Current-perpendicular-to-the-plane giant magnetoresistance (CPP-GMR) sensor with indium-zinc-oxide (IZO) spacer layer

摘要

A current-perpendicular-to-the-plane giant magnetoresistance (CPP-GMR) sensor has a spacer layer that includes electrically conductive indium-zinc-oxide (IZO), i.e., In₂O₃ plus ZnO where the ZnO is present between 5-30 weight percent. The spacer layer may include a protective sublayer, like a layer of Ag, below the IZO layer to prevent oxidation of the reference layer from the oxygen in the IZO layer. The spacer layer includes a top layer consisting essentially of Zn located above the IZO layer below the free layer. Measurements from a large number of CPP-GMR sensors with spacer layers of Ag(9 Å)/IZO(20 Å)/Zn(8 Å) show ΔR/R values of about 15-17% and acceptable RA values of around 100 mΩ·μm².