JPS59151374A - Magnetic storage element - Google Patents

Abstract

PURPOSE:To improve the limit of high density based on a characteristic of a bubble holding layer by using pairs of adjacent vertical Bloch lines formed in a Bloch magnetic wall around a stripe domain existing in a ferromagnetic thin film as a storage information unit. CONSTITUTION:Information written by a generator 4 moves a write major line from upper to lower direction. In order to store this information to a minor loop 5, the minor loop is constituted by the Bloch magnetic wall holding a vertical Bloch line VBL so as to transfer the information on the major line represented by the presence or absence of the bubble 6 to the minor loop in the form of the VBL. The information transferred to the minor loop by a write line transfer gate 7 is moved on a stripe domain magnetic wall constituting the minor loop and the information transfer from the minor loop to a read major line is attended with the conversion of the bubble from the VBL. A read transfer gate 8 has a block replicator function also.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to vertical Proch lines that exist statically and stably within Bloch domain walls that form the boundaries of striped domains formed in a ferromagnetic thin film whose easy magnetization direction is perpendicular to the film surface. The present invention relates to a novel magnetic memory element using as a memory unit.

The development of magnetic bubble elements is actively being carried out in various places with the aim of increasing density, including permalloy devices, ion-implanted contiguous disk devices, current-driven devices, and so-called hybrid devices that combine these devices. It has been said that the limit to the high density of these devices lies in the photolithography technology used to form the bubble transfer path.

However, in recent years, the technology has advanced rapidly.

As a result, the issue of materials for increasing density, that is, to what extent the bubble diameter can be reduced, has become a problem. With the currently used garnet materials, the minimum attainable bubble diameter is said to be 0.3 μm. Therefore, a bubble material that retains bubbles with a diameter of 0.3 μm or less must be found other than garnet material. This is not easy and is even considered to be the limit of bubble density.

It is an object of the present invention to provide a memory element that can significantly improve the density limit based on the characteristics of the bubble retaining layer and that can maintain information readout time at the same level as conventional elements. do. That is, the magnetic memory element of the present invention is a magnetic memory element comprising an information reading means, an information writing means (2), an information storage means, and a ferromagnetic film (ferromagnetic film) whose easy magnetization direction is perpendicular to the film surface. A pair of adjacent perpendicular Protubo lines formed in a Bloch domain wall around a stripe domain existing in a magnetic film (including a magnetic film) is used as a storage information unit, and the method has means for transferring the vertical Proch lines within the Bloch domain wall. It is characterized by

Hereinafter, the present invention will be explained in detail based on examples thereof. The main point of the present invention is that the perpendicular Bloch line existing in the Bloch domain wall that forms the vicinity of the stripe domain existing in the perpendicular magnetization film is used as the information storage unit. One form of vertical Plochline memory will be described as an example. In this example, the major line uses bubble domains as information units as before, and the minor loop consists of strike domains,
Vertical Bloch lines (hereinafter referred to as VBL) that exist within the Bloch domain wall around the Bloch domain wall will be described as information units. Figure 1 is a diagram of the entire chip (3). To show the overall information flow, first, Generator 1
The information written in (presence or absence of a bubble) moves the writing major line from 1hi to below. In order to store this information in minor loop 2, change the minor loop to VB so that the information on the major line indicated by the presence or absence of bubble 3 can be transferred to the minor loop in the form of VBL.
The feature of the present invention is that it is constructed with a Bloch domain wall that can hold L, and is an important key to the dramatic improvement in memory field. The information transferred to the minor loop by the write line transfer gate 4 (VB
T,) can move the striped domain domain wall that constitutes the minor loop. Information transfer from the minor loop to the bladder major line is V B
Involves conversion from L to bubble. Note that this read transfer gate 5 also has a block rebuild function.

In this way, by configuring the minor loop with striped domains existing in the bubble material and using (4) VI3T instead of the bubble domain as the information unit on the minor loop, it is possible to create a device using conventional bubble domains. In comparison, an improvement in storage density of about two orders of magnitude can be achieved.

The operation of each part of the chip will be described in detail below.

In this embodiment, the current drive method (DCP) is used for both writing and reading of the major line. This is because in the conventional in-plane rotating magnetic field drive method, there is a high risk that stored information will be destroyed due to the interaction between the in-plane magnetic field and the IL on the minor loop.

Further, the write transfer gate exemplified below uses interaction between a bubble on the major line and a strike domain head forming a minor loop. In other words, when there is a bubble domain on the major line, the heads of the strike domains that make up the minor loop connected to it move away from the bubble due to the repulsive interaction between the bubble and the strike domain.

