Granted Patent B1

US 7,522,377 · App. 11/009,753 · Granted Apr 21, 2009

Abstract

Claims (22)

1. A magnetic write head comprising:

a seed layer comprising seed-layer grains having either a face-centered cubic (fcc) crystalline structure with a surface plane substantially oriented in a [111] direction or a hexagonal-close-packed (hcp) crystalline structure with a surface plane substantially oriented in a [0001] direction; and

a magnetic layer on the seed layer, the magnetic layer comprising magnetic-layer grains having a body-centered-cubic (bcc) crystalline structure with a surface plane substantially oriented in a [110] direction, wherein the seed-layer grains have an average in-plane seed-layer grain width and the magnetic-layer grains have an average in-plane magnetic-layer grain width smaller than the average in-plane seed-layer grain width.

2. The magnetic write head of claim 1 , wherein the seed layer is ferromagnetic.

3. The magnetic write head of claim 2 , wherein the seed-layer grains have the fcc crystalline structure and comprise a ferromagnetic nickel-iron alloy.

4. The magnetic write head of claim 2 , wherein the seed-layer grains have the hcp crystalline structure and comprise cobalt.

5. The magnetic write head of claim 2 , wherein the seed layer has a thickness in a range between approximately 10 Angstroms and approximately 40 Angstroms.

6. The magnetic write head of claim 1 , wherein the seed layer is non-magnetic.

7. The magnetic write head of claim 6 , wherein the seed-layer grains have the fcc crystalline structure and comprises a non-magnetic nickel-chromium alloy.

8. The magnetic write head of claim 6 , wherein the seed-layer grains have the hcp crystalline structure and comprise titanium.

9. The magnetic write head of claim 6 , wherein the seed layer has a thickness in a range between approximately 10 Angstroms and approximately 1000 Angstroms.

10. The magnetic write head of claim 1 , wherein the magnetic layer comprises an iron-cobalt alloy.

11. The magnetic write head of claim 10 , wherein the iron-cobalt alloy is doped with nitrogen.

12. The magnetic write head of claim 11 , wherein the iron-cobalt alloy comprises between approximately 0.05 atomic % and 2 atomic % nitrogen.

13. The magnetic write head of claim 1 , wherein the magnetic layer has a thickness in a range between approximately 100 Angstroms and approximately 5000 Angstroms.

14. The magnetic write head of claim 1 , wherein the magnetic layer has a thickness of approximately 2000 Angstroms.

15. The magnetic write head of claim 1 , wherein the seed-layer grains have an average in-plane seed-layer grain width in a range between approximately 50 Angstroms and approximately 500 Angstroms.

16. The magnetic write head of claim 15 , wherein the magnetic layer grains have an average in-plane magnetic-layer grain width in a range between approximately 10 Angstroms and approximately 300 Angstroms.

17. The magnetic write head of claim 1 , wherein the average in-plane seed-layer grain width is between a factor of approximately two and a factor of approximately five larger than the average in-plane magnetic-layer grain width.

18. A magnetic write head comprising:

a seed layer comprising seed-layer grains having either a face-centered cubic (fcc) crystalline structure with a surface plane substantially oriented in a [111] direction or a hexagonal-close-packed (hcp) crystalline structure with a surface plane substantially oriented in a [0001] direction; and

a magnetic layer on the seed layer, the magnetic layer comprising magnetic-layer grains having a body-centered-cubic (bcc) crystalline structure with a surface plane substantially oriented in a [110] direction, wherein the magnetic-layer grains have an in-plane grain orientation distribution which comprises approximately equal proportions of three crystallographic directions oriented approximately 120 degrees from one another.

Assignments (8)