Magnetic tunnel junction device, method for manufacturing magnetic tunnel junction device, and magnetic memory
Provided are a magnetic tunnel junction dement suppressing diffusion and penetration of constituent elements between a hard mask film, and a magnetic tunnel junction film and a protection layer, and a method for manufacturing the magnetic tunnel junction element. The magnetic tunnel junction element has a configuration in which a non-magnetic insertion layer ( 7 ) including Ta or the like is inserted beneath a hard mask layer ( 8 ).
1. A magnetic tunnel junction element, comprising:
a reference layer having a magnetization direction that is fixed;
a tunnel barrier layer disposed adjacent to the reference layer;
a recording layer having a magnetization direction that is variable, and disposed adjacent to the tunnel barrier layer on an opposite side thereof to the reference layer;
a first protection layer disposed adjacent to the recording layer on an opposite side thereof to the tunnel barrier layer;
a second protection layer disposed adjacent to the first protection layer on an opposite side thereof to the recording layer;
a non-magnetic insertion layer disposed adjacent to the second protection layer on an opposite side thereof to the first protection layer; and
a hard mask layer disposed in a direct contact with the non-magnetic insertion layer on an opposite side thereof to the second protection layer,
wherein
the reference layer includes a ferromagnetic body,
the tunnel barrier layer includes O,
the recording layer includes a ferromagnetic body including at least any of Co, Fe, or Ni,
the first protection layer includes O,
the second protection layer includes at least one from the group consisting of Ru, Co, Fe, CoB, FeB, CoFe, or CoFeB,
the non-magnetic insertion layer includes at least one from the group consisting of Ta, Nb, Mo, Hf, W, or Pt, and a film thickness of the non-magnetic insertion layer is 1 nm or more, and 10 nm or less,
the hard mask layer is a metal material including Ti or N, and
the reference layer, the tunnel barrier layer, and the recording layer configure a magnetic tunnel junction film (M) and a magnetization direction of each of the reference layer and the recording layer is perpendicular to a film surface.
2. A magnetic memory comprising the magnetic tunnel junction element according to claim 1 .
3. The magnetic tunnel junction element according to claim 1 , wherein the non-magnetic insertion layer is Ta.
4. The magnetic tunnel junction element according to claim 3 , wherein the first protection layer is MgO.
5. The magnetic tunnel junction element according to claim 1 , further comprising a third protection layer disposed adjacent to and between the second protection layer and the non-magnetic insertion layer, wherein
the third protection layer includes at least one from the group consisting of Ru, Rh, Cu, Ir, Au, Hf, W, Zr, Nb, Mo, Ti, V, or Cr, or an alloy thereof.
6. A magnetic memory comprising the magnetic tunnel junction element according to claim 5 .
7. A method for manufacturing a magnetic tunnel junction element, the method comprising:
sequentially laminating a magnetic tunnel junction film (M) including at least a reference layer, a tunnel barrier layer, and a recording layer, a first protection layer, a second protection layer, a non-magnetic insertion layer, and a hard mask layer;
annealing the laminated film;
laminating a sacrificial layer including at least Si on the hard mask layer subjected to annealing;
forming a photoresist having, on a part of the sacrificial layer, a processed pattern shape of the magnetic tunnel junction film (M) in a top view;
performing etching using the photoresist as a mask and processing the sacrificial layer;
performing etching using the sacrificial layer as a mask and processing the hard mask layer;
performing etching using the hard mask layer as a mask and processing the magnetic tunnel junction film (M); and
removing the sacrificial layer,
wherein:
the reference layer includes a ferromagnetic body,
the tunnel barrier layer includes O,
the recording layer includes a ferromagnetic body including at least any of Co, Fe, or Ni,
the first protection layer includes O,
the second protection layer includes at least one from the group consisting of Ru, Co, Fe, CoB, FeB, CoFe, or CoFeB,
the non-magnetic insertion layer includes at least one from the group consisting of Ta, Nb, Mo, Hf, W, or Pt, and a film thickness of the non-magnetic insertion layer is 1 nm or more, and 10 nm or less,
the hard mask layer is a metal material including Ti or N, and
a magnetization direction of each of the reference layer and the recording layer is perpendicular to a film surface.
8. The method for manufacturing a magnetic tunnel junction element according to claim 7 , further comprising a third protection layer disposed adjacent to and between the second protection layer and the non-magnetic insertion layer, wherein
the third protection layer includes at least one from the group consisting of Ru, Rh, Cu, Ir, Au, Hf, W, Zr, Nb, Mo, Ti, V, or Cr, or an alloy thereof.
9. The method for manufacturing a magnetic tunnel junction element according to claim 7 , wherein in the annealing, an annealing temperature is about 400° C., and annealing time is 1 hour.
10. The method for manufacturing a magnetic tunnel junction element according to claim 9 , wherein the etching in the processing the hard mask layer, and the etching in the processing the magnetic tunnel junction film (M) are each reactive ion etching or ion beam etching, and an incident angle of an ion beam is 50° to 90° with respect to a direction perpendicular to a film surface.