FIG. 2 shows the operating procedure of a so-called complementary transfer gate in which V B T is applied to the strike domain domain wall of the minor loop when there is no bubble in the write major line (5). The transfer gate is made up of four parallel conductors - 6, 7, 8 and 9. If there is no bubble on the major line, the strike domain forming the minor loop is stabilized at the position shown in FIG. 2(a).

As a method of creating V l-3L in the stripe domain head, a method is used in which a pulse current is applied to the conductor line q and the stripe domain head is dynamically moved in the direction shown in FIG. 2(b). This process is called dynamic conversion of the Stoibherer domain wall structure.

By doing this, on both sides of the striped domain head, there are places 1 where the magnetization of the Bloch domain walls collide with each other.
．． 1, 1.2 can be done. That part is called VBJ. When VBL is created using the method just described, ■VBL], 1 and 0VBL12 are always paired (6
) has become. ■If VBT and 0VBL exist next to each other, they are likely to recombine with each other, resulting in poor information stability. Figure 2(b) shows the external in-plane magnetic field peak. By adding , the Bloch domain wall magnetization in the striped domain head part is fixed in the Hjp direction;
This prevents ■VIAL and ○VBL from recombining. However, in actual devices, it has been found that it is inappropriate to always add ζHl from the viewpoint of stability of VTIL information. Therefore, we devised a way to make the VBL quizzes into one type so that VT3L Senho can be stabilized even without Hip.

At that time, it was decided to leave ○VBL in consideration of the fact that the read line transfer gate could have a replicator function. Next, a method of leaving only □VBL on the striped domain domain wall of the minor loop will be described. First, the second
Add H and ip in the direction shown in figure (d). Then,
Since Zeeman energy is obtained by directing the Bloch domain wall magnetization toward the Hip, ■VBT comes to the striped domain head.

In this state, pulse current ■2? flows through conductors 8 and 9 in opposite directions (7). The stripe domain head is separated as shown in FIG. 2(e). Then, ■VBL
The striped domain head with □V
BL 13 will be formed. This 0V BL, L, ○V left in the minor loop) JT, 42, a total of two 0V
BL are paired to form bits. Through this series of operations, the information "'0" on the write major line could be transferred into the minor loop as a pair 14 of ○V B , I. VBLs of the same sign remain stable even if they approach each other. If the minor loose stripe domain head corresponding to where the bubble exists on the major line is placed on the right side of conductor 9 using repulsive interaction with the bubble, the series shown in Figure 2 will be created. In operation, the striped domain head state is unchanged.

Therefore, as a result, the information "1" of the major line is transferred in a state in which there is no VBL pair in the minor loop. Note that the unnecessary bubbles cut out by the transfer gate are as shown in Figure 2(f)l.
Apply parallel pulses (8) to conductors 6 and 8, move them to the major line, and finally erase them. In the minor loop, information is stored as shown in FIG. 3, with each ○VBL pair as one bit. ■, (
h, ■, . . . each correspond to one bit. Third
The figure shows an information string in which all bits are corrupted.

Next (bit period in this minor loop, that is, V B
L Consider how the spacing is given. The interaction between the two rules [1] is the magnetostatic energy generated by the magnetic pole induced at the location of VBL, and the exchange interaction due to the twisting of magnetization within the domain wall. The former is VBT,
The latter generates a force that tends to shorten the distance between the two, and the latter generates a force that forces VBL to avoid its comrades. From the balance of these two forces, the stable distance So between the two VDTs is SO−πΔ when the Q value (5HK/, iπM8) of the bubble material is large.
Totoru. Here, Δ-(A/2πMs). This S
o is approximately equal to the characteristic length l of the bubble material. Therefore, bit period 28o=21! ,'- becomes. The density of VT3I is μm bubble material. In a 5.1 cm2 chip, the number of stripe domains is 5,000, that is, the number of domain walls is (9) 10,000. l! = 0.125 μm, the interval (bit period) between the V I-3L pair is 21=0
．． 25 μm, and 4×1 VBL pairs are included in the domain wall within the length of 1 crrL. Therefore, 4 x 104 x 104:400 megabits can be accommodated in lCm2. When VBL exists at high density and at equal intervals, VB
The distance between L pairs is S. stabilized by However, if VBL pairs exist discontinuously, for example, 00101000
Considering an information string such as ``1-...'', transfer pattern 15 is added so that one bit can be sequentially transferred, and 785
The bit position was determined using the attractive force Fa and repulsive force Fr between the two.

