Method of fabricating a magnetoresistive bit from a magnetoresistive stack

A method of fabricating a magnetoresistive bit from a magnetoresistive stack including at least two magnetic regions, an intermediate region positioned between the at least two magnetic regions, and a hard mask region, the method comprising:

• (a) etching through at least a first layer of the hard mask region in a first direction to expose a first set of areas in a second layer of the hard mask region;
• (b) after the etching in step (a), etching through at least the first layer of the hard mask region in a second direction to expose a second set of areas in the second layer of the hard mask region;
• (c) after the etching in step (b), etching through at least the first layer of the hard mask region in the first direction to expose a third set of areas in the second layer of the hard mask region;
• (d) after the etching in step (c), etching through at least the first layer of the hard mask region in the second direction to expose a fourth set of areas in the second layer of the hard mask region;
• and
• (e) after the etching in step (d), etching through at least a portion of the thickness of the magnetoresistive stack through the first set, the second set, the third set, and the fourth set of areas.

A method of fabricating a magnetoresistive bit from a magnetoresistive stack including at least two magnetic regions, an intermediate region positioned between the at least two magnetic regions, and a hard mask region, the method comprising:

• (a) etching through at least a first layer of the hard mask region to form a first set of strips exposing a second layer of the hard mask region;
• (b) after the etching in step (a), etching through at least the first layer of the hard mask region to form a second set of strips exposing the second layer of the hard mask region;
• (c) after the etching in step (b), etching through at least the first layer of the hard mask region to form a third set of strips exposing the second layer of the hard mask region, the third set of strips being substantially equally spaced apart from the first set of strips;
• (d) after the etching in step (c), etching through at least the first layer of the hard mask region to form a fourth set of strips exposing the second layer of the hard mask region, the fourth set of strips being substantially equally spaced apart from the second set of strips;
• and
• (e) after the etching in step (d), etching through at least a portion of the thickness of the magnetoresistive stack through the first set, the second set, the third set, and the fourth set of strips.