JP2000285668A - Magnetic memory device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a magnetic memory device capable of recording and reproducing information with a small operating magnetic field and with reduced influence on adjacent cells. SOLUTION: A magnetic memory element 1 arranged in a matrix, a magnetic field applying means 2 for applying a magnetic field to the magnetic memory element 1 for recording and reproducing information, and a magnetic field applying means only for a selected magnetic memory element 1 And an element heating means 3 for heating the magnetic memory element 1 so that the magnetic memory element 1 can be operated by the magnetic field from the element 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic memory device in which magnetic memory elements using a magnetoresistive effect are arranged in a matrix.

[0002]

2. Description of the Related Art In recent years, a random access memory utilizing a magnetoresistance effect has attracted attention as a solid-state recording element having high density, quick response, and non-volatility. According to such a magnetic memory element, information can be recorded according to the direction of magnetization of the magnetic layer, and a nonvolatile memory that holds recorded information semi-permanently can be obtained. Therefore, it is expected to be used as various recording elements such as information recording elements of portable terminals and cards. In particular, a magnetic memory element using the giant magnetoresistance effect (GMR) is expected because it can utilize the high output characteristics of GMR and can perform high-speed reading.

A specific cell structure of such a magnetic memory element using GMR is disclosed in, for example, Japanese Patent Application Laid-Open No. 9-9195.
Japanese Patent Laid-Open No. 1 discloses an integrated element structure in which write lines, read lines, and the like are arranged. In this integrated device structure, each memory cell is arranged in a matrix, connected in series by read lines in the horizontal direction, and a common write line is arranged on each cell in the vertical direction.

[0004]

However, as the degree of integration of memory cells increases, a magnetic field generated from a write line when information is recorded leaks to other adjacent cells, causing a problem such as malfunction. . Further, from the viewpoint of increasing the operation speed of the memory element, it is desired to record and reproduce information on the memory element with a small operating magnetic field.

An object of the present invention is to provide a magnetic memory device capable of recording and reproducing information with a small operating magnetic field and with reduced influence on adjacent cells.

[0006]

A magnetic memory device according to the present invention comprises: a magnetic memory element arranged in a matrix; magnetic field applying means for applying a magnetic field to the magnetic memory element for recording and reproducing information; and a magnetic memory element. And an element heating means for heating the selected magnetic memory element so that the magnetic memory element can be operated only by the magnetic field from the magnetic field applying means.

[0007] In the magnetic memory element of the present invention, recording and reproduction of information are performed using the magnetoresistance effect. Therefore, the magnetic memory element has a magnetoresistive film. It is preferable that the magnetoresistive film exhibit a giant magnetoresistive effect (GMR). Examples of such a magnetoresistive film include various types of magnetoresistive films of coercive force difference type, spin valve type and artificial lattice type. Among them, those using a tunnel type giant magnetoresistive film provided with a pair of ferromagnetic layers via an insulating layer are preferable because high output characteristics can be obtained and high-speed reading can be performed. Among such tunnel type giant magnetoresistive films, it is particularly preferable that the ferromagnetic layer is a perpendicularly magnetized ferromagnetic layer. Therefore, a tunnel type giant magnetoresistive film having two perpendicular magnetization layers and an insulating layer sandwiched therebetween is preferable.

FIG. 1 is a schematic configuration diagram for explaining a magnetic memory device according to the present invention. In the vicinity of the magnetic memory element 1, a magnetic field applying means 2 for applying a magnetic field for recording and reproducing information to the magnetic memory element 1 is provided.
Further, in the vicinity of the magnetic memory element 1, an element heating device for heating the magnetic memory element 1 to reduce the coercive force of the magnetic memory element 1 so that the magnetic memory element 1 can be operated by the magnetic field from the magnetic field applying unit 2. Means 3 are provided.
The magnetic memory element 1 heated to a predetermined temperature by the element heating means 3 records and reproduces information by a magnetic field from the magnetic field applying means 2. The magnetoresistive film of the magnetic memory element 1 is composed of, for example, a magnetoresistive film having a laminated structure in which a nonmagnetic layer is provided between a pair of ferromagnetic layers.

