Hybrid diffuser for minimizing thermal pole tip protrusion and reader sensor temperature
View Patent ↗An enchance recording head design provides conduction and mechanical restraint control in order to minimize the pole tip protrusion and the head temperature resulting from the thermal heating of the magnetic recording head during operation. In one embodiment, the recording head includes a hybrid diffuser formed within an insulation layer, at a predetermined distance from the head write section. The hybrid diffuser is comprised of a thermal conduction layer with high thermal conductivity, such as gold or copper, and a mechanical restraint layer having near zero CTE, such as a 60-80% face-centered-cubic NiFe (Invar) material. The hybrid diffuser is recessed from the ABS to prevent the delamination of the hybrid diffuser due to the otherwise displacement incompatibility between the inner insulating layer and the hybrid diffuser at the ABS.
1. A head with thermal diffusion and mechanical expansion control, comprising:
a write section;
a read section formed under the write section;
an insulation layer formed above the write section;
a hybrid diffuser formed within the insulation layer, at a predetermined distance from the write section, and comprised of:
a thermal conduction layer with high thermal conductivity; and
a mechanical restraint layer having near zero CTE, to provide mechanical retention for controlling undesirable pole tip protrusion of the head, and to dissipate heat away from the write section and the read section.
2. The head of claim 1 , wherein the mechanical restraint layer is made of a face-centered-cubic metal alloy.
3. The head of claim 2 , wherein the mechanical restraint layer is made of NiFe Invar.
4. The head of claim 3 , wherein the mechanical restraint layer is made of a 60-80% face-centered cubic NiFe.
5. The head of claim 1 , wherein the thermal conduction layer has a thermal conductivity that enables the thermal conduction layer to diffuse high temperature within the head.
6. the head of claim 1 , wherein the mechanical restrin layeris formed over subtantially the entire surface of the write section.
7. The head of claim 6 , wherein the the hybrid diffuser divides the insulating layer into an inner insulating layer and an outer insulating layer.
8. The head of claim 7 , wherein the inner isulating layer is compossed of alumina.
9. The head of claim 7 , wherein the outer isulating layer is compossed of alumina.
10. The head of claim 1 , wherein the the hybrid diffuser divides from an air bearing surface by a predetermined recess distance.
11. The head of claim 10 , wherein the recess distanmce range between approximately 5 and 10 microns.
12. The head claim 1 , wherein the write section is comprised of a afrist pole layer P 1 , asecond pole layer P 2 .
13. The head of claim 13 , wherein the mechanical restrain layer is disposed atop, and in direct contact with the thermal conduction layer.
14. the head of claim 13 , wherein the mechanical restrint layer and the thermal conduction layer have a similar thickness, that can vary beetween approximately 2.5 and 5 microns.