Shape enhanced pin read head magnetic transducer with stripe height defined first and method of making same

• US 8,836,059 B2
• Filed: 12/21/2012
• Issued: 09/16/2014
• Est. Priority Date: 12/21/2012
• Status: Active Grant

• Current Assignee: JP Morgan Chase Bank, N.A. (JP Morgan Chase & Co)
• Original Assignee: HGST Netherlands B.V. (Western Digital Corporation)
• Inventors: Ahn, Yongchul, Dang, Xiaozhong, Hsu, Yimin, Le, Quang, Liao, Simon, Liu, Guangli, Pentek, Aron, Leong, Thomas
• Primary Examiner(s): HO, TU TU V
• Application Number:
  US13/724,662
• Publication Number:
  US 20140175576A1
• Time in Patent Office: 634 Days
• Field of Search: 257/421, 257/422, 438/48, 360/324.12
• US Class Current: 257/421
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: G11B 2005/3996 large or giant magnetoresistive effects [GMR], e.g. as generated in spin-valve [SV] devices
• CPC Class Codes: G11B 5/3909 Arrangements using a magnetic tunnel junction
• CPC Class Codes: G11B 5/3932 Magnetic biasing films
• CPC Class Codes: H01L 21/02104 Forming layers deposition in general C23C; crystal growth in general C30B
• CPC Class Codes: H01L 29/82 controllable by variation of the magnetic field applied to the device

Abstract

The present invention generally relates to a magnetic sensor in a read head having a hard or soft bias layer that is uniform in thickness within the sensor stack. The method of making such sensor is also disclosed. The free layer stripe height is first defined, followed by defining the track width, and lastly the pinned layer stripe height is defined. The pinned layer and the hard or soft bias layer are defined in the same process step. This approach eliminates a partial hard or soft bias layer and reduces potential instability issues.

Claims

1. A magnetic head, comprising:

a sensor stack formed over a substrate, the sensor stack having a pinned layer, a free layer and a non-magnetic layer sandwiched between the pinned layer and the free layer;

a first hard or soft bias layer disposed within a first channel, positioned within the sensor stack and having a substantially uniform thickness, wherein the first channel is defined by a first barrier layer and bound by the free layer, the non-magnetic layer, the pinned layer and the substrate;

a second hard or soft bias layer disposed within a second channel, positioned within the sensor stack and having a substantially uniform thickness, wherein the second channel is defined by a second barrier layer and bound by the free layer, the non-magnetic layer, the pinned layer and the substrate;

a first dielectric layer bordered by and in contact with the first barrier layer, the pinned layer and the first hard or soft bias layer; and

a second dielectric layer bordered by and in contact with the second barrier layer, the pinned layer and the second hard or soft bias layer.

2. The magnetic head of claim 1, wherein the non-magnetic layer comprises MgO for tunnel junction magnetoresistive (TMR) barrier or AgSn for current perpendicular to the plane (CPP) spacer.

3. The magnetic head of claim 2, wherein the first barrier layer is disposed within the first channel on the substrate, wherein the first hard or soft bias layer is disposed on the first barrier layer.

4. The magnetic head of claim 3, wherein the first barrier layer comprises SiN, TaOx, AlOx, or SiOxNy, the first hard bias layer comprises CoFe, CoPt, FePt, or CoPtCr, and the first soft bias layer comprises NiFe, CoFe, NiFeMo, alloys of these compounds, or any combination thereof.

5. The magnetic head of claim 4, wherein the second barrier layer is disposed within the second channel on the substrate, wherein the second hard or soft bias layer is disposed on the second barrier layer.

6. The magnetic head of claim 5, wherein the second barrier layer comprises SiN, TaOx, AlOx, or SiOxNy, the second hard bias layer comprises CoFe, CoPt, FePt, or CoPtCr, and the second soft bias layer comprises NiFe, CoFe, NiFeMo, alloys of these compounds, or any combination thereof.