation. The layer of magnetically soft material is typically permalloy, and upon being patterned in a selected configuration, defines a bubble propagation path on the magnetic bubble-supporting film.