Energy assisted magnetic recording head having a near field transducer with reduced thermal protrusion
View Patent ↗An energy assisted magnetic recording head comprises a slider having a leading edge, a trailing edge, and an air bearing surface (ABS), and a near field transducer (NFT) disposed in the slider and having a distal end proximate the ABS. The distal end is recessed from the ABS when no optical power is applied to the NFT, and is co-planar with the ABS when a predetermined amount of optical power is applied to the NFT. A portion of the slider surrounding the distal end forms a concave surface having a continuously varying slope when no optical power is applied to the NFT, and a flat surface coplanar with the ABS and the distal end when the predetermined amount of optical power is applied to the NFT. Applying optical power comprises coupling light into a waveguide formed in the head and directing the coupled light to the NFT via the waveguide.
1. An energy assisted magnetic recording (EAMR) head comprising:
a slider having a leading edge, a trailing edge, and an air bearing surface (ABS); and
a near field transducer disposed in the slider and having a distal end proximate the ABS;
wherein:
the distal end of the near field transducer is recessed from the ABS when no optical power is applied to the near field transducer, and is co-planar with the ABS when a predetermined amount of optical power is applied to the near field transducer,
a portion of the slider surrounding the distal end forms a concave surface having a continuously varying slope when no optical power is applied to the near field transducer, and a flat surface coplanar with the ABS and the distal end of the near field transducer when the predetermined amount of optical power is applied to the near field transducer, and
wherein applying the optical power comprises coupling light into a waveguide formed in the EAMR head and directing the coupled light to the near field transducer via the waveguide.
2. The EAMR head of claim 1 , further comprising:
a laser diode integrated on the slider, the laser diode configured to supply laser light to the near field transducer during a recording operation of the EAMR head.
3. The EAMR head of claim 1 , wherein the waveguide is optically coupled to the near field transducer.
4. The EAMR head of claim 1 , wherein the waveguide is configured to direct laser light received from an external laser to the near field transducer during a recording operation of the EAMR head.
5. The EAMR head of claim 1 , wherein the predetermined amount of optical power is an operational level of optical power during a recording operation of the EAMR head.
6. The EAMR head of claim 1 , wherein the concave curvilinear surface is formed during fabrication of the magnetic head by removing a portion of the near field transducer protruding beyond the ABS while applying optical power to the near field transducer.
7. The EAMR head of claim 6 , wherein the applying optical power to the near field transducer and the removing the protruded portion thereof are iteratively repeated, wherein a greater level of optical power is applied to the near field transducer in each iteration, and wherein the greater level of optical power in each iteration causes a further portion of the near field transducer to protrude.
8. The EAMR head of claim 7 , wherein a level of optical power applied to the near field transducer in a final iteration is an operational level of optical power for use during a recording operation of the EAMR head.
9. The EAMR head of claim 6 , wherein the applying optical power to the near field transducer and the removing the protruded portion thereof occur concurrently, and wherein the optical power applied to the near field transducer is gradually increased while removing a protruded portion of the near field transducer.
10. The EAMR head of claim 7 , wherein the optical power applied to the near field transducer is increased to an operational level of optical power for use during a recording operation of the EAMR head.