摘要:
A glide head calibration technique uses two fly height calibrations on a disk media certifier. The first calibration point uses a spin down on bump technique at a first height, and the second calibration point uses a spin down on disk media roughness at a second lower height. With two height data points, a fly height curve of each glide head is approximated very accurately. Once the fly height curve is derived for each head, any fly height can be dialed-in by the disk media certifier for glide testing. This technique achieves glide fly heights between about 4 nm and 8 nm and does so with improved tolerances.
摘要:
A method is presented for glide testing a disk which tests the glide head fly-height by inducing a collision between the glide head and a disk under test. The glide test system is initially calibrated using calibration disks. The method of the invention periodically tests the calibration without interrupting the production testing by lowering the rotation rate until glide head collides with the rotating disk surface. The rotation rate at which the collision occurs is then compared with the value expected based on knowledge of disk samples and the initial calibration. Parameters for acceptable high and low values are established to detect changes in the glide test system performance to trigger automatic or manual recalibration.
摘要:
An air bearing burnish slider burnishes very small asperities and cleans the loose particles that adhere to the magnetic recording media. The slider applies a controllable contact force to effectively burnish disk asperities or partially attached particles. In addition, the slider cleans the loose particles effectively while flying in a stable fashion. In a low pitch design, diagonal rails push particles away from the disk surface and trailing edge pads contact the disk at lower linear velocities. Rail pads retain loose contamination and debris in their pockets and burnish asperities. Another design provides a milder burnish force and flies in a high pitch configuration. The trailing edge pads provide stable contacts and the rails help in sweeping away debris. In both designs, the contact forces can be controlled by adjusting linear velocities. A step taper at the leading edge provides a pitch-producing lift force.