Shield designed for middle shields in a multiple sensor array
View Patent ↗A method and system provide a magnetic transducer having an air-bearing surface (ABS) and including first and second read sensors and a shield. The shield is in a down track direction from the first read sensor and between the first and second read sensors. The shield includes a first shield layer, a second shield layer and an insulating layer between the first and second shield layers. The first shield layer is between the first read sensor and the second shield layer. The second shield layer is between the first shield layer and the second read sensor. The first shield layer has a first footprint. The second shield layer has a second footprint. The second shield layer overlaps the first shield layer in the down track direction. The overlap is not more than fifty percent of the first footprint and not more than fifty percent of the second footprint.
1. A magnetic read transducer having an air-bearing surface (ABS) and comprising:
a first read sensor;
a shield residing in a down track direction from the first read sensor, the shield including a first shield layer, a second shield layer and an insulating layer between the first shield layer and the second shield layer, the first shield layer residing between the first read sensor and the second shield layer, the first shield layer having a first footprint, the second shield layer having a second footprint, the second shield layer overlapping the first shield layer in the down track direction by an overlap, the overlap being not more than fifty percent of the first footprint and not more than fifty percent of the second footprint; and
a second read sensor, the first shield layer residing between the first read sensor and the second read sensor in the down track direction, the second shield layer being between the first shield layer and the second read sensor.
2. The magnetic read transducer of claim 1 further comprising:
a first read shield; and
a second read shield, the first read sensor, the second read sensor and the shield residing between the first read shield and the second read shield.
3. The magnetic read transducer of claim 1 wherein the overlap is not more than twenty-five percent of the first footprint and not more than twenty-five percent of the second footprint.
4. The magnetic read transducer of claim 1 wherein the overlap is not more than twenty percent of the first footprint and not more than twenty percent of the second footprint.
5. The magnetic read transducer of claim 1 wherein the overlap is not more than fifteen percent of the first footprint and not more than fifteen percent of the second footprint.
6. The magnetic read transducer of claim 1 wherein the first shield layer is substantially a mirror image of the second shield layer such that the shield is substantially symmetric with respect to a location of the second read sensor in a cross track direction.
7. The magnetic read transducer of claim 1 wherein the second read sensor has a first side and a second side opposite to the first side in a cross-track direction and wherein the first shield layer extends further from the first side in the cross-track direction than from the second side and wherein the second shield layer extends further from the second side in the cross-track direction than from the first side.
8. The magnetic read transducer of claim 1 wherein the overlap has a first distance along the ABS and a second distance perpendicular to the ABS, the first distance being greater than the second distance.
9. The magnetic read transducer of claim 1 wherein the insulating layer has a dielectric constant less than a silicon dioxide dielectric constant.
10. The magnetic read transducer of claim 9 wherein insulating layer includes at least one of SiO and SiOC.
11. The magnetic read transducer of claim 1 wherein the insulating layer has a first thickness within a first distance of the first and second read sensors and a second thickness more than a second distance from the first read sensor and second read sensor, the first thickness being less than the second thickness.
12. The magnetic read transducer of claim 11 wherein the first distance is five microns.
13. The magnetic read transducer of claim 11 wherein the first thickness is at least ten nanometers and wherein the second thickness is at least twenty nanometers.
14. A disk drive comprising:
a media;
a slider including a magnetic read transducer having an air-bearing surface (ABS), the magnetic read transducer including a first read sensor, a shield, and a second read sensor, the shield including a first shield layer, a second shield layer and an insulating layer between the first shield layer and the second shield layer, the first shield layer residing between the first read sensor and the second shield layer, the first shield layer having a first footprint, the second shield layer having a second footprint, the second shield layer overlapping the first shield layer in the down track direction by an overlap, the overlap being not more than fifty percent of the first footprint and not more than fifty percent of the second footprint, the second shield layer being between the first shield layer and the second read sensor.
15. A method for providing a magnetic read transducer having an air-bearing surface (ABS), the method comprising:
providing a first read sensor;
providing a shield residing in a down track direction from the first read sensor, the shield including a first shield layer, a second shield layer and an insulating layer between the first shield layer and the second shield layer, the first shield layer residing between the first read sensor and the second shield layer, the first shield layer having a first footprint, the second shield layer having a second footprint, the second shield layer overlapping the first shield layer in the down track direction by an overlap, the overlap being not more than fifty percent of the first footprint and not more than fifty percent of the second footprint; and
providing a second read sensor, the first shield layer residing between the first read sensor and the second read sensor in the down track direction, the second shield layer being between the first shield layer and the second read sensor.
16. The method of claim 15 further comprising:
providing a first read shield; and
providing a second read shield, the first read sensor, the second read sensor and the shield residing between the first read shield and the second read shield.
17. The method of claim 15 wherein the overlap is not more than twenty-five percent of the first footprint and not more than twenty-five percent of the second footprint.
18. The method of claim 15 wherein the overlap is not more than twenty percent of the first footprint and not more than twenty percent of the second footprint.
19. The method of claim 15 wherein the overlap is not more than fifteen percent of the first footprint and not more than fifteen percent of the second footprint.
20. The method of claim 15 wherein the first shield layer is a mirror image of the second shield layer such that the shield is substantially symmetric with respect to a location of the second read sensor in a cross track direction.
21. The method of claim 15 wherein the second read sensor has a first side and a second side opposite to the first side in a cross-track direction and wherein the first shield layer extends further from the first side in the cross-track direction than from the second side and wherein the second shield layer extends further from the second side in the cross-track direction than from the first side.
22. The method of claim 15 wherein the overlap has a first distance along the ABS and a second distance perpendicular to the ABS, the first distance being greater than the second distance.
23. The method of claim 15 wherein the insulating layer has a dielectric constant less than a silicon dioxide dielectric constant.
24. The method of claim 23 wherein insulating layer includes at least one of SiO and SiOC.
25. The method of claim 15 wherein the insulating layer has a first thickness within a first distance of the first and second read sensors and a second thickness more than a second distance from the first read sensor and second read sensor, the first thickness being less than the second thickness.
26. The method of claim 25 wherein the first distance is five microns.
27. The method of claim 25 wherein the first thickness is at least ten nanometers and wherein the second thickness is at least twenty nanometers.