Method and system for providing a magnetoresistive structure using undercut free mask

A method for defining a magnetoresistive structure from a magnetoresistive stack including a plurality of layers, the method comprising:

• providing a bottom antireflective coating (BARC) layer;
• providing a single layer mask having at least one side, a top, and a base at least as wide as the top, the single layer mask exposing a portion of the magnetoresistive stack and a portion of the BARC layer;
• removing the portion of the BARC layer, a covered portion of the BARC layer remaining;
• removing the portion of the magnetoresistive stack to define the magnetoresistive structure;
• providing an insulating layer, a portion of the insulating layer residing on the at least one side of the single layer mask and the at least one side of the covered portion of the BARC layer;
• providing a capping layer on the insulating layer;
• performing an ion mill at an angle from normal to the top surface, the angle being at least seventy degrees and not more than eighty degrees, the ion mill removing the portion of the insulating layer on the at least one side of the single layer mask and a portion of the capping layer on the at least one side of the insulating layer;
• performing a lift off, the lift off removing the single layer mask;
• removing a remaining portion of the covered portion of the BARC layer, a top of the magnetoresistive structure being exposed;
• and
• performing a touch planarization.