Nano-scale defect mapping on a magnetic disk surface using a contact sensor

Yuki Shimizu, Junguo Xu, Hidekazu Kohira, Masayuki Kurita, Toshiya Shiramatsu, Masaru Furukawa

Research output: Contribution to journalArticlepeer-review

45 Citations (Scopus)


Targeting both higher touchdown sensitivity and highly accurate nanometer-scale defect detection on a disk surface, a thermal-contact sensor, integrated into a magnetic-head slider, was developed. It was experimentally shown that the contact sensor has sensitivity for detecting head-disk contact at each radial position on a disk surface equivalent to that of a conventional acoustic-emission (AE) sensor. It was also shown that a defect-detection method using the thermal-contact sensor is feasible. Defect mapping, in which a slider inspecting the disk at a certain clearance detects small defects on the disk surface, done with this method was better sensitive with measurements with an optical surface analyzer (OSA). Defect mapping on a proto-type glide tester, based on a conventional glide tester, using the thermal-contact sensor was also demonstrated.

Original languageEnglish
Article number6028020
Pages (from-to)3426-3432
Number of pages7
JournalIEEE Transactions on Magnetics
Issue number10
Publication statusPublished - 2011 Oct
Externally publishedYes


  • Contact sensor
  • hard-disk drive
  • head-disk interface
  • tribology

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering


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