FIG. 3 is a diagram showing the relationship between the coercive force of the recording layer and the reproducing layer and the temperature in such a magnetic memory device. As shown in FIG. 3, as the temperature increases,
The coercive force of the recording layer and the coercive force of the reproducing layer are reduced. Therefore, it is understood that the coercive force of the recording layer and the reproducing layer can be reduced by increasing the temperature of the recording layer and the reproducing layer, and the operation can be performed with a smaller operating magnetic field. For example,
At room temperature Tc, the recording layer operable in the operating magnetic field range A can be operated in the smaller operating magnetic field range B by raising the temperature to the operating temperature Top. Therefore, information can be recorded with a small operating magnetic field. Similarly, by raising the temperature of the reproducing layer from the room temperature Tc to the operating temperature Top,
Reproduction can be performed with a smaller operating magnetic field.

FIG. 2 is a schematic configuration diagram for explaining a magnetic memory device according to the present invention. As described above, according to the present invention, information can be recorded and reproduced with a small operating magnetic field. According to the present invention, by selectively heating the magnetic memory element, only the selected magnetic memory element can be operated by the magnetic field from the magnetic field applying unit. As shown in FIG.
Causes the element heating means 3 provided in the vicinity of the selected magnetic memory element 1 to generate heat, thereby heating the selected magnetic memory element 1. In the selected magnetic memory element 1, the temperatures of the recording layer and the reproducing layer rise as described above, and information can be recorded or reproduced with a smaller operating magnetic field from the magnetic field applying unit 2. Since the magnetic memory element adjacent to the selected magnetic memory element 1 is not heated by the element heating means in the vicinity, it does not operate even with the same magnetic field strength, and information is recorded or reproduced. Nothing.

As described above, according to the present invention, by selectively heating the magnetic memory element by the element heating means,
Recording and reproduction of information can be performed only on the selected magnetic memory element by the magnetic field from the magnetic field applying means.

The magnetic field applying means in the present invention may be any as long as it can apply a magnetic field for recording and reproducing information to and from the magnetic memory element. A common word line may be arranged for each magnetic memory element in the horizontal direction, and a current may be applied to the word line to form a magnetic field applying unit.

The element heating means in the present invention may be any means capable of heating the selected magnetic memory element so that the magnetic memory element can be operated only by the magnetic field from the magnetic field applying means.

In a general configuration according to the present invention, the magnetic field application region to which the magnetic field is applied by the magnetic field application means is:
It is wider than the heating area heated by the element heating means. In other words, the heating area heated by the element heating means is configured to be narrower than the area to which the magnetic field is applied by the magnetic field applying means.

In a preferred embodiment according to the present invention, the first heating current line and the second heating current line are arranged along the matrix of the magnetic memory element so as to be orthogonal to each other, and The first heating current line and the second heating current line are provided so as to intersect on each magnetic memory element.
A resistance heating layer is provided so as to be interposed between the first heating current line and the second heating current line at the intersection of the heating current line and the second heating current line. To heat the selected magnetic memory element, a first intersecting first
A current flows between the heating current line and the second heating current line, and heat is generated in the resistance heating layer sandwiched between the heating current line and the second heating current line, so that the magnetic memory element can be heated. Accordingly, in such an embodiment, the element heating means is constituted by the first heating current line, the second heating current line, and the resistance heating layer sandwiched therebetween.

[0016]

FIG. 4 is a plan view showing one embodiment of a magnetic memory device according to the present invention. As shown in FIG. 4, the plurality of magnetic memory elements 10 are arranged in a matrix. On each magnetic memory element 10 arranged in a matrix, a read bit line 20
Is provided. The read bit line 20 is provided as a read bit line common to the magnetic memory elements 10 arranged in the horizontal direction.

Below each magnetic memory element 10, a word line 21 extending in the vertical direction is provided. Word line 21
Are provided as word lines common to the magnetic memory elements 10 arranged in the vertical direction. Below the word line 21, a resistance heating layer 22 is provided. Resistance heating layer 22
Below, a heating bit line 23 is provided in the same horizontal direction as the read bit line 20. The heating bit line 23
The magnetic memory elements 10 arranged in the horizontal direction are provided so as to serve as a common heating bit line.

The read bit line 20, the word line 21, and the heating bit line 23 are formed of Al in this embodiment. The resistance heating layer 22 is formed from SiN.

