Magnetic head with stitched top pole layer and single layer coil or solenoidal coil
View Patent ↗A magnetic head is disclosed that has first and second substantially flat soft magnetic pole layers that are magnetically coupled together in a backgap region that is removed from the medium-facing surface; a soft magnetic pedestal having a leading edge and a trailing edge, the trailing edge adjoining the second pole layer adjacent to the medium-facing surface, the leading edge defining a throat area that is spaced from the first pole layer by a submicron nonferromagnetic gap and defining an apex area that is spaced from the first pole layer by a greater separation than the gap, the throat area meeting the apex area at a throat height; and a plurality of substantially parallel, electrically conductive sections disposed between the first and second pole layers, the conductive sections disposed in a single layer that is aligned along a plane that intersects the pedestal and the backgap region.
1. A magnetic head for writing information on a relatively-moving medium, the head having a leading end, a trailing end and a medium-facing surface, the head comprising:
a first substantially flat soft magnetic pole layer disposed in the head adjacent to the medium-facing surface and extending substantially perpendicular to the medium-facing surface, wherein a portion of the first magnetic pole layer adjacent to the medium-facing surface has a first medium-facing area substantially at the medium-facing surface;
a second substantially flat soft magnetic pole layer disposed between the first pole layer and the trailing end, oriented substantially parallel to the first pole layer, spaced greater than one micron from the first pole layer and magnetically coupled to the first pole layer in a backgap region that is removed from the medium-facing surface, wherein the second pole layer is recessed from the medium-facing surface;
a third pole layer extending substantially perpendicular to the medium-facing surface, the third pole layer residing between the second pole layer and the trailing end and being magnetically coupled with the second pole layer, a portion of the third pole layer disposed adjacent to the medium-facing surface, the portion having a second medium-facing area, wherein the first medium-facing area is at least two orders of magnitude greater than the second medium-facing area; and
an electrically conductive coil that encircles the second pole layer, the coil including a plurality of substantially parallel, electrically conductive sections disposed in a coil layer that is located between the first and second pole layers, each of the conductive sections having a portion substantially parallel to the medium-facing surface, the portion having a length measured in a direction that is substantially parallel to the medium-facing surface, wherein the length of at least two of the portions of the conductive sections is different.
2. The head of claim 1 , wherein the conductive sections each have an end portion disposed in the coil layer and extending transversely to the remainder of that section.
3. The head of claim 2 , wherein at least one of the end portions extends substantially perpendicular to the medium-facing surface.
4. The head of claim 2 , wherein at least one of the end portions provides a connection to a portion of the coil that extends between the second pole layer and the trailing end.
5. The head of claim 1 , further comprising a soft magnetic pedestal disposed adjacent to the medium-facing surface between the first and second pole layers, the pedestal adjoining one of the pole layers and spaced from the other pole layer by a submicron nonferromagnetic gap.
6. The head of claim 5 , wherein the pedestal has a leading edge and a trailing edge, the trailing edge adjoining the second pole layer adjacent to the medium-facing surface, the leading edge defining a throat area that is spaced from the first pole layer by the gap and defining an apex area that is spaced from the first pole layer by a greater separation than the gap, the throat area meeting the apex area at a throat height.
7. The magnetic head of claim 1 wherein the electrically conductive coil further includes an additional plurality of conductive sections disposed between the second pole layer and the trailing end, each of the additional plurality of coil sections having a portion extending substantially parallel to the medium-facing surface, the portion of the additional plurality of conductive sections having an additional length measured in the direction substantially parallel to the medium-facing surface, wherein the additional length of at least two of the additional plurality of conductive sections is different.
8. The magnetic head of claim 7 wherein the portion of each of the plurality of conductive sections extends substantially across the entire conductive section and the portion of each of the additional plurality of conductive sections extend substantially across the entirety of each of the additional plurality of conductive sections.