Here, as an example, the striped domain constituting the minor loop has a width S with a period of 2So in the direction perpendicular to the longitudinal direction of the striped domain. We formed a pattern of parallel thin wires made of permalloy thin film, and utilized the interaction between the magnetic poles and VBL induced on both sides of the parallel thin wires.

Transfer along the minor loop of VBL was performed dynamically by applying a pulsed bias magnetic field to the stripe domain. The velocity y, 11, of VBL(10) is the velocity component in the normal direction to the domain wall surface of the domain wall.
Using ' ``y+t, = (πQy2/2a)- can be written.

Since the interval (bit period) between the VBL pair is 2πA, V
Pulse magnetic field vibration @H and 1(l) to move BL by 2πA
If n5ec exists, it means that VBL can move by 2πA. Here, the value of a portion where VBL is densely packed at intervals of πA is used as Pw. Other parts can move faster. In other words, the area where VBL is densely packed is about 1/1000 of the area where there is no VBL at all. However, this is VBT,
had no significant effect on sequential transfer.

The read transfer gate is a replicator that converts the information stored as VBL in the striped domain domain wall forming the minor loop into a bubble and transfers it to the major line, and also prevents the information on the minor loop from being destroyed. It also has the functions of The principle of operation will be explained step by step in FIG. 4 (11). First, Figure 4 (
As shown in a), one bit formed by the VBL pair is fixed to the stripe domain head by applying, for example, an in-plane magnetic field Hip. Next, as shown in FIG. 4(b), pulse currents p4 are applied to the conductors 16 and 17 in opposite directions to cut the stripe domains and create bubbles. Then, the stripe domain head after cutting out the bubble (this is the same VBT as the VBL cut out as shown in FIG. 4(d)).

is regenerated. Such a VBL replication effect occurs only for VBL with a minus sign.

In order to take advantage of this characteristic, this device does not use a positive VBL to store minor loose information, but instead applies a ma-line current pulse ■p meter to transfer the information to the major line.

The bubble is then transferred along the major line to the detector 19.

When a current pulse is applied to the conductors 20 and 21 shown in Fig. 5 to cut out the bubble, the pulse amplitude is as shown in Fig. 5 (12). As shown in )), this gate uses a different L depending on the case where VBL is present. The reason for this will be briefly explained. As shown in FIG. 6, the direction of magnetization in the stripe domain domain walls (Bloch domain wall portions) on both sides of the stripe domain head differs by ζ between the case where the stripe domain head does not have a negative VBL and the case where it does have a negative VBL. That is, when looking at the twisting of magnetization from the direction perpendicular to the domain wall surface of the striped domain, in the case of FIG. 6(a) without VBL, the magnetization is twisted completely once when crossing the striped domain. In contrast, in the case of FIG. 6(b) with VBL, the magnetization is twisted by a half turn only within the domain.In this case, as the stripe domain width is narrowed, the exchange between the magnetizations becomes Due to the increased effect, the reversal magnetization of the domain part is rotated in the same direction as both sides of the domain, i.e., by eliminating the domain, an increase in exchange energy is avoided.

On the other hand, in the case of Fig. 6(a), the magnetization makes one revolution by passing through the domain part, so the increase in exchange interaction when the width of the domain (13) is narrowed is shown in Fig. 6(b).
This cannot be avoided using the mechanism shown in . Instead, the exchange energy is prevented from increasing by not reducing the domain width. In this way, the mechanism for avoiding the increase in exchange interaction during the process of narrowing the stripe domain width is different depending on whether the stripe domain head has a VBL or not.

Figure 7 shows a comparison of the vanishing magnetic field of the stripe domain formed in the 57zm bubble material for the domain wall structures of Figures 6(a) and (b), and the Figure 6 shown in Figure 7(b). (b) It shows that a considerable number of cases are likely to disappear. Taking advantage of this difference in mechanism, as shown in Figure 5, when a pulse current p4 is applied to conductor 2 (1, 21) to divide the stripe domain, if there is no VBL in the stripe domain head, Figure 6 (a
), it is difficult to divide as shown in FIG. 5(a). On the other hand, if there is a VBL, it is likely to be separated as shown in FIG. 5(1), which corresponds to FIG. 6(b). Utilizing such an operation, a bubble element is formed in which the VBL enters the main (14) inner loop at a position where there is no bubble on the write line, and sends out the bubble to the read line.

In addition, there is a negative VHL on the striped domain head.
If the stripe domain head part is divided, the original V
r(L) is reproduced because I-Tip is added. If Hip is not added, the in-plane component of the bubble magnetic field will necessarily result in a negative VBL.
is no longer guaranteed to be played.

Next, a method of eliminating the V13L pair will be explained.

