Low magnetic flux density interface layer for spin torque oscillator
A magnetic field-assisted magnetic recording (MAMR) head is provided, which includes a recording main pole, a seed layer, and a spin torque oscillator (STO) positioned over the main pole, in this order, in a stacking direction from a leading side to a trailing side of the recording head. The STO comprises a spin polarized layer (SPL), an interlayer with fcc structure, and a field generating layer (FGL), in this order in the stacking direction. The FGL comprises a low magnetic flux density interface (LMFDI) layer with bcc structure that directly contacts the interlayer.
1. A magnetic field-assisted magnetic recording (MAMR) head comprising:
a recording main pole; and
a seed layer and a spin torque oscillator (STO) positioned over the main pole, in this order in a stacking direction from a leading side to a trailing side of the recording head, wherein
the STO comprises a spin polarized layer (SPL), an interlayer with fcc structure, and a field generating layer (FGL), in this order in the stacking direction, and
the FGL comprises at least three different magnetic materials, including a low magnetic flux density interface (LMFDI) layer with bcc structure that directly contacts the interlayer.
2. The MAMR head of claim 1 , wherein
the LMFDI layer comprises an alloy X-Y-Z comprising element X, element Y, and element Z, wherein
X is selected from a group consisting of Co and Fe,
Y is selected from a group consisting of Cr, Mn, Fe, and Co, and
Z is Al.
3. The MAMR head of claim 1 , wherein
the LMFDI layer comprises an alloy Co—Fe—Al.
4. The MAMR head of claim 1 , wherein
the LMFDI layer has a thickness of 7.5 to 10 Å.
5. The MAMR head of claim 1 , wherein
the FGL further comprises a Heusler layer directly contacting the LMFDI layer, the Heusler layer comprising a different material from the LMFDI layer, and the Heusler layer further comprises a magnetically unresponsive magnetic dead layer that directly contacts the LMFDI layer.
6. The MAMR head of claim 5 , wherein
the magnetic dead layer has a thickness of less than 5 Å.
7. The MAMR head of claim 5 , wherein
the Heusler layer comprises an alloy X-Y-Z comprising element X, element Y, and element Z, wherein
X is selected from a group consisting of Co and Fe,
Y is selected from a group consisting of Cr, Mn, Fe, and Co, and
Z is selected from a group consisting of Si and Ge.
8. The MAMR head of claim 7 , wherein
the Heusler layer comprises an alloy Co—Mn—Ge.
9. The MAMR head of claim 1 , wherein
the seed layer comprises a bcc layer positioned above an hcp layer or fcc layer.
10. The MAMR head of claim 1 , wherein the FGL comprises the LMFDI layer, a Heusler layer directly contacting the LMFDI layer, and a CoFe layer directly contacting the Heusler layer.
11. The MAMR head of claim 1 , wherein
the LMFDI layer comprises an alloy Co—Mn—Al.
12. A hard disk drive comprising the MAMR head of claim 1 .
13. A magnetic field-assisted magnetic recording (MAMR) head comprising:
a recording main pole; and
a seed layer and a STO positioned over the main pole, in this order in a stacking direction from a leading side to a trailing side of the recording head, wherein
the STO comprises a field generating layer (FGL), an interlayer with fcc structure, and a spin polarized layer (SPL), in this order in the stacking direction, and
the SPL comprises a LMFDI layer with bcc structure that directly contacts the interlayer.
14. The MAMR head of claim 13 , wherein
the LMFDI layer comprises an alloy X-Y-Z comprising element X, element Y, and element Z, wherein
X is selected from a group consisting of Co and Fe,
Y is selected from a group consisting of Cr, Mn, Fe, and Co, and
Z is Al.
15. The MAMR head of claim 14 , wherein
the LMFDI layer comprises an alloy Co—Fe—Al or Co—Mn—Al.
16. The MAMR head of claim 13 , wherein
the LMFDI layer has a thickness of 7.5 to 10 Å.
17. The MAMR head of claim 13 , wherein
the SPL further comprises a Heusler layer directly contacting the LMFDI layer, the Heusler layer comprising a different material from the LMFDI layer, and the Heusler layer further comprises a magnetically unresponsive magnetic dead layer that directly contacts the LMFDI layer.
18. The MAMR head of claim 17 , wherein
the magnetic dead layer has a thickness of less than 5 Å.
19. The MAMR head of claim 17 , wherein
the Heusler layer comprises an alloy X-Y-Z comprising element X, element Y, and element Z, wherein
X is selected from a group consisting of Co and Fe,
Y is selected from a group consisting of Cr, Mn, Fe, and Co, and
Z is selected from a group consisting of Si and Ge.
20. The MAMR head of claim 19 , wherein
the Heusler layer comprises an alloy Co—Mn—Ge.
21. The MAMR head of claim 13 , wherein
the seed layer comprises a bcc layer positioned above an hcp layer or fcc layer.
22. A hard disk drive comprising the MAMR head of claim 13 .