Disk preconditioning apparatus and related method

Abstract

An apparatus and method for preconditioning a magnetic recording disk is provided in which two substantially identical, but opposing, pancake coils are disposed generally parallel to one another with a gap therebetween into which a disk to be preconditioned is inserted. A large pulse of current is delivered to the coils to generate a magnetic field that is sufficiently strong to precondition the disk. The radial fields of each respective pancake coil add together in the gap where the disk is located, and the field presets both the data layer and the hard bias layer of the SUL. Outside of the gap region, the fields cancel one another such that there are essentially no perpendicular fields due to the symmetry of the coils, such that there is very little net residual perpendicular magnetization when the disk is removed from the gap. An electrical circuit for producing the current pulse is provided. An aluminum support structure provides thermal management and magnetic flux conductivity for the system.

Dependencies are inferred from the claim text.