As shown in FIG. 8(a), bring the VI3T pair you want to erase, the V 13 L pair you want to erase in the minor loop on the major line side, and the VBT pair next to it, to the stripe domain head, and write the information. When writing, in order to cut off the positive V B T (15), the striped domain head has the V
The VBL that has been trapped together with the BL pair will be replicated. In the end, only the VBL pair that is desired to be erased will be erased.

In addition, if you want to clear the entire minor loop, in advance,
After all the stripe domains are erased by increasing the bias magnetic field, a minor loop drive domain is formed from the S=1 bubble, thereby creating a state in which the VBL has no heat and all pits are zero.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of an element chip according to the present invention. FIG. 2 is a structural diagram of one embodiment of the write transfer gate of the present invention. FIG. 3 is a block diagram I of an embodiment of the minor loop of the present invention.
FIG. 12 is a diagram showing the results of comparing the appearance of domain walls (16) in striped domains without VBL and domains with VBL in cases where the striped domain head does not have VBL and with cases in which VBL exists. In each Figure 8, ■ is a generator, 2 is a minor loop, 3 is a bubble,
4 is a write line transfer gate, 5 is a read transfer gate, 6°7.8, 9 is a conductor-1
10 is a stripe head part, 11 , 12 , 13 are vertical Ploch lines, 14 is a pair of vertical Ploch lines, 1
5 is a transfer pattern; 1. fi, 1.7° 18 is the conductor, 2Q, 21 is the conductor -8 (17) Figure 4 No. 7 ■ C-strive domain car\Ha'Aldo back. × Fire extinguisher 1ro. △ Stra 4 Bud Domain Mac\"GA 1-RO. Figure 8 Procedural Amendment Import) 1. Indication of the case 1982 Patent Application No. 18234
6 No. 2, Name of the invention Magnetic storage method and magnetic storage element 3, Relationship to the case of the person making the amendment Applicant No. 33-1 (423), Shiba-go-cho, Minato-ku, Tokyo NEC Corporation Representative Tadahiro Sekimoto 4. Agent address: Sumitomo Sanda Building, 37-8 Shiba 5-chome, Minato-ku, Tokyo 108 (contact address: NEC Corporation Patent Department) 5. Number of inventions increased by seconds due to amendment 16. Full text of the description and drawings in the title of the invention in the application to be amended 7. Contents of the amendment (]) "Magnetic memory element" in the title of the invention in the application has been changed to "magnetic memory method and magnetic memory element." and correct it. (2) The description and drawings shall be amended as attached. Description Title of the invention Magnetic storage method and magnetic storage element Claims (z) In a magnetic storage element comprising an information reading means, an information writing means, and an information storage means, the direction perpendicular to the film surface is the easy magnetization direction. 2 adjacent adjacent Bloch domain walls created in the Bloch domain wall around the stripe domain existing in the ferromagnetic film.
Permalloy devices, ion-implanted continuous disk devices, current-driven devices, and devices that use a vertical Proch line pair consisting of two vertical Proch lines as a storage information unit and have means for transferring the vertical Proch lines within a Bloch domain wall are described in each item. So-called hybrid devices, which are a combination of the two, are being actively developed. It has been said that the limit of increasing the density of these devices lies in the photolithography technology used to form the bubble transfer path. However, in recent years, this technology has advanced significantly. As a result, the issue of materials for increasing density, that is, to what extent the bubble diameter can be reduced, has become a problem. In the currently used garnet materials, the minimum bubble diameter that can be reached is said to be 0.3 μm. Therefore, a bubble material that retains bubbles with a diameter of 0.3 μm or less must be found other than garnet material. This is not easy and is even considered to be the limit of bubble density. The present invention is based on the characteristics of the bubble retaining layer, and provides a magnetic storage method and a magnetic storage method that can significantly improve the densification limit and keep the information read time at the same level as conventional devices. The purpose is to present the elements. That is, the present invention is a magnetic storage method having the functions of reading, writing, and storing information, which uses a ferromagnetic film (including a ferrimagnetic film) whose easy magnetization direction is perpendicular to the film surface.
