Contact recording tunnel magnetoresistive sensor with layer of refractory metal

• US 8,988,835 B1
• Filed: 10/14/2013
• Issued: 03/24/2015
• Est. Priority Date: 10/14/2013
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Biskeborn, Robert G., Lo, Calvin S.
• Primary Examiner(s): Miller, Brian
• Application Number:
  US14/053,514
• Publication Number:
  US 20150103446A1
• Time in Patent Office: 526 Days
• Field of Search: 360/324.2, 360/316, 360/121
• US Class Current: 360/324.2
• CPC Class Codes: G11B 5/00826 comprising a plurality of single poles or gaps or groups thereof operative at the same time
• CPC Class Codes: G11B 5/255 comprising means for protection against wear in thin film structures G11B5/3106
• CPC Class Codes: G11B 5/3909 Arrangements using a magnetic tunnel junction

Abstract

Various embodiments relate to an apparatus having a sensor with an active tunnel magnetoresistive region, magnetic shields flanking the tunnel magnetoresistive region, and gaps between the active tunnel magnetoresistive region and the magnetic shields. The active tunnel magnetoresistive region includes a free layer, a tunnel barrier layer and a reference layer. At least one of the gaps includes an electrically conductive layer having a refractory material. Other embodiments relate to an apparatus having a sensor with an active tunnel magnetoresistive region, magnetic shields flanking the tunnel magnetoresistive region, and gaps between the tunnel magnetoresistive region and the magnetic shields. The active tunnel magnetoresistive region includes a free layer, a tunnel barrier layer and a reference layer. At least one of the gaps includes an electrically conductive layer having a modified region at a media facing side thereof, the modified region being at least one of nonconductive and mechanically hardened.

Claims

1. An apparatus, comprising:

an array of sensors sharing a common media-facing surface, each sensor having an active tunnel magnetoresistive region, magnetic shields flanking the tunnel magnetoresistive region, and gaps between the active tunnel magnetoresistive region and the magnetic shields,

wherein the active tunnel magnetoresistive region includes a free layer, a tunnel barrier layer and a reference layer,

wherein at least one of the gaps includes an electrically conductive layer having a refractory material.

2. An apparatus as recited in claim 1, wherein the array of sensors includes at least eight sensors in a single magnetic head.

3. An apparatus as recited in claim 1, wherein no writers are present on the common media-facing surface.

4. An apparatus as recited in claim 1, wherein the refractory material includes a metal selected from a group consisting of tungsten, titanium-tungsten, tungsten carbide, rhodium, ruthenium and iridium, and alloys thereof.

5. An apparatus as recited in claim 1, wherein the sensor is an electronic lapping guide.

6. An apparatus as recited in claim 1, wherein the refractory material is selected from a group consisting of conductive oxide, a conductive nitride and a conductive carbide.

7. An apparatus as recited in claim 1, further comprising a seed layer disposed between the refractory material and a surface underlying the refractory material.

8. An apparatus as recited in claim 1, further comprising a layer of a second refractory material above an upper one of the magnetic shields and/or below a lower one of the magnetic shields.

9. An apparatus as recited in claim 1, wherein each sensor further includes a ferromagnetic layer above an upper one of the shields and/or below a lower one of the shields.

10. An apparatus as recited in claim 1, further comprising:

a drive mechanism for passing a magnetic medium over the sensor; and

a controller electrically coupled to the sensor.

11. An apparatus, comprising:

a sensor having an active tunnel magnetoresistive region, magnetic shields flanking the tunnel magnetoresistive region, and gaps between the tunnel magnetoresistive region and the magnetic shields,

wherein the active tunnel magnetoresistive region includes a free layer, a tunnel barrier layer and a reference layer,

wherein at least one of the gaps includes an electrically conductive layer having a modified region at a media facing side thereof, the modified region being at least one of nonconductive and mechanically hardened.

12. An apparatus, comprising an array of sensors, each of the sensors being as recited in claim 11, the sensors sharing a common media-facing surface.

13. An apparatus as recited in claim 12, wherein no writers are present on the common media-facing surface.

14. An apparatus as recited in claim 13, wherein the modified region is an oxidized portion of the electrically conductive layer.

15. An apparatus as recited in claim 11, wherein the modified region is an oxidized portion of the electrically conductive layer.

16. An apparatus as recited in claim 11, wherein the electrically conductive layer includes aluminum, wherein the modified region includes aluminum oxide.

17. An apparatus as recited in claim 11, further comprising a layer of refractory material above an upper one of the magnetic shields and/or below a lower one of the magnetic shields.

18. An apparatus as recited in claim 17, wherein the refractory material includes a material selected from a group consisting of tungsten, titanium-tungsten, tungsten carbide, rhodium, ruthenium, iridium, a conductive oxide, a conductive nitride, a conductive carbide, and non-annealed sendust.

19. An apparatus as recited in claim 11, further comprising a ferromagnetic layer above an upper one of the magnetic shields and/or below a lower one of the magnetic shields.

20. An apparatus as recited in claim 11, further comprising:

a drive mechanism for passing a magnetic medium over the sensor; and

a controller electrically coupled to the sensor.