Stitched wrap around shield fabrication for perpendicular magnetic recording write heads
View Patent ↗A wrap around shield of a write head is fabricated in multiple processes, with side shields fabricated in one process, and a trailing shield formed in another process. These multiple processes form a stitched wrap around shield, resulting in more flexible and accurate placement of the trailing shield and side shields with respect to the write pole. These processes also independently form the dimensions (shapes and sizes) of the side shields and the trailing shield which allows better control of writeability, saturation, and adjacent track interference of the perpendicular recording write head.
1. A method for forming a write head, the method comprising:
forming a write pole of the write head;
forming side shield gap structures on side regions of the write pole;
forming side shields on the side regions of the write pole by:
depositing a first layer of non-magnetic material;
depositing a layer of side shield material;
removing a portion of the layer of side shield material above the write pole by performing a chemical mechanical polishing (CMP) process on the layer of side shield material, wherein the first layer of non-magnetic material acts as a CMP stop layer during the CMP process; and
removing the first layer of non-magnetic material above the write pole, wherein the side shield gap structures define a first gap separating the write pole and the side shields;
forming a trailing shield gap structure above the write pole by:
depositing a second layer of non-magnetic material; and
fabricating contacts in the second layer of non-magnetic material on each side of the write pole to allow contact between the side shields and a trailing shield; and
forming the trailing shield of the write head, wherein the trailing shield gap structure defines a second gap separating the write pole and the trailing shield, and wherein the second gap is less than the first gap.
2. The method of claim 1 , wherein removing the first layer of non-magnetic material above the write pole further comprises:
milling the first layer of non-magnetic material above the write pole.
3. The method of claim 1 , wherein fabricating contacts in the second layer of non-magnetic material on the side regions of the write pole further comprises:
milling the second layer of non-magnetic material on the side regions of the write pole.
4. The method of claim 1 , wherein a thickness of the first gap is between about 20 nm and about 200 nm.
5. The method of claim 1 , wherein a thickness the second gap is between about 10 nm and about 50 nm.
6. The method of claim 1 , wherein forming the trailing shield further comprises:
depositing a layer of trailing shield material above the second layer of non-magnetic material; and
performing a CMP process on the trailing shield material to planarize the trailing shield material.