A magnetic storage method characterized in that a vertical Ploch line pair consisting of two adjacent perpendicular Ploch lines formed in a Bloch domain wall around a striped domain existing in a stripe domain is used as a storage information unit, and the vertical Ploch line pair is used as a storage information unit. This is a magnetic memory element characterized by using a means for transferring the perpendicular Bloch line within a Bloch domain wall. FIG. 1 shows a pair of vertical Bloch lines formed within a Bloch domain wall. Vertical Proch line 2 is a Bloch domain wall] A Neel-shaped magnetic field formed where the counterclockwise Bloch domain wall (Figure 1 (1)) and the clockwise Bloch domain wall (Figure 1 (C)) collide. 4- Wall part (2 in Fig. 1(a)). By using this pair of vertical Proch lines as a unit of storage information, it is possible to achieve a significant increase in recording density compared to conventional magnetic bubble elements. The method of the present invention and the "-μ embodiment" of a magnetic memory element operated according to the method will be described in detail below. The perpendicular Bloch line that exists within the Bloch domain wall is used as the information storage unit,
In the following embodiment, the vertical/rotcho line memory 〇- format will be described using a major/minor configuration as an example. In other words, on the major line (conventionally, the bubble domain is the information unit, and the minor loop is composed of the stripe domain,
FIG. 2 is an overall view of the chip, which describes the information unit of the vertical Proch line (hereinafter referred to as VBL) existing within the peripheral Protubo domain wall. To show the overall flow of information, first, the information written by the generator 4 (the presence or absence of bubbles) moves down the writing major line from ``;''. In order to store this information in the minor loop 5, a bloch that can hold the minor loop VBL is used so that the information on the major line indicated by the presence or absence of the bubble 6 can be transferred to the minor loop in the form of V RT. The feature of the present invention is that it is composed of domain walls, and is an important key to dramatically improving storage capacity. The information (VBT) transferred to the minor loop by the write line transfer gate 7 can be moved on the stripe domain magnetic wall forming the minor loop. Information transfer from the minor loop to the read major line involves conversion from VBL to bubble. Note that this read transfer gate 8 also has a block replicator function. In this way, by replacing the minor loop with the stripe domain existing in the bubble material and using VBL instead of the bubble domain as the information unit in the "minor loop", we are able to improve the Approximately two orders of magnitude improvement in storage density can be achieved. Hereinafter, the operation of each part constituting the magnetic memory element described in "2" will be explained in detail. In this embodiment, the current drive method (DCP) is used for both writing and reading of the major line. This is because in the drive method using the in-plane rotating magnetic field that has been commonly used in the past, there is a high risk that stored information will be destroyed due to the interaction between the in-plane magnetic field and the minor loop VI3L. Further, the write transfer gate shown in the following example uses the interaction between the bubble on the major line and the striped domain head forming the minor loop. In other words, when there is a bubble domain on the major line, the heads of the stripe domains forming the minor loop connected to it move away from the bubble due to the repulsive interaction between the bubble and the stripe domain. Figure 3 shows the operating procedure of a so-called complementary transfer gate, which writes VBT to a minor loose stripe domain domain wall when there is no bubble 7 on the write major line. The transfer gate is made up of four parallel conductors -9°+0, 11, 1.2. If there is no bubble on the major line, the striped domain that makes up the minor loop is as shown in Figure 3 (a).
Stabilize it in the position shown. As a method of creating a VBL on a striped domain head, here we will use a conductor.
A method is used in which a pulse current 1 is applied to the line 10 and the striped domain head is dynamically moved in the direction shown by K in FIG. 3(b). By doing this, the magnetization of the Bloch domain wall part of the stripe head part 13 becomes 1800
Rotate from the direction shown in Fig. 3(a) to Fig. 3(b), (
Change direction to c). This is called dynamic conversion of domain wall structure. By doing this, areas 14 and 15 are formed on both sides of the striped domain head where the magnetizations of the Bloch domain walls collide with each other. That part is VR
It is called L. If V 11 T- is made using the method described in 8- above, ΦVBL will always be obtained.
1.4 toeVBL15 force vs. K! Tsutail. eVB
When L and OVT"L exist next to each other, they tend to recombine with each other, resulting in poor information retention stability. Figure 3 (b) shows the external in-plane magnetic field.

