Magnetic memory
According to one embodiment, a magnetic memory includes magnetoresistive effect elements each including a first magnetic layer, a tunnel barrier layer, and a second magnetic layer which are successively stacked, and a ferroelectric capacitor provided above the magnetoresistive effect elements via an insulating layer, and including a lower electrode, a ferroelectric film, and an upper electrode which are successively stacked.
1. A magnetic memory comprising:
magnetoresistive effect elements each including a first magnetic layer, a tunnel barrier layer, and a second magnetic layer which are successively stacked; and
a ferroelectric capacitor provided above the magnetoresistive effect elements via an insulating layer, and including a lower electrode, a ferroelectric film, and an upper electrode which are successively stacked.
2. The magnetic memory of claim 1 , wherein each of the first magnetic layer and the second magnetic layer has a magnetic anisotropy in a perpendicular direction to a film surface.
3. The magnetic memory of claim 2 , further comprising an insulating layer provided on the ferroelectric capacitor and having a Young's modulus which is lower than a Young's modulus of the ferroelectric film.
4. The magnetic memory of claim 1 , wherein each of the first magnetic layer and the second magnetic layer includes an alloy containing cobalt (Co) and iron (Fe).
5. The magnetic memory of claim 1 , wherein the tunnel barrier layer includes magnesium oxide (MgO).
6. The magnetic memory of claim 1 , wherein a voltage, which is applied between the lower electrode and the upper electrode, is different between a case in which data is written to the magnetoresistive effect element and a case in which the magnetoresistive effect element retains data.
7. The magnetic memory of claim 2 , wherein a voltage is applied between the lower electrode and the upper electrode such that a strain in the perpendicular direction of the ferroelectric film decreases when data is written to the magnetoresistive effect element.
8. The magnetic memory of claim 2 , wherein a voltage is applied between the lower electrode and the upper electrode such that a strain in the perpendicular direction of the ferroelectric film increases when the magnetoresistive effect element retains data.
9. The magnetic memory of claim 1 , further comprising a driver electrically connected to the upper electrode and the lower electrode and configured to apply a voltage between the upper electrode and the lower electrode.
10. The magnetic memory of claim 1 , further comprising select transistors formed on a semiconductor substrate,
wherein one end of a current path of each of the select transistors is electrically connected to one end of each of the magnetoresistive effect elements.
11. The magnetic memory of claim 1 , wherein each of the first magnetic layer and the second magnetic layer has a magnetic anisotropy in an in-plane direction.
12. The magnetic memory of claim 11 , further comprising an insulating layer provided on the ferroelectric capacitor and having a Young's modulus which is equal to or higher than a Young's modulus of the ferroelectric film.
13. A magnetic memory comprising:
a magnetoresistive effect element including a first magnetic layer, a tunnel barrier layer, and a second magnetic layer which are successively stacked;
a ferroelectric layer covering a top surface and a side surface of the magnetoresistive effect element; and
a first electrode and a second electrode provided in the ferroelectric layer in a manner to sandwich the magnetoresistive effect element from both sides.
14. The magnetic memory of claim 13 , wherein each of the first magnetic layer and the second magnetic layer has a magnetic anisotropy in a perpendicular direction to a film surface.
15. The magnetic memory of claim 13 , wherein each of the first magnetic layer and the second magnetic layer includes an alloy containing cobalt (Co) and iron (Fe).
16. The magnetic memory of claim 13 , wherein the tunnel barrier layer includes magnesium oxide (MgO).
17. The magnetic memory of claim 13 , wherein a voltage, which is applied between the first electrode and the second electrode, is different between a case in which data is written to the magnetoresistive effect element and a case in which the magnetoresistive effect element retains data.
18. The magnetic memory of claim 14 , wherein a voltage is applied between the first electrode and the second electrode such that a strain in an in-plane direction of the ferroelectric layer decreases when data is written to the magnetoresistive effect element.
19. The magnetic memory of claim 14 , wherein a voltage is applied between the first electrode and the second electrode such that a strain in an in-plane direction of the ferroelectric layer increases when the magnetoresistive effect element retains data.
20. The magnetic memory of claim 13 , further comprising a driver electrically connected to the first electrode and the second electrode and configured to apply a voltage between the first electrode and the second electrode.
21. The magnetic memory of claim 13 , wherein the ferroelectric layer comprises PZT [Pb(Zr, Ti)O 3 ], a BiTiO-based material, a BiSiO-based material, an SrTaNbO-based material, an SrBiTaO-based material, or a BiLaTiO-based material.