Head–Disk Interfacial Behavior in Glide Tests for Manufacturing Hard Disks

Abstract

This study was carried out to investigate the interfacial behavior of a glide head and a bump disk during the glide head calibration for glide tests. The glide test combined with a burnishing process is widely employed by the hard disk industry to test the smoothness of a disk surface. The bump avalanche test using a calibrated glide head and a bump disk results in the bump avalanche curve that graphically shows how the glide test system reacts with the precharacterized asperities (bumps). Experiments were performed to discover the fact that the avalanche point is affected by the Z-height and the tilting angle of the laser bumps on bump disks.

Resolving the Extra Dimensions for Gravity

“…[29] "To obtain accurate glide test results, many calibration methods and bump disks are designed." [Zhong & Zheng, 2003][31] [35][36][37][38][39][40][41] Following the fabrication, the disk was placed on the spindle of a Phase Metrics MG250 certifier and magnetically erased using a wide-track MIG inductive head. The disk was then scanned using a 50% slider with a piezoelectric crystal mounted on the side of one of the sliders (i.e., a Piezo Glide or Glide head), spun at a constant linear velocity of 890 inches per second (ips)(~24.9 m/s), and measured for the mechanical force signal from the piezoelectric glide head.…”

Resolving the extra dimensions for gravity

“…"To obtain accurate glide test results, many calibration methods and bump disks are designed." (Zhong & Zheng, 2003)[31] [35][36][37][38][39][40][41] Following fabrication, the disk was placed on the spindle of a Phase Metrics MG250 certifier and magnetically erased using a wide track MIG inductive head. The disk was then scanned using a 50% slider with a piezoelectric crystal mounted on the side of one of the sliders (i.e., a Piezo Glide or Glide head) and the disk was spinning at a constant linear velocity of 890 inches per second (ips) and was measured for mechanical force signal from the piezoelectric Glide head.…”