FIG. 5 is an enlarged schematic perspective view showing one of the magnetic memory elements 10 shown in FIG. As shown in FIG. 5, the magnetic memory element 10 is formed of a magnetoresistive film in which a reproducing layer 13 is stacked on a recording layer 11 with an insulating layer 12 interposed therebetween. The coercive force of the reproducing layer 13 is set to be smaller than the coercive force of the recording layer 11. Therefore, the magnetoresistive film used here is a coercive force difference type magnetoresistive film. In this embodiment,
The recording layer 11 is made of Co, and the insulating layer 12 is made of A
l is formed from ₂ O _3, the reproduction layer 13 is formed of NiFe. The magnetoresistance change of the magnetoresistance effect film including the recording layer 11, the insulating layer 12, and the reproduction layer 13 can be detected from the resistance change of the sense current flowing between the word line 21 and the read bit line 20.

A magnetic field for controlling the magnetization directions of the recording layer 11 and the reproducing layer 13 can be generated by passing a current through the word line 21. Therefore, in this embodiment, the word line 21 serves as a magnetic field applying unit.

In order to heat the magnetic memory element 10, a current flows between the word line 21 and the heated bit line 23. As a result, the portion of the resistance heating layer 22 sandwiched between the word lines 21 and the heating bit lines 23 at the intersections thereof generates heat, thereby causing the magnetic memory element 1 located thereabove.
0 can be heated. Therefore, in this embodiment, the element heating means is constituted by the word line 21, the resistance heating layer 22, and the heating bit line 23.

To heat the selected magnetic memory element, a current is passed between the word line 21 and the heating bit line 23 passing through the magnetic memory element, and the resistance at the intersection of the word line 21 and the heating bit line 23 is increased. By causing the heat generating layer 22 to generate heat, the magnetic memory element 10 can be heated.

FIGS. 6 and 7 are cross-sectional views for explaining the operation when information is recorded on the magnetic memory element shown in FIG. Referring to FIG. 6, a heating bit line 23 extending in the lateral direction of the matrix of the magnetic memory element is provided on a non-magnetic support substrate 24, and a resistance heating layer 22 is provided on heating bit line 23. Is provided. Resistance heating layer 22
A word line 21 extending in the vertical direction of the matrix of the magnetic memory elements is provided above. On the word line 21, a recording layer 11, an insulating layer 12, and a reproducing layer 13 constituting a magnetoresistive film of the magnetic memory element 10 are stacked. On the reproduction layer 13, a read bit line 20 extending in the horizontal direction of the matrix of the magnetic memory elements is provided. Insulating layers 25 and 26 are provided between the magnetic memory element 10 and an adjacent magnetic memory element. It is preferable that the insulating layers 25 and 26 have electrical insulating properties and also have thermal insulating properties. FIG. 6 shows a state in which information is recorded on the recording layer 11 by controlling the magnetization direction in the direction of “←”.

First, the recording layer 11 is heated to reduce the coercive force of the recording layer 11 and to set the magnetization direction with a small operating magnetic field. A word line 21 passing through the selected magnetic memory element 10 and a heating bit line 23 passing through the selected magnetic memory element 10 are selected, and an electric current is caused to flow between the word line 21 and the heating bit line 23 so that an intersection between the word line 21 and the heating bit line 23 is obtained. Causes the resistance heating layer 22 to generate heat. The heat generated from the resistance heating layer 22 is transmitted to the recording layer 11, and the recording layer 11 is heated and its coercive force is reduced. In this state, the word line 2
1, a magnetic field A is generated around the word line 21 by flowing a current in a direction from the back side to the front side in the drawing. When the magnetic field A is applied to the recording layer 11, the recording layer 1
The magnetization direction of No. 1 is set to the direction of “←”. Thereby, information is recorded on the recording layer 11.

In the cell (magnetic memory element) adjacent to the selected magnetic memory element 10, since the recording layer is not actively heated, the operating magnetic field is not reduced, and Is not affected by the magnetic field A generated from the word line 21. Therefore, in the adjacent cell, the magnetization direction is maintained, and the recorded information is maintained. Therefore, information can be recorded only in the selected magnetic memory element without affecting adjacent cells.

In the embodiment shown in FIG. 6, the magnetization direction of the reproducing layer 13 is set to the same direction as that of the recording layer 11.
At the time of recording on the recording layer 11, the magnetization direction of the reproducing layer 13 is not particularly related, so that the magnetization direction of the reproducing layer 13 may or may not change at the time of recording. Whether or not the magnetization direction of the reproducing layer 13 changes during recording on the recording layer 11 depends on the degree to which the reproducing layer 13 is heated and the coercive force and the strength of the magnetic field A at that temperature. .