[11. By adding
Prevents BL recombination. However, in actual devices, it has been found that it is inappropriate to always add HIp from the viewpoint of V B T and information stability. Therefore,
Here, we devised an idea to use only one type of Vr3L so that the VBT information could be stabilized even without 1jHi. At that time, considering that the readout line transfer gate can have a replicator function, eV B
T. I decided to leave it. Next, a method of leaving only QVBL on the striped domain domain wall of the minor loop will be described. First, add Fl 1 p in the direction shown in FIG. 3(d). Then, since Zeeman energy is obtained by directing the Bloch domain wall magnetization toward the Hip direction, ■V B T comes to the striped domain head. In this state, pulse current ■0.
, and the stripe domain head is shown in Figure 3(e) ↓
Separate the sea urchins. Then, eVBL 1 G is formed in the stripe domain head from which eVBL has been cut. This eVBT was left in a minor loose e
A total of two (9VBT) of VBL12 are paired to form a bit. Through this series of operations, information "O" on the write major line was transferred as pair 17 of KI9VBL in the minor loop.VBL of the same sign exist stably even if they approach each other.The minor loop strike domain head corresponding to the bubble on the major line utilizes the repulsive interaction with the bubble to move the right side of Kongkuku 12 +
If C< is set, the state of the striped domain head remains unchanged in the series of operations shown in FIG. Therefore, as a result, the information "1" of the major line is transferred with no VI3L pair in the minor loop. Incidentally, as shown in FIG. 3(f), the unnecessary bubble cut off by the transfer gate is moved to the major line by applying a parallel pulse voltage to the conductors 9 and 11, and finally erased. In the minor loop, information is stored as shown in FIG. 4 by concatenating pairs of QVBT and L bits. ■, ■, ■, . . . each correspond to one bit. @4 Figure shows the information string in which all bits have been written. Next, the bit period in the minor loop is 13V B T,
Consider how the spacing is given. two v
BXJ17) interactions include magnetostatic energy generated by magnetic poles induced at the VFIL location and exchange interactions due to twisting of magnetization within the domain wall. The former is V
A force is generated in the direction that reduces the distance between B and T, and the latter, in turn,
BT develops the power to avoid comrades. From the balance of these two forces, the stable distance So between the two V BL can be set as So - πΔ if the Q value (= IIk/4tcMs) of the bubble interest is dominated. Here, 4=(A/2π
Ms'). 11- approximately equal to the characteristic length t of this SO bubble material. Therefore, the bit period 28o=27. The density of VBT is 1 μm. When bubble material is used, the number of stripe domains in 1efA chi-nobu is 5,000, that is, the number of domain walls is 10,000. o t = 0.125 μm
Then, the interval (bit period) between the Vr3L pair is 21=0
25 μm, and V B L in the domain wall within the length of 1-
Pair 4X1. Holds O' pieces. Therefore, 1-4 in
X 10'X 10' = 400 megabits can be accommodated. When VBL exists at high density and at equal intervals, VBL
The pair spacing is stabilized with SO. However, VBT,
If the pairs exist discontinuously, for example, @00101
Considering an information string such as "0001...", a transfer pattern 18 is added so that one bit can be sequentially transferred.
The bit position was determined using the attractive force Fa and repulsive force Fr between VBL. Here, as an example, a parallel thin line pattern made of a @SO permalloy thin film is formed with a 2So period in the direction perpendicular to the longitudinal direction of the stripe domain on the stripe domain constituting the minor loop, and
- Utilizing the interaction between the magnetic poles induced on both sides of the thin line and VBL. As one method, the transfer along the minor loop of V B L was performed dynamically by applying a pulsed bias magnetic field to the stripe domain in the direction perpendicular to the ferromagnetic film. The velocity νBTJ of V B T is calculated by using the velocity component vw of the domain wall normal to the domain wall surface, vBL-(gQ″A/2α)v
Lol! : I can write. VBT pair interval (hit period) is 2
Since it is πA, the pulse magnetic field amplitude [I and width T to move V B T by 2πA is HT = 25oe, and if the width is 10 nsec, then vBL minus 2πA
It means that you can move. Here, as vW, the value of a portion where VBL is densely packed at intervals of πΔ is used. Other parts: You can move faster with your feet on. In other words, vw a
The part where VllTi is densely packed and VBT,
is about t/1ooOK1 compared to the part where you don't want one. However, it had no effect on the sequential transfer of Koreke VBL. A readout transfer gate consisting of three combination lids converts the information stored as V B T in the stripe domain domain wall forming the minor loop into a bubble and transfers it to the major line.
It also functions as a replicator to prevent information on the minor loop from being destroyed. The principle of operation will be explained step by step in FIG. First, as shown in FIG. 5(a), one bit formed by a VBL pair is fixed to a stripe domain head by applying, for example, an in-plane magnetic field H1p. Next, as shown in FIG. 5 0)), the pulse current T, 4
