Magnetoresistive stack/structure and method of manufacturing same

A method of manufacturing a magnetoresistive stack/structure from:

• (i) a first magnetic region including one or more layers of magnetic material, (ii) a dielectric layer disposed over the first magnetic region, (iii) a second magnetic region including one or more layers of magnetic material, wherein the second magnetic region is disposed over the dielectric layer, the method comprising:
• etching through the second magnetic region to (i) provide sidewalls of the second magnetic region and (ii) expose a surface of the dielectric layer;
• depositing a first encapsulation layer on the sidewalls of the second magnetic region and on re-deposited material that is disposed on portions of the exposed surface of the dielectric layer, wherein the re-deposited material includes one or more magnetic materials of the second magnetic region;
• etching (i) the first encapsulation layer which is disposed over the exposed surface of the dielectric layer using a first etch process and (ii) the re-deposited material disposed on the surface of the dielectric layer using a second etch process, wherein, after etching the first encapsulation layer and the re-deposited material, a portion of the first encapsulation layer remains on the sidewalls of the second magnetic region;
• depositing a second encapsulation layer:
• (i) on the first encapsulation layer which is disposed on the sidewalls of the second magnetic region and (ii) over the exposed surface of the dielectric layer;
• etching (i) the second encapsulation layer which is disposed over the exposed surface of the dielectric layer and (ii) through the exposed surface of dielectric layer to form a tunnel barrier and provide sidewalls thereof;
• and
• etching the first magnetic region to provide sidewalls thereof after etching through the exposed surface of dielectric layer.