HIGH COERCIVITY MULTIFILM HARD MAGNETIC LAYER FOR MAGNETICALLY STABILIZING A SPIN VALVE SENSOR

摘要

A BILAYER SEEDLAYER IS EMPLOYED BETWEEN A HARD MAGNETIC BIASING LAYER AND A NICKEL OXIDE (NIO) PINNING LAYER OF A BOTTOM SPIN VALVE SENSOR WHEREIN THE BIASING LAYER STABILIZES THE MAGNETIC DOMAINS OF MAGNETIC LAYERS IN THE SPIN VALVE SENSOR. THE BILAYER SEEDLAYER INCLUDES A TANTALUM (TA) LAYER ON THE NICKEL OXIDE (NIO) PINNING LAYER AND A CHROMIUM (CR) LAYER ON THE TANTALUM (TA) LAYER. THE HARD MAGNETIC LAYER IS ON THE CHROMIUM (CR) LAYER. THE HARD MAGNETIC LAYER IS A COBALT (CO) BASED HARD MAGNETIC MATERIAL. IN A PREFERRED EMBODIMENT THE TOTAL THICKNESS OF THE BILAYER SEEDLAYER HAS BEEN REDUCED TO LESS THAN 70 A WITHOUT SACRIFICING THE REQUIRED COERCIVITY OF THE HARD MAGNETIC LAYER FOR WITHSTANDING MAGNETIC INCURSIONS WHICH TEND TO SWITCH THE MAGNETIC SPINS OF THE HARD MAGNETIC LAYER.FIG. 9.