Magnetic memory element, method of driving same, and nonvolatile storage device
AssigneeFuji Electric Co., Ltd.
InventorYasushi Ogimoto
Life of this patent
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Abstract
In order to obtain a memory cell of size 4 F2 to realize cross-point type memory, a magnetic memory element is used having a spin valve structure including a free layer 5, nonmagnetic layer 4, and layer 3. The layer or the free layer includes an N-type ferrimagnetic material, and the magnetic compensation point of the N-type ferrimagnetic material is lower than the temperature reached by the layer when a certain write pulse is applied to control the combination of magnetizations of the free layer and layer, and higher than the temperature reached by the layer when another write pulse is applied. These write pulses can have the same polarity.
Claims23
A magnetic memory element, comprising:
- a spin valve structure having a free layer, a nonmagnetic layer, and a pinned layer, the pinned layer and the free layer sandwiching the nonmagnetic layer, such that information is recordable therein by applying an electric pulse across the free layer and the pinned layer, wherein
- a selected one of the pinned layer and the free layer includes a ferrimagnetic layer made of an N-type ferrimagnetic material, a magnetic compensation point Tcomp of the N-type ferrimagnetic material being in a storage retention operation temperature range of the magnetic memory element.
A method of driving a magnetic memory element, which has a spin valve structure having a free layer, a nonmagnetic layer, and a pinned layer, the pinned layer and the free layer sandwiching the nonmagnetic layer, and a selected one of the pinned layer and the free layer including a ferromagnetic layer made of an N-type ferrimagnetic material, a magnetic compensation point Tcomp of the N-type ferrimagnetic material being in a storage retention operation temperature region of the magnetic memory element, the method comprising:
- applying a first write pulse to the spin valve structure, to cause a combination of magnetization of the free layer and magnetization of the pinned layer to be in a first combination state;
- and
- applying a second write pulse to the spin valve structure, to cause the combination of the magnetization of the free layer and the magnetization of the pinned layer to be in a second combination state, wherein
- if the pinned layer is the selected layer, the magnetizations of the pinned layer, upon applications of the first and second write pulses, have mutually different orientations, and, if the free layer is the selected layer, the magnetizations of the free layer, upon applications of the first and second write pulses, have a same orientation, and
- the first and second write pulses are both electric pulse and have a same polarity.
Dependencies are inferred from the claim text.