Method of making narrow track width magnetoresistive sensor
View Patent ↗A method and system for forming a microscopic transducer are described. The method and system include forming a plurality of adjoining sensor layers. The sensor layers include a first magnetically soft layer, a nonmagnetic layer on the first magnetically soft layer, and a second magnetically soft layer on the nonmagnetic layer. The method and system also include forming a sidewall over the second magnetically soft layer. The sidewall formation includes forming a base having a surface oriented substantially perpendicular to the sensor layers and depositing an electrically conductive material on the surface. The method and system also include removing a portion of the sensor layers not covered by the sidewall.
1. A method for forming a microscopic transducer, the method comprising:
forming a plurality of adjoining sensor layers, including:
depositing a first magnetically soft layer,
depositing a nonmagnetic layer on said first magnetically soft layer, and
depositing a second magnetically soft layer on said nonmagnetic layer,
forming a sidewall over said second magnetically soft layer, including
forming a base having a surface oriented substantially perpendicular to said sensor layers, and
depositing an electrically conductive material on said surface; and
removing a portion of said sensor layers not covered by said sidewall.
2. The method of claim 1 , wherein forming said sidewall layer further comprises:
forming an electrically conductive layer having a first portion oriented along said surface and having a second portion oriented transverse to said surface, and
removing said second portion.
3. The method of claim 2 , wherein removing said second portion includes impinging a beam of particles upon said layer.
4. The method of claim 1 , wherein depositing said electrically conductive material includes sputtering said material onto said surface.
5. The method of claim 1 , wherein depositing said electrically conductive material includes depositing a magnetically soft magnetic material onto said surface.
6. The method of claim 1 wherein depositing said electrically conductive material includes depositing a nonmagnetic material onto said surface.
7. The method of claim 1 , further comprising:
removing said base, prior to removing said portion of said sensor layers not covered by said sidewall layer.
8. The method of claim 1 , further comprising:
depositing an insulating material having a slower etch rate than said electrically conductive material, adjacent to said sidewall.
9. The method of claim 8 , further comprising:
removing a portion of said sidewall and said insulating material, thereby creating a tapered region of said insulating material adjacent to said sidewall.
10. The method of claim 1 , further comprising:
forming a plurality of bias layers adjacent to one of said magnetically soft layers.
11. The method of claim 1 , further comprising:
forming an inductive transducer, including forming a tip layer oriented in a direction substantially perpendicular to said nonmagnetic layer and on an additional sidewall.
12. The method of claim 1 , wherein forming said electrically conductive layer includes depositing a nonmagnetic material onto said major surface and said side surface.
13. A method for forming a microscopic transducer, the method comprising:
forming a plurality of adjoining sensor layers that are substantially parallel to a plane;
forming an electrically conductive sidewall layer over said sensor layers such that said sidewall layer extends many times further in a direction substantially perpendicular to said plane than in a direction substantially parallel to said plane; and
removing regions of said sensor layers not covered by said sidewall layer.
14. The method of claim 13 , wherein forming an electrically conductive sidewall layer comprises:
forming a base layer on said sensor layers, said base layer having a major surface that is substantially parallel to said plane and a side surface that is substantially perpendicular to said plane;
forming an electrically conductive layer that coats said major surface and said side surface; and
removing said electrically conductive layer that coats said major surface.
15. The method of claim 14 , wherein removing said electrically conductive layer that coats said major surface includes ion beam etching.
16. The method of claim 14 , wherein forming said electrically conductive layer includes sputtering electrically conductive material onto said major surface and said side surface.
17. The method of claim 14 wherein forming said electrically conductive layer includes depositing a magnetically soft material onto said major surface and said side surface.
18. The method of claim 14 , further comprising:
removing said base layer, prior to removing said regions of said layers not covered by said sidewall layer.
19. The method of claim 13 , further comprising:
depositing an insulating material adjacent to said sidewall layer that has a slower etch rate than said sidewall layer.
20. The method of claim 19 , further comprising:
removing a portion of said sidewall layer and said insulating material, thereby creating a tapered region of said insulating material adjacent to said sidewall layer.
21. The method of claim 13 , further comprising:
forming a plurality of bias layers adjacent to said sidewall layer.
22. A method for forming a microscopic transducer, the method comprising:
forming a plurality of adjoining sensor layers that are substantially parallel to a plane;
a step for forming an electrically conductive sidewall layer over said sensor layers such that said sidewall layer extends many times further in a direction substantially perpendicular to said plane than in a direction substantially parallel to said plane; and
removing regions of said sensor layers not covered by said sidewall layer;
depositing an insulating material adjacent to said sidewall layer that has a slower etch rate than said sidewall layer; and;
removing a portion of said sidewall layer and said insulating material, thereby creating a tapered region of said insulating material adjacent to said sidewall layer.
23. The method of claim 22 , herein said sidewall layer is magnetically soft.
24. The method of claim 22 , wherein said sidewall layer is nonmagnetic.