Resolution and process window improvement using lift-off

A process for etching a magnetic read head, comprising:

• providing a GMR stack having an topmost layer;
• providing a reticle bearing a pattern that defines two areas, located within a common enclosure, said areas being separated by a narrow region that defines a track width for said read head, with said narrow region being connected at its ends to said common enclosure;
• including in said pattern one or more unconnected line features disposed to lie parallel to said narrow region;
• coating said topmost layer with a first layer of a material that is highly soluble in an etchant and that is patternable through development following selective exposure to radiation;
• coating said first layer with a second layer of a material that is resistant to etching and that is patternable through development, following selective exposure to radiation, thereby forming a bilayer;
• exposing said bilayer to a radiated image of said reticle pattern and then developing said bilayer, whereby a bilayer etch mask is formed on said topmost layer;
• using said etchant, removing part of said first layer thereby undercutting the second layer to a degree sufficient to remove said unconnected line features through lift-off, while leaving said narrow region in place;
• then, leaving said etch mask in place, etching said GMR stack to a depth;
• then depositing, in succession, one or more layers suitable for providing permanent magnetic bias followed by a layer of conductive material;
• and
• then exposing said first layer to said solvent until said second layer is lifted off, including all material thereon.