and cut the striped domain to create a bubble. Then, after cutting out the bubble, the striped domain head has the cut VDT as shown in Fig. 5(d).
. The same vBTJ is regenerated. V B L like this
The replication effect occurs only for VBL with a minus sign. In order to utilize this characteristic, this device does not use positive V B II to store information in the minor loop, but uses negative V 131. is using. The bubble cut out from the minor loop is shown in Figure 5 (C).
Apply parallel current lTl5 to Kongkuku 20.21 and transfer it to the major line as shown below. The bubble is then transferred along the major line to the detector 22. When a current pulse is applied to the conductors 23 and 24 shown in Fig. 6 to cut off the bubble, the pulse amplitude is as shown in Fig. 6(a).
As shown in FIG. 6(b), there is no VBL in the stripe head, and as shown in FIG. 6(b), there is VI3T. There are different things that can be used at this gate. The reason for this will be briefly explained. When the striped domain head does not have a negative VBL and when it does,
Stripe domain domain walls on both sides (protubular domain walls)
As shown in FIG. Toe 9,
Looking at the twist of magnetization from the direction perpendicular to the domain wall surface of the striped domain, we see that it is VDT, but in the case of Figure 7(a),
The magnetization is twisted one complete time as it traverses the stripe domain. On the other hand, in the case of FIG. 7(i) where \rBL is 15-, the magnetization is twisted by half a turn only within the domain. In this case, as the stripe domain width is narrowed, the exchange interaction between magnetizations increases, so that the reversed magnetization of the domain portion is rotated in the same direction as both sides of the domain. In other words, the increase in exchange energy is avoided by eliminating domains. On the other hand,
@ In the case of Figure 7 (a), the magnetization makes one revolution by passing through the domain part, so the mechanism shown in Figure 7 (b) avoids the increase in exchange interaction when the domain drift is narrowed. Can not. Instead, by setting K so as not to reduce the domain width, exchange energy is prevented from being overwritten. Therefore, the mechanism for avoiding an increase in exchange interaction during the process of narrowing the stripe domain width differs depending on whether the stripe domain head has a VBTJ or not. Figure 8 shows the results of comparing the vanishing magnetic field of a stripe domain formed in a 5 μm bubble material with respect to the domain wall structure of Figures 7 (a) and (1)), and Figure 8 (b) K
This shows that the case corresponding to FIG. 7(b) is unlikely to disappear. Taking advantage of this difference in mechanism, as shown in Figure 6, if you try to divide the stripe domain by applying Harusumi flow ■r+4 to the conductor 23°24, the stripe domain head will have a VRT, and if there is no VRT, then the rod 7 Since it corresponds to figure (a), it is difficult to divide it as shown in figure 6 (a).On the other hand, if VBT is Utilizing this operation, a bubble element is formed in which the VRT enters a minor looseness at a position where there is no bubble on the write line and sends out a bubble to the read line. In addition, negative V D to Rad to the striped domain
This is because when T is present, when the striped domain head section is divided, the same VRT as the original VRT is reproduced in the newly created striped domain head, but Hip is added. If l1ip is not added, negative VBL will not necessarily be reproduced due to the in-plane component of the bubble magnetic field. Next, the elimination method for VIH pairs will be explained. The V' B L pair to be erased is placed at the closest position to the minor loose stripe domain head on the writing major line side, as shown in FIG. 9(a). Next, Figure 9(b)
And as shown in (C), apply an in-plane magnetic field 1-1 i p, bring the VBL pair to be erased and one half of the VF3L pair next to it to the stripe domain head, and when writing information, apply a positive VI3L. Cut out the striped domain head using the parallel conductor used to cut out the striped domain head. Then, as shown in FIG. 9(d), the VBL brought along with the VT3L pair to be erased is replicated to the striped domain head after the bubble domain has been cut out. In the end, only the VBL pair that is desired to be erased will be erased. In addition, if you want to clear the entire minor loop, in advance,
After once erasing all the stripe domains by increasing the bias magnetic field, a minor loop drive domain is formed from 5==1 bubbles, thereby creating a state in which the VBL has no heat and all pits are zero. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 2 is a diagram showing a vertical Bloch line in a Bloch domain wall used as a storage information unit in the present invention, and Fig. 2 is an overall diagram showing an embodiment of an insect storage element operated by the method pressure of the present invention. Goeki's configuration diagram, Figure 3 is a structural diagram of an embodiment of the write transfer gate, 4th (K2I is the configuration l of an embodiment of the minor loop), and Figure 5 is a structural diagram of an embodiment of the read transfer gate. , Fig. 6, Fig. 1°C is a domain wall structure diagram of a striped domain without vBL in the stripe domain and a domain with vBL, Fig. 8
