Sensor structure having increased thermal stability

Patent metadata

Field	Value
Publication number	US-9454978-B2
Application number	US-201514884527-A
Country	US
Kind code	B2
Filing date	Oct 15, 2015
Priority date	Oct 27, 2014
Publication date	Sep 27, 2016
Grant date	Sep 27, 2016

Abstract

A reader sensor having a dusting layer having a thickness less than 5 Angstroms between and in contact with the AFM layer and with the pinned layer. The dusting layer comprises a non-magnetic, electrically conducting material, such as ruthenium or iridium. The reader sensor has a free layer composed of a material free of nickel (Ni).

First claim

What is claimed is:

1. A method comprising:
providing a sensor stack having a non-continuous dusting layer between and in contact with but not magnetically coupled to an antiferromagnetic (AFM) layer and a pinned layer, and a free layer composed of a material free of nickel, the dusting layer having a thickness less than 5 Angstroms and comprising a non-magnetic electrically conducting material; and
annealing the sensor stack at a temperature of 325° C. to 400° C.

2. The method of claim 1 wherein the dusting layer of the sensor stack comprises at least one of Ru or Ir.

3. The method of claim 1 , wherein the free layer of the sensor stack comprises CoFeTa, CoFeB, or CoTa.

4. The method of claim 1 , wherein the AFM layer has a thickness of 40 Angstroms or less.

5. A method comprising:
providing a reader sensor stack having an antiferromagnetic (AFM) layer having a thickness of 40 Angstroms or less, a pinned layer, a non-magnetic electrically conducting, non-continuous dusting layer having a thickness no greater than 5 Angstroms between and in contact with the AFM layer and the pinned layer, and a free layer composed of a material free of nickel; and
annealing the sensor stack at a temperature of 325° C. to 400° C.

6. The method of claim 5 wherein the thickness of the dusting layer is in the range of 1 to 3 Angstroms.

7. The method of claim 5 wherein the dusting layer comprises at least one of Ru or Ir.

8. The method of claim 5 , wherein the free layer comprises CoFeTa, CoFeB, or CoTa.

9. A method comprising:
providing a reader sensor structure comprising an antiferromagnetic (AFM) layer comprising manganese (Mn), a pinned layer, a non-magnetic, electrically conducting dusting layer consisting of one of ruthenium (Ru) or iridium (Ir) and having a thickness no greater than 5 Angstroms with pinholes therethrough, the dusting layer between and in contact with both the AFM layer and the pinned layer, and a nickel-free (Ni-free) free layer; and
annealing the sensor stack at a temperature of 325° C. to 400° C.

10. The method of claim 9 wherein the free layer comprises CoFe, CoFeB, or CoFeX, where X is a refractory material.

11. The method of claim 10 wherein the free layer comprises CoFeX and the refractory material is tantalum (Ta), niobium (Nb), hafnium (Hf), or zirconium (Zr).

12. The method of claim 10 , wherein the free layer comprises multiple layers.

13. The method of claim 9 , wherein the AFM layer has a thickness of 40 Angstroms or less.

Assignees

• Seagate Technology Llc
• Seagate Technology Llc

Inventors

• Nikolaev Konstantin
• Pokhil Taras
• Stankiewicz Andrzej
• Patwari Mohammed
• Singleton Eric

Classifications

• G11B2005/3996

  large or giant magnetoresistive effects [GMR], e.g. as generated in spin-valve [SV] devices · CPC title

• H01L43/08

  Electricity · mapped topic

• G11B5/3906 Primary

  Details related to the use of magnetic thin film layers or to their effects · CPC title

• G11B5/3912

  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

• Y10T29/49034

  Treating to affect magnetic properties · CPC title