Magnetic Thickness Mapping System - DiskMapper M3

The DiskMapper M3 is a magnetic thickness mapping system that provides non-contact, non-destructive magnetic characterization of the recording layer of perpendicular magnetic recording (PMR) media. The system measures the uniformity of critical magnetic properties, such as the remanence thickness product (Mrt), the remanence coercivity (Hr), and the remanent nucleation field (Hnr), providing feedback for deposition process control.

Benefits:

  • Patented recording layer Mrt measurement is independent of the soft under layer (SUL), providing unique feedback to control the uniformity of media properties
  • Perpendicular write head with maximum field exceeds current production requirements for the characterization of Mrt, Hr and Hnr
  • Universal read and write heads allow easy conversion between all industry-standard media sizes
  • Non-contact, non-destructive mapping provides feedback to minimize variation of magnetic properties over the disk surface

A process issue observed in production trend chart of track-average Mrt

Observation of disk map localizes the issue to excessive circumferential variation at O.D.

Full remanence curves displayed in engineering mode