As shown in FIG. 7, in order to set the magnetization direction of the recording layer 11 in the direction of “→”, a current flows between the word line 21 and the heating bit line 23 in the same manner as described above. Then, the resistance heating layer 22 is heated at the intersection, and the recording layer 11 is heated by this. Then, a current is applied to the word line 21 from the near side to the far side in the drawing. This current generates a magnetic field B, and the magnetization direction of the recording layer 11 is set in the direction of “→” by the magnetic field B. Similarly to the above, only the recording layer 11 of the selected magnetic memory element 10 is heated so that the magnetization direction is changed by the magnetic field B and the coercive force is reduced.
Only one is recorded by the magnetic field B. Therefore, information can be recorded only on the selected magnetic memory element without affecting the recording layer of the adjacent cell.

FIGS. 8 and 9 are cross-sectional views for explaining an operation when reproducing information recorded on the magnetic memory element 10. FIG. FIGS. 8 and 9 show a state in which information is reproduced when recording is performed by setting the magnetization direction of “→” in the recording layer 11 as shown in FIG.

When information recorded on the recording layer 11 is reproduced, a sense current is passed between the word line 21 and the read bit line 20 to detect a change in the resistance value of the magnetic memory element 10. In this embodiment, the insulating layer 12
Since the tunnel type magnetoresistive film in which the recording layer 11 and the reproducing layer 13 which are ferromagnetic layers are stacked is used, a sense current flows in the thickness direction of the magnetoresistive film.

As shown in FIG. 8, first, a current flowing from the near side to the far side of the drawing flows through the word line 21. Thereby, a magnetic field C is generated. The current flowing through the word line 21 is such that the magnetic field C generated by the word line 21 has a relatively large coercive force.
Of the reproducing layer 13 having a relatively small coercive force without changing the magnetization direction of the reproducing layer 13. Since the magnetization direction of the reproducing layer 13 is originally the direction of “→”, the magnetization direction is maintained.

Next, as shown in FIG. 9, the direction of the current flowing through the word line 21 is reversed, and the current flows from the back side to the near side in the drawing. As a result, a magnetic field D is generated.
As a result, only the magnetization direction of the reproducing layer 13 is reversed, and is set in the direction of “←”. Accordingly, the magnetization direction of the recording layer 11 and the magnetization direction of the reproduction layer 13 are opposite, and the resistance of the magnetoresistive film increases. By changing the magnetization direction of the reproducing layer from the state shown in FIG. 8 to the state shown in FIG. 9, the magnetic resistance of the magnetic memory element 10 increases. By detecting this change in the resistance, the recording layer 11 is detected. The information recorded in the recording layer 11 can be reproduced.

In the above-mentioned reproducing method, the magnetic memory element is not heated by the element heating means before reproducing. this is,
This is because, by selecting the word line 21 and the read bit line 20, a change in the magnetic resistance value of the magnetic memory element at the intersection can be selected and detected, so that it is not affected by adjacent cells. . However, when it is necessary to change only the magnetization direction of the reproducing layer in the selected magnetic memory element, the reproducing layer is heated using element heating means, the coercive force of the reproducing layer is reduced, and the operating magnetic field is reduced. Alternatively, a magnetic field may be applied.

FIGS. 10 and 11 are cross-sectional views for explaining the operation of recording a magnetic memory device of another embodiment according to the present invention. In this embodiment, the magnetic memory elements 30 are arranged in a matrix, as in the embodiment shown in FIG. In this embodiment, the magnetic memory element 3
This embodiment differs from the above embodiment in that the ferromagnetic layer of the zero magnetoresistance effect film is a perpendicular magnetization film.

Referring to FIGS. 10 and 11, a heating bit line 43 extending in the horizontal direction of the matrix is provided on non-magnetic support substrate 44, and a resistance heating layer is provided on heating bit line 43. 42 are provided. Resistance heating layer 42
Is provided with a first read bit line 41 extending in the vertical direction of the matrix. A magnetic memory element is provided on the first read bit line 41. The magnetic memory element includes a recording layer 31, an insulating layer 32, and a reproducing layer 3
3 are laminated. The recording layer 31 and the reproducing layer 33 have a ferromagnetic layer magnetized in the perpendicular direction. On the reproducing layer 33, a second read bit line 40 extending in the horizontal direction of the matrix is provided.

