Wide write head with thermal asperity detector and method of using the same

• US 6,940,669 B2
• Filed: 06/20/2001
• Issued: 09/06/2005
• Est. Priority Date: 06/20/2000
• Status: Expired due to Fees

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Schaenzer, Mark James, Franzen, Scott Michael
• Primary Examiner(s): Hudspeth, David
• Assistant Examiner(s): Rodriguez, Glenda P.
• Application Number:
  US09/885,383
• Publication Number:
  US 20020044369A1
• Time in Patent Office: 1,539 Days
• Field of Search: 360/66, 360/113, 360/124, 360/75, 360/51, 360/46, 360/42, 360/25, 360/31, 369/70, 714/48, 714/25
• US Class Current: 360/25
• CPC Class Codes: G11B 27/36 Monitoring, i.e. supervising the progress of recording or reproducing for digital recording G11B20/00 and s.gr.; for monitoring, testing or measuring of TV recorders of the type covered by H04N5/76 and subgroups, see H04N17/06

Abstract

A system for detecting thermal asperities and magnetic defects on a disc. The system includes a wide write head and a certification head. The wide write head includes a thermal asperity detector and a write element. A method for detecting thermal asperities and magnetic defects comprising writing a track with the wide write head, reading defects with the certification head, and scanning for thermal asperities with the thermal asperity detector. A burst pattern can be written to the disc upon locating a asperity of defect.

Claims

1. A method of detecting a media defect comprising the steps of:

writing a first data track to the media with a write head including a write element and a thermal asperity detector;

detecting magnetic defects on the first data track with a certification head while the media is moving; and

scanning the first data track for thermal asperities with the thermal asperity detector.

2. The method of claim 1, further including the steps of:

writing a second data track to the media;

detecting magnetic defects on the second data track; and

scanning the second data track for thermal asperities.

3. The method of claim 1, further including the step of:

upon locating a thermal asperity during the step of scanning, writing a burst pattern to the media in a location where a thermal asperity is detected wherein the burst pattern is detectable in further analysis of the media.

4. A method of detecting magnetic and thermal asperities on a media comprising the steps of:

writing a first data stream to a first wide track on the media with a write element located on a write head;

reading the first data stream on a first portion of the first wide track for magnetic defects with a read element located on a certifier head; and

scanning the first wide track for thermal asperities with a thermal asperity detector located on the write head.

5. The method of claim 4, further including the steps of:

writing a second data stream to a second wide track on the media with the write element;

reading the second data stream on a second portion of the second wide track for magnetic defects with the certifier head; and

scanning the second wide track for thermal asperities with the thermal asperity detector.

6. The method of claim 4, further including the step of:

upon locating a thermal asperity during the step of scanning, writing a burst pattern to the media in a location where a thermal asperity is detected wherein the burst pattern is detectable in further analysis of the media.

7. The method of claim 4, further including the step of:

stopping writing of the first data stream on the first wide track while reading the first data stream on a portion of first wide write track.

8. A testing system comprising:

a disc drive having a spindle on which a disc can be mounted and motor for rotating the disc;

a write head including a write element for writing a first data track to a disc, and a thermal asperity detector; and

a certification head for detecting magnetic defects on the first data track;

wherein the thermal asperity detector simultaneously scans the first data track for thermal asperities while the certification head detects for magnetic defects.

9. The testing system of claim 8, wherein the thermal asperity detector is fabricated from magnetic material.

10. The testing system of claim 8, wherein the thermal asperity detector is fabricated from nickel.

11. The testing system of claim 8, wherein the thermal asperity detector is fabricated from a material picked from a group consisting of nickel, beryllium and nickel-iron.

12. The testing system of claim 8, wherein the thermal asperity detector has a width ranging from 10 microns to 100 microns.

13. A testing system for detecting thermal asperities and magnetic defects on a media comprising:

a write head including a write element, the write head located on a first support arm wherein the write element is activated to write a track onto the media during a first period;

a thermal asperity detector, included in the write head, wherein the asperity detector is activated to detect asperities during a second period; and

a read head located on a second support arm wherein the read head is positioned to certify the track written by the write element during the second period.

14. A testing system for detecting thermal asperities and magnetic defects on a media comprising:

a write head including a write element and a thermal asperity detector, the write head located on a first support arm wherein the write element is activated to write a track onto the media during a first period and the asperity detector is activated to detect asperities during a second period; and

a read head located on a second support arm wherein the read head is positioned to certify the track written by the write element during the second period.

15. The testing system of claim 14 wherein the thermal asperity detector is fabricated from a non-magnetic material.

16. The testing system of claim 14 wherein the thermal asperity detector is fabricated from a material picked from a group consisting of nickel, beryllium and nickel-iron.

17. The testing system of claim 14 wherein the thermal asperity detector has a width ranging from about 10 microns to 100 microns.

18. The testing system of claim 14, wherein the thermal asperity detector is fabricated from nickel.

19. The testing system of claim 14, wherein the width of the write head is from about 20 microns to 100 microns.

20. The testing system of claim 17, wherein the width of the write head is about 75 microns.

21. The testing system of claim 14, wherein the write element has a first width and the read element has a second width and a ratio of the first width to the second width is from 2 to 11.