Magnetic stack including cooling element

Patent metadata

Field	Value
Publication number	US-9761279-B2
Application number	US-201715468216-A
Country	US
Kind code	B2
Filing date	Mar 24, 2017
Priority date	Jun 30, 2014
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

Various embodiments of a magnetic stack are disclosed. In one or more embodiments, the magnetic stack includes first and second shield layers, and a magnetically responsive lamination disposed between the first and second shield layers. The magnetically responsive lamination can be configured to receive a sense current I S therethrough. The magnetic stack also includes a cooling element disposed between the first and second shield layers and thermally coupled to the magnetically responsive lamination. The cooling element can be configured to receive a bias current I B therethrough. And the cooling element can be configured to cool the magnetically responsive lamination during a read function.

First claim

What is claimed is:

1. A method comprising:
reading a selected data pattern from a storage medium of a storage device using a head of the storage device to provide a data signal;
calculating an instability value of the head based on the data signal; and
applying a bias current I B to a cooling element thermally coupled to the head if the instability value is greater than an instability threshold, wherein the cooling element is disposed between first and second shield layers of the head.

2. The method of claim 1 , wherein reading data from the storage medium comprises providing a sense current I S to the head, wherein I S and I B are independently controllable.

3. The method of claim 1 , wherein calculating the instability value comprises determining a bit error rate of the data signal.

4. The method of claim 1 , wherein calculating the instability value comprises calculating an instability value for each head of the storage device.

5. The method of claim 1 , wherein the instability threshold comprises a standard deviation of a bit error rate of the device.

6. The method of claim 1 , further comprising writing additional data to the storage medium if the instability value of the head is less than or equal to the instability threshold.

7. The method of claim 1 , further comprising decreasing the bias current I B if the instability value is less than the instability threshold.

8. The method of claim 1 , wherein the head further comprises a magnetically responsive lamination disposed between the first and second shield layers and configured to receive a sense current I S therethrough, wherein the cooling element is thermally coupled to the magnetically responsive lamination.

9. The method of claim 8 , wherein the cooling element is disposed between the magnetically responsive lamination and the second shield layer.

10. The method of claim 8 , wherein the cooling element is in contact with the magnetically responsive lamination.

11. The method of claim 8 , wherein the magnetically responsive lamination comprises a ferromagnetic free layer, a synthetic antiferromagnetic (SAF) structure, and a spacer layer positioned between the ferromagnetic free layer and the SAF structure.

12. The method of claim 8 , wherein the head further comprises an antiferromagnetic (AFM) structure disposed between the first shield layer and the magnetically responsive lamination and magnetically coupled to the magnetically responsive lamination.

13. The method of claim 1 , wherein the cooling element comprises a Peltier cooling element.

14. The method of claim 1 , wherein the head further comprises insulating material disposed between the cooling element and an air bearing surface (ABS) of the magnetic stack.

15. The method of claim 1 , wherein the cooling element comprises an array of cooling elements.

16. The method of claim 15 , wherein each cooling element of the array of cooling elements is independently controllable.

17. The method of claim 1 , wherein reading the selected data pattern comprises sensing the data pattern a plurality of senses and averaging the plurality of senses to provide the data signal.

18. The method of claim 1 , wherein reading the selected data pattern comprises reading the selected data pattern between about 1 time per minute to about 100 times per minute to provide the data signal.

Assignees

• Seagate Technology Llc

Inventors

• Deen David
• Singleton Eric
• Ramaswamy Vasudevan
• Patwari Mohammed
• Pokhil Taras
• Yi Jae-Young

Classifications

• G11B20/18

  Error detection or correction; Testing {, e.g. of drop-outs} · CPC title

• G11B5/11

  Shielding of head against electric or magnetic fields · CPC title

• G11B5/09

  Digital recording · CPC title

• G11B5/3912 Primary

  Arrangements in which the active read-out elements are transducing in association with active magnetic shields, e.g. magnetically coupled shields (G11B5/3916 takes precedence) · CPC title

• G11B5/115

  Shielding devices arranged between heads or windings ({G11B5/265} , G11B5/29 take precedence) · CPC title