Manufacturing a narrow track read head
View Patent ↗Embodiments of the invention operate to narrow the track width of a read head used in a disk drive. In one embodiment, a magnetic read head has a track width of about 40 nm or less. The read head is fabricated by a method that includes fabricating a film stack from a substrate, a sensor material, a stop material, a first release material, a mask material, and a photo resist material. The mask material may include a masking substrate material and a second release material. The film stack is processed by forming a read head image in the photo resist material, removing portions of the film stack that lie outside the read head image of the photo resist material, stripping the film stack to remove the photo resist, mask and first release materials, and milling the sensor material according to the read head image.
1. A method of manufacturing a read head, the method comprising:
fabricating a film stack by:
forming a sensor layer on a substrate, wherein the sensor layer is configured from a magnetic material;
forming a stop layer on the sensor layer, wherein the stop layer is configured from a material that deters removal of the sensor layer during chemical mechanical polishing;
forming a release layer on the stop layer, wherein the release layer is configured from a first release material;
forming a mask layer on the release layer, wherein the mask layer is configured from a material that transfers an image of the read head from a photo resist layer onto the release layer, wherein the step of forming the mask layer comprises layering a second release material between the mask layer and the photo resist layer; and forming the photo resist layer on the mask layer; and
patterning the read head image in the photo resist layer;
etching the stop layer, the release layer and the mask layer according to the patterned read head image;
stripping the photo resist layer, the release layer and the mask layer; and
milling the sensor layer according to the patterned read head image of the remaining stop layer.
2. The method of claim 1 , wherein the first and second release materials are polyamide materials.
3. The method of claim 1 , wherein the stop layer material is carbon.
4. The method of claim 1 , wherein the photo resist layer material is TIS.
5. The method of claim 1 , wherein the mask layer material includes Si 3 N 4 .
6. The method of claim 1 , wherein said etching the stop layer, the release layer, and the mask layer according to the patterned read head image comprises:
first reactive ion etching the mask layer using a first reactive ion etching material; and
second reactive ion etching the release layer and the stop layer using a second reactive ion etching material, wherein the first and second reactive ion etching materials are different.
7. The method of claim 6 , wherein the first reactive ion etching material is selected from a group consisting of CF 4 and CHF 3 and wherein the second reactive ion etching material is selected from a group consisting of O 2 and O 3 .
8. The method of claim 1 , wherein said patterning the read head image in the photo resist layer comprises first reactive ion etching the photo resist layer using a first reactive ion etching material to remove a portion of the photo resist layer and form the read head image.
9. The method of claim 8 , wherein said etching the stop layer, the release layer, and the mask layer according to the patterned read head image comprises:
second reactive ion etching the mask layer material using a second reactive ion etching material; and
third reactive ion etching the release layer and the stop layer using a third reactive ion etching material wherein the first and second reactive ion etching materials are different.
10. The method of claim 9 , wherein the third reactive ion etching material is selected from a group consisting of CO 2 and O 2 .
11. The method of claim 1 , further comprising:
encasing the read head with two or more encasing materials;
wherein said chemical mechanical polishing is performed on the read head to remove a portion of the two or more encasing materials from the read head; and
notching the read head.
12. The method of claim 1 , wherein the mask layer is selected from a group consisting of: Si 3 N 4 ; SiO 2 ; SiO x N y ; Ta: Ta 2 N 3 : Ta 2 O 5 : and W.