Heat-assisted magnetic recording (HAMR) head with diffusion barrier between waveguide core and write pole lip
A heat-assisted magnetic recording (HAMR) head in which the core of the optical waveguide has an end face that abuts the NFT and the write pole lip has a diffusion barrier between the end face of the waveguide core and the write pole lip. The diffusion barrier layer may also be located between the waveguide core end face and the NFT, in which case it is formed of an optically transparent material, like TaN x , TiN x , ZrN x , HfN x , NbN x , CrN x , VN x , TiC, TaC, WC, SiC or SiN x , or a layer of Au, Ru, Rh or Ir with a thickness less than 5 nm. In addition to being located between both the NFT and the write pole lip and the waveguide core end face, the diffusion barrier layer may also be located between the waveguide core and the lower waveguide cladding layer.
1. A heat-assisted magnetic recording (HAMR) head for writing to a magnetic recording layer comprising:
a head carrier having a recording-layer-facing surface;
a write pole on a surface orthogonal to the recording-layer-facing surface of the head carrier and having a lip at the recording-layer-facing surface;
an optical waveguide on the head carrier having a core oriented parallel to the write pole and an end face recessed from and parallel to the recording-layer-facing surface;
a diffusion barrier layer sandwiched between the write pole lip and the waveguide core end face; and
a near-field transducer (NFT) layer on the head carrier at the recording-layer-facing surface and optically coupled to the waveguide core end face.
2. The HAMR head of claim 1 wherein the diffusion barrier layer is formed of an optically opaque material.
3. The HAMR head of claim 2 wherein the diffusion barrier layer is formed of a material selected from Au, Ru, Rh and Ir.
4. The HAMR head of claim 1 wherein the diffusion barrier layer is also sandwiched between the NFT and the waveguide core end face.
5. The HAMR head of claim 4 further comprising a layer of SiO 2 between the waveguide core end face and the portion of the diffusion barrier layer adjacent the NFT for improving the optical efficiency of the optical waveguide.
6. The HAMR head of claim 4 wherein the diffusion barrier layer is formed of an optically transparent material.
7. The HAMR head of claim 6 wherein the optically transparent material is selected from TaN x , TiN x , ZrN x , HfN x , NbN x , CrN x , VN x , TiC, TaC, WC, SiC and SiN x .
8. The HAMR head of claim 6 wherein the diffusion barrier layer is a layer having a thickness less than or equal to 5 nm and greater than or equal to 0.5 nm and selected from Au, Ru, Rh and Ir.
9. The HAMR head of claim 1 wherein the optical waveguide further comprises a first cladding layer, the waveguide core being located on the first cladding layer, and a second cladding layer between the waveguide core and the write pole, and wherein the diffusion barrier layer is also located between the waveguide core and the first cladding layer.
10. The HAMR head of claim 9 further comprising a layer of SiO 2 between the waveguide core and the portion of the diffusion barrier layer adjacent the first cladding layer for improving the optical efficiency of the optical waveguide.
11. The HAMR head of claim 1 further comprising an adhesion layer selected from Si, Ti, Ta and Cr between the write pole lip and the waveguide core end face.
12. The HAMR head of claim 11 wherein the adhesion layer is located between the write pole lip and the diffusion barrier layer.
13. The HAMR head of claim 1 wherein the diffusion barrier layer has a thickness less than or equal to 10 nm and greater than or equal to 0.5 nm.
14. The HAMR head of claim 1 wherein the NFT is selected from an E-shaped antenna, a C-shaped aperture, a bowtie-shaped aperture, and a bowtie-shaped antenna.
15. A heat-assisted magnetic recording (HAMR) disk drive comprising:
the HAMR head of claim 1 ;
a laser for directing light to the waveguide; and
a magnetic recording disk having a magnetic recording layer.
16. The HAMR disk dive of claim 15 wherein the magnetic recording layer is patterned into concentric tracks containing discrete islands of magnetic material.
17. A heat-assisted magnetic recording (HAMR) head for writing to a magnetic recording layer in a disk drive comprising:
an air-bearing slider having an air-bearing surface (ABS) for facing the recording layer;
a write pole on a slider surface orthogonal to the ABS and having a lip at the ABS;
a near-field transducer (NFT) layer on the slider at the ABS;
an optical waveguide on the slider for transmitting light to the NFT and having a core oriented parallel to the write pole and an end face recessed from and parallel to the ABS, the waveguide core end face facing the write pole lip and the NFT;
a diffusion barrier layer sandwiched between the waveguide core end face and both the write pole lip and the NFT, the diffusion barrier layer being formed of a material optically transparent to the light.
18. The HAMR head of claim 17 wherein the diffusion barrier layer is a layer having a thickness less than or equal to 10 nm and greater than or equal to 0.5 nm and selected from TaN x , TiN x , ZrN x , HfN x , NbN x , CrN x , VN x , TiC, TaC, WC, SiC and SiN x or a layer having a thickness less than or equal to 5 nm and greater than or equal to 0.5 nm and selected from Au, Ru, Rh and Ir.
19. The HAMR head of claim 17 wherein the optical waveguide further comprises a first cladding layer, the waveguide core being located on the first cladding layer, and a second cladding layer between the waveguide core and the write pole, and wherein the diffusion barrier layer is also located between the waveguide core and the first cladding layer.
20. The HAMR head of claim 17 further comprising an adhesion layer selected from Si, Ti, Ta and Cr between the write pole lip and the waveguide core end face.