Disc drive with layered write coil

• US 6,654,202 B2
• Filed: 06/13/2001
• Issued: 11/25/2003
• Est. Priority Date: 06/20/2000
• Status: Expired due to Term

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Pust, Ladislav R., Mack, Anthony M., Rea, Christopher J.
• Primary Examiner(s): Whitehead, Jr., Carl
• Assistant Examiner(s): Dolan, Jennifer M
• Application Number:
  US09/880,344
• Publication Number:
  US 20010053044A1
• Time in Patent Office: 895 Days
• Field of Search: 360/123, 360/124, 360/119, 360/125
• US Class Current: 360/123.2
• CPC Class Codes: G11B 5/3103 Structure or manufacture of integrated heads or heads mechanically assembled and electrically connected to a support or housing
• CPC Class Codes: G11B 5/3116 Shaping of layers, poles or gaps for improving the form of the electrical signal transduced, e.g. for shielding, contour effect, equalizing, side flux fringing, cross talk reduction between heads or between heads and information tracks G11B5/3113, G11B5/245 take precedence
• CPC Class Codes: G11B 5/312 for reducing flux leakage between the electrical coil layers and the magnetic cores or poles or between the magnetic cores or poles
• CPC Class Codes: G11B 5/313 Disposition of layers
• CPC Class Codes: G11B 5/3967 Composite structural arrangements of transducers, e.g. inductive write and magnetoresistive read G11B5/3906 takes precedence
• CPC Class Codes: G11B 5/40 Protective measures on heads, e.g. against excessive temperature G11B5/31 takes precedence; protection against wear G11B5/255 ; protective structure of the head: see under structures, e.g. G11B5/3106

Abstract

A disc drive includes a disc and a read/write head accessing the disc. The head includes a thermally conductive substrate and a write coil window surrounded by a shared pole piece thermally coupled to the substrate, a central core, a write pole piece and a write gap. A bottom coil adjacent the shared pole piece has multiple turns that have bottom narrowed regions passing through the window. A top coil adjacent the write pole piece has multiple turns that have top narrowed regions passing through the window. The top turns are fewer in number and flattened relative to the bottom turns.

Claims

1. A read/write head, comprising:

a substrate formed of thermally conductive material;

a write coil window surrounded by a shared pole piece thermally coupled to the substrate, a central core, a write pole piece and a write gap;

a bottom coil adjacent the shared pole piece having a bottom plurality of coil turns that have bottom narrowed turns that pass through the write coil window and that are horizontally narrowed relative to opposite turns of the bottom coil;

a top coil adjacent the write pole piece having a top plurality of coil turns that have top narrowed turns that pass through the write coil window and that are horizontally narrowed relative to opposite turns of the top coil;

the top plurality of coil turns being fewer in number and vertically flattened relative to the bottom plurality of coil turns; and

the top narrowed turns overlying the bottom narrowed turns in the write coil window and the top narrowed turns being vertically flattened relative to the bottom narrowed turns in the write coil window.

2. The read/write head of claim 1 wherein the top plurality of coil turns have top widened turns opposite the top narrowed turns.

3. The read/write head of claim 2 wherein the shared pole is truncated along a line between the central core and the top widened turns.

4. The read/write head of claim 2 wherein a portion of heat generated in the top narrowed turns is conducted through the top widened turns to the substrate.

5. The read/write head of claim 1 wherein the bottom coil and the top coil are embedded in a refractory material that is electrically insulating and thermally conductive.

6. The read/write head of claim 5 wherein the refractory material comprises material selected from the group:

alumina, silicon nitride and diamond-like carbon.

7. The read/write head of claim 1 wherein the top narrowed turns in the write coil window include an inner turn adjacent the central core with a cross-section that is small relative to a cross-section of an outer turn of the top narrowed turns in the write coil window.

8. The read/write head of claim 7 wherein a portion of the heat generated in the inner turn is conducted through the central core to the substrate.

9. The read/write head of claim 1 wherein the write gap includes a nonmagnetic metallic layer.

10. The read/write head of claim 9 wherein the nonmagnetic metallic layer conducts heat from the write pole piece to the shared pole piece.