Between the magnetic memory element 30 and an adjacent cell,
Insulating layers 45 and 46 are provided. It is preferable that the insulating layers 45 and 46 electrically insulate the adjacent cells and also thermally insulate the adjacent cells. A word line 50 for applying a magnetic field to the recording layer 31 and the reproducing layer 33 is provided on a side of the insulating layer 46. In the present embodiment, since the recording layer 31 and the reproducing layer 33 are ferromagnetic layers that are magnetized in the vertical direction, the word lines 50 are provided on the sides of the magnetic memory element 30 as described above.

The heating bit line 43, the first read bit line 41, the second read bit line 40, and the word line 5
0 can be formed from Al or the like. Insulating layer 3
₂ , 45 and 46 can be formed from Al ₂ O ₃ or the like. The recording layer 31 can be formed from CoPt or the like, and the reproducing layer 33 can be formed from GdCo or the like.

FIGS. 10 and 11 show the operation when information is recorded in the magnetic memory element constructed as described above. In recording, first, the recording layer 31 of the selected magnetic memory element 30 is used. A first read bit line 41 passing through the selected magnetic memory element 30 to heat
Current flows between the heating bit lines 43 passing through the selected magnetic memory element 30. As a result, the resistance heating layer 42 generates heat at the intersection of the first read bit line 41 and the heating bit line 33, and this heat is transmitted to the recording layer 31,
The recording layer 31 is heated. A magnetic field E generated by applying a current to the word line 50 from the back side to the front side of the drawing is applied to the recording layer 31 having a reduced coercive force due to the heating. The magnetic field E sets the magnetization direction of the recording layer 31 to the direction of “↑”. In this embodiment,
The magnetization direction of the reproducing layer 33 is also set to the direction of “↑” at the same time.

In order to set the magnetization direction of the recording layer 31 to the direction of "↓", as shown in FIG. 11, a current flows between the first read bit line 41 and the heating bit line 43, and In a state where the resistance heating layer 42 generates heat and thereby heats the recording layer 31, a current is applied to the word line 50 from the near side to the far side of the drawing to generate a magnetic field F, and the magnetization of the recording layer 31 is caused by the magnetic field F. Set the direction to “↓”. As described above, information “0” or “1” can be recorded depending on whether the magnetization direction of the recording layer 31 is set in the “↑” direction or the “↓” direction.

FIGS. 12 and 13 are cross-sectional views for explaining the operation when reproducing the recorded information. FIG.
2 and FIG. 13, the recording layer 3 as shown in FIG.
The reproduction method when recording is performed with the magnetization direction of No. 1 set to the direction of “↓”.

As shown in FIG. 12, a current flowing from the near side to the far side of the drawing flows through the word line 50 to generate a magnetic field G. At this time, the amount of current flowing through the word line 50 is adjusted so that the magnetization direction of the recording layer 31 is not changed by the magnetic field G and only the magnetization direction of the reproduction layer 33 is controlled by the magnetic field G. The magnetization direction of the reproducing layer 33 is set in the direction of “↓” by the magnetic field G generated in this manner.

Next, as shown in FIG.
To generate a magnetic field H in the reverse direction.
This magnetic field H is also set to a magnetic field intensity such that only the magnetization direction of the reproducing layer 33 can be controlled. By the magnetic field H, the reproducing layer 3
The magnetization direction of No. 3 is reversed, and is set to the direction of “↑”. Accordingly, the magnetization direction of the reproducing layer 33 and the magnetization direction of the recording layer 31 are opposite, and the magnetic resistance of the magnetic memory element 30 increases.

By flowing a sense current between the first read bit line 41 and the second read bit line 40, a change in resistance value when the state of FIG. 12 changes to the state of FIG. 13 is detected. can do. That is, in the present embodiment, since the magnetoresistance value increases by changing from the state illustrated in FIG. 12 to the state illustrated in FIG. 13, it is possible to detect an increase in the resistance value. As a result, it is detected that the magnetization direction of the recording layer 31 is the direction of “↓”.
Information recorded on the recording layer 31 can be reproduced.