Figure 9 is a diagram showing the results of a comparison of stripe domain disappearance between the cases where the stripe domain head does not have VBT and the case where VBT does exist. FIG. 9 is a structural diagram of an embodiment of the Bloch-in disappearance method. In each figure, 1 is the Bloch domain wall, 2 is the vertical Bloch line, 3 is the direction of magnetization within the domain wall, 4 is the generator, and 5 +d
Minor loop, 6 is bubble, 7 is write 19-in line transfer gate, 8-digit output transfer gate, 9, 10, 11.12 is conductor-5
13 stripe head section, 14, 15.16 are vertical Proch lines, 17 vertical Protubo line pairs, 18 are transfer patterns, 1.9, 20.21 are conductors, 22 are detectors, 23.2/l conductors -020- Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 87 Figure 8 Figure 0 It does not disappear. After completing the Ostra, it will be either a domain or a bafunre. Figure 9 5. Amendment to the procedure to be amended Showa year, month, day ■ ['' Director General of the Patent Office, 1, Indication of the case, 1982, Patent Application No. 182346, 2, Title of the invention, Magnetic storage method and magnetic storage element, 3, Person making the amendment Relationship to the incident Applicant: 33-1 Shiba 5-chome, Minato-ku, Tokyo (423) NEC Corporation Representative: Tadahiro Sekimoto 4, Agent: Sumitomo Mita, 37-8 Shiba 5-chome, Minato-ku, Tokyo 108 "If it's a building n5ec," he corrected. Detailed explanation of the invention in the specification Column Drawing 6 Contents of amendment 1) In the 5th line of the 3rd page of the specification of the written procedural amendment dated November 2511, 1989 IJ, "Each item" has been replaced with "Each place". ” he corrected. 2) In the 3rd negative 15th line of Kaimei M11, the phrase "reachable" is corrected to "reachable." 3) 1 Conventional magnetic bubble element on page 5, line 3 of the same specification.
1 is corrected to read "conventional magnetic bubble element." 4) In the same specification ■) In the third line of page 13, the phrase ``Transfer along the minor loose'' is corrected to ``Transfer along the minor loop.'' 5) In the fourth line of page 13 of the same specification, the phrase "on the ferromagnetic film" is corrected to "on the surface of the ferromagnetic film." 6) On page 13, lines 12 and 13 of the same specification, “The width 1
If the width is 101-7), page 15, line 20 of the same specification, K, ``It is twisted one complete turn.'' is replaced with ``If the width is 101-7. ” I corrected myself. 8) In the 1st and 2nd lines of page 16 of the same specification, the statement ``The magnetization was twisted by a half turn only within the domain'' was corrected to ``The magnetization was twisted 90'' only within the domain.'' 9) On page 16, line 9 of the same specification, ``Magnetization rotates once.''
The statement is corrected by saying, ``Magnetization rotates completely by half a rotation.'' 10) "Runoha Htp" on page 17, line 17 of the same specification
. . .'' to the end of page 17 is changed to ``Ru.'' and ``Noha T-hp . . .'' is deleted. 11) Same specification ■ ``Ploch line vanishing method'' on page 19, fs, line 6, is 1 Proch line elimination method.''
and correct it. 12) Figures 4 and 9 of the attached drawings of the procedural amendment dated November 25, 1980 are attached to attached drawings 2-75 and 79, respectively. Year Patent Application No. 1823
No. 46 No. 2, Title of the invention: Magnetic storage method and magnetic storage cable 3, Relationship to the amended person's case Applicant: Tokyo; 5-33-1 Shiba, Iwa-ku (423) NEC Corporation Representative: Sekimoto Tadahiro 4, agent (3 yen jointly owned by NEC Co., Ltd. Patent Department) 5, amendment order 1-1 attached February 28, 1980 (shipment date) 6 Target of amendment Submitted on January 17, 1980 "Object of amendment" column of written amendment and "Contents of amendment" column 7, "Contents of amendment (1) As shown in the attached sheet (2) Inner boundaries of amendment" column (12) "K r Figure 4 of the attached drawings" I interpret it as "Figure 5 of the attached drawings." Procedural amendment 59.1.17 Month, 1980 Commissioner of the Japan Patent Office Indication of 1, ', 4j 1981 Patent Application No. 1
82346 No. 2, Name of Magnetic Storage Method and Magnetic Storage Element 3, Relationship with the Amendment Person Case Source: 1133-1 (423) Shiba IL-cho, Minato-ku, Tokyo NEC Corporation Representative Tadahiro Sekimoto 4. Agent (contact information [-1 Hondenki Co., Ltd. Patent Department) Drawing 489-

Claims (1)

[Claims] In a magnetic memory element comprising an information reading means, an information writing means, and an information storage means, in a Bloch domain wall around a stripe domain existing in a ferromagnetic film whose easy magnetization direction is perpendicular to the film surface. A magnetic memory element characterized in that it uses the created pair of adjacent vertical Ploch lines as a storage information unit and has means for transferring the vertical Ploch lines within a Bloch domain wall.