11. A read/write head, comprising:

a read/write head with a top coil and a bottom coil in a write portion of the head formed on a substrate;

the read/write head accessing a disc;

means for conducting heat from a top coil in the read/write head to a substrate in the read/write head; and

the top coil including top narrowed turns that are horizontally narrowed in a write coil window relative to opposite turns of the top coil and that overlie bottom narrowed turns of the bottom coil, the bottom narrowed turns being horizontally narrowed in the write coil window relative to opposite turns of the bottom coil, and the top narrowed turns being vertically flattened relative to the bottom narrowed turns.

12. A method of manufacturing a read/write head, comprising:

forming a read/write head substrate of thermally conductive material;

surrounding a write coil window in the read/write head with a shared pole piece thermally coupled to the substrate, a central core, a write pole piece and a write gap;

providing a bottom coil adjacent the shared pole piece having a bottom plurality of coil turns that have bottom narrowed turns that are horizontally narrowed relative to opposite turns of the bottom coil and that pass through the write coil window;

providing a top coil adjacent the write pole piece with a top plurality of coil turns that have top narrowed turns that are horizontally narrowed relative to opposite turns of the top coil and that pass through the write coil window;

the top plurality of coil turns being fewer in number and vertically flattened relative to the bottom plurality of coil turns; and

positioning the top narrowed turns to overlie the bottom narrowed turns in the write coil window, and shaping the top narrowed turns to be vertically flattened relative to the bottom narrowed turns in the write coil window.

13. The method of claim 12 and further comprising:

providing the top plurality of coil turns with top widened turns opposite the top narrowed turns.

14. The method of claim 13 further comprising:

truncating the shared pole along a line between the central core and the top widened turns.

15. The method of claim 13 further comprising:

conducting a portion of heat generated in the top narrowed turns through the top widened turns to the substrate.

16. The method of claim 12 further comprising:

embedding the bottom coil and the top coil in a refractory material that is electrically insulating and thermally conductive.

17. The method of claim 16 further comprising:

selecting the refractory material from the group;

alumina, silicon nitride and diamond-like carbon.

18. The method of claim 12 further comprising:

including, in the top narrowed turns in the write coil window, an inner turn adjacent the central core with a cross-section that is small relative to a cross-section of an outer turn of the top narrowed turns in the write coil window.

19. The method of claim 18 further comprising:

conducting a portion of the heat generated in the inner turn through the central core to the substrate.

20. The method of claim 12 further comprising:

including a nonmagnetic metallic layer in the write gap.

21. A magnetic coil assembly, comprising:

a substrate formed of thermally conductive material;

a magnetic core structure surrounding a write coil window, the magnetic core structure including a core portion that is thermally coupled to the substrate;

a bottom coil adjacent the core portion, the bottom coil having a bottom plurality of coil turns that have bottom narrowed turns that are horizontally narrowed relative to opposite turns of the bottom coil and that pass through the write coil window; and

a top coil overlying the bottom coil, the top coil having a top plurality of coil turns that have top narrowed turns that are horizontally narrowed relative to opposite turns of the top coil and that pass through the write coil window;

the top plurality of coil turns being fewer in number and vertically flattened relative to the bottom plurality of coil turns, and the top narrowed turns overlying the bottom narrowed turns in the write coil window and the top narrowed turns being vertically flattened relative to the bottom narrowed turns in the write coil window.

22. The magnetic coil assembly of claim 21 wherein a portion of heat generated in the top narrowed turns is conducted through the opposite turns of the top coil to the substrate.

23. The magnetic coil assembly of claim 21 wherein the bottom coil and the top coil are embedded in a refractory material that is electrically insulating and thermally conductive.

24. The magnetic coil assembly of claim 21 wherein the refractory material comprises material selected from the group:

alumina, silicon nitride and diamond-like carbon.

25. The magnetic coil assembly of claim 21 further comprising a central core, wherein the top narrowed turns in the write coil window include an inner turn adjacent the central core with a cross-section that is small relative to a cross-section of an outer turn of the top narrowed turns in the write coil window.