In the reproducing operation shown in FIGS. 12 and 13, the reproducing is performed without heating the reproducing layer 33.
If necessary, the reproducing layer 33 may be heated and reproduced by using element heating means.

In the above embodiment, a magnetic memory element using a coercive force difference type magnetoresistive film has been described. However, the present invention is not limited to this, and other magnetoresistive films such as a spin valve type may be used. Also applies to Also,
Although a tunnel type giant magnetoresistive film having an insulating layer provided between ferromagnetic layers has been described as an example, the present invention is not limited to this.

[0045]

According to the present invention, information can be recorded and reproduced with a small operating magnetic field and with reduced influence on adjacent cells. Therefore, high integration of the magnetic memory element can be achieved, and a nonvolatile solid-state memory device having a large recording capacity can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram for explaining a magnetic memory device of the present invention.

FIG. 2 is a schematic configuration diagram for explaining a magnetic memory device of the present invention.

FIG. 3 is a diagram showing a relationship between coercive force and temperature of a recording layer and a reproducing layer in a magnetic memory element.

FIG. 4 is a plan view showing one embodiment of a magnetic memory device according to the present invention.

FIG. 5 is an enlarged schematic perspective view showing one of the magnetic memory elements shown in FIG. 4;

FIG. 6 is a sectional view for explaining an operation when information is recorded on the magnetic memory element shown in FIG. 5;

FIG. 7 is a sectional view for explaining the operation when information is recorded on the magnetic memory element shown in FIG. 5;

FIG. 8 is a cross-sectional view for explaining an operation when reproducing information recorded in the magnetic memory element shown in FIG. 5;

FIG. 9 is an exemplary cross-sectional view for explaining an operation when reproducing information recorded in the magnetic memory element illustrated in FIG. 5;

FIG. 10 is a cross-sectional view for explaining an operation at the time of recording on a magnetic memory device of another embodiment according to the present invention.

FIG. 11 is a cross-sectional view for explaining an operation when recording on a magnetic memory device of another embodiment according to the present invention.

12 is a cross-sectional view for explaining an operation when reproducing information recorded on the magnetic memory element shown in FIG.

13 is a cross-sectional view for explaining an operation when reproducing information recorded in the magnetic memory element shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Magnetic memory element 2 ... Magnetic field application means 3 ... Element heating means 4 ... Element selection means 10 ... Magnetic memory element 11 ... Recording layer 12 ... Insulating layer 13 ... Reproduction layer 20 ... Read bit line 21 ... Word line 22 ... Resistance heating Layer 23 heating bit line 24 support substrate 25 26 insulating layer 30 magnetic memory element 31 recording layer 32 insulating layer 33 reproducing layer 40 second read bit line 41 first read bit line 42 ... Resistance heating layer 43. Heated bit line 44. Support substrate 45, 46. Insulating layer 50. Word line.

Continued on front page (72) Inventor Takeshi Kato Inside Nagoya University, Furomachi, Chikusa-ku, Nagoya-shi, Aichi Prefecture (72) Inventor ▼ Taka ▲ Naoki 2-5-2-5 Keihanhondori, Moriguchi-shi, Osaka SANYO Electric Co., Ltd. (72) Inventor Toshio Tanuma 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Satoshi Sumi 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Inside the corporation

Claims (5)

[Claims] A magnetic memory element arranged in a matrix; a magnetic field applying means for applying a magnetic field to the magnetic memory element for recording and reproducing information; and a magnetic memory element selected from the magnetic memory elements. Element heating means for heating the magnetic memory element so as to be operable by a magnetic field from the magnetic field applying means. 2. The magnetic memory device according to claim 1, wherein said magnetic memory element is an element having a tunnel type giant magnetoresistive film. 3. The tunnel type giant magnetoresistive film,
3. The magnetic memory device according to claim 2, comprising two perpendicularly magnetized layers and an insulating layer interposed therebetween. 4. A first heating current line and a second heating current line which are arranged along a matrix of the magnetic memory elements and extend so as to intersect on each magnetic memory element. The magnetic memory device according to claim 1, further comprising: a resistance heating layer provided so as to be sandwiched between an intersection of the first heating current line and the second heating current line. 5. The magnetic memory device according to claim 1, wherein a magnetic field application area by said magnetic field application means is wider than a heating area by said element heating means.