JPH0646501B2 - Magnetic bubble memory device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic bubble memory device, and more particularly, to a pattern structure of a magnetic bubble transfer pattern arranged close to a forward 180 degree turn corner pattern of a folded minor loop. It is a thing.

[Background of the Invention]

FIG. 1 shows one minor loop forming a memory area of a magnetic bubble memory element, and a plurality of minor loops of this kind are arranged in parallel in the memory area of the magnetic bubble memory element. . In the same figure, the magnetic bubble transfer path is simplified and shown by a solid line, and the arrow P direction indicates the transfer direction of the magnetic bubble. Such a minor loop is composed of a closed loop transfer path as shown in FIG. As the shape of this closed-loop transfer path, the simple loop type minor loop 1 shown in Fig. 2 (2) to the folding shown in Figs. Overlapping minor loops 2, 3 and 4 have become popular. The first shape of this folded loop
There are various types other than those shown in Figures (b), (c), and (d). An example of such a folded minor loop is, for example, IEEE Trans. MAG-15. No.6, P1691 ~ P1696
Is disclosed in.

The basic element patterns of the permalloy type transfer path that constitutes such a minor loop are as follows: the asymmetric chevron pattern 5 shown in FIG. 2 (a), the half disk pattern 6 shown in FIG. 2 (b), and the same figure (c). The C pattern 7 shown or the club foot pattern 8 shown in FIG.

In the minor loop configured as described above, as shown by the dotted circles in FIG. 1, turn corners for making the transfer direction P of the magnetic bubbles reverse are provided respectively, and these turn corners are provided. Has a forward 180 degree turn corner portion a and a reverse 180 degree turn corner portion b shown in the figure.

FIG. 3 is a main part enlarged pattern plan view showing an example of the above-mentioned forward 180-degree turn corner a part. In the figure, 10a,
10b, 10c, 10d are magnetic bubble transfer paths forming one folded minor loop, 11 is a first basic transfer pattern forming transfer paths 10a, 10b, 10c, 10d, 12 is a forward 180 degree turn corner pattern , 13 and 14 are second and third basic transfer patterns for connecting the first basic transfer pattern 11 and the forward 180-degree turn corner pattern 12, and 15 is the third basic pattern 14 and the forward 180-degree turn corner. A short bar pattern for connecting the pattern 12 is provided, 16 is a bar pattern for connecting the second basic transfer pattern 13 and the forward 180 degree turn corner pattern 12, and 17 is a transfer path 10a, 10d and a gate portion G.
Is a fourth basic transfer pattern for connecting to and, and 18 is a fifth basic transfer pattern connected between the fourth basic transfer patterns 17.

In each transfer path, a transfer pattern having a cycle longer than the cycle of the first basic transfer pattern 11 is used near the gate portion G and the turn-back corner portion. For example, the fifth
The period λ ′ of the basic transfer pattern 18 is formed so as to have a relationship of λ <λ ′ with the period λ of the first basic transfer pattern 11. Then, the magnetic bubbles transferred to the transfer path 10c in the direction of the arrow P are generated by the rotating magnetic field H _R applied in the pattern planes of the first basic transfer pattern 1
180 through the first, second basic transfer pattern 13, third basic transfer pattern 14, short bar pattern 15
Are sequentially transferred to the turn corner pattern 12, and the transfer direction P is further transferred by this order 180 degree turn corner pattern 12.
Is turned 180 degrees counterclockwise and transferred to the transfer path 10b. In this case, the above-mentioned short bar pattern 15
The bar pattern 16 has a function of preventing a significant decrease in the transfer margin when a magnetic bubble transfers from a transfer pattern having a large pattern volume to a transfer pattern having a small pattern volume.

However, in the forward 180-degree turn corner section configured as described above, the third basic transfer pattern 14 and the fifth basic transfer which are connected to the short bar pattern 15 for coupling the transfer path 10c and the transfer path 10d are connected. When the magnetic bubble B is transferred to the pattern 18, the short bar pattern 15 that faces the lower limit value side of the bias magnetic field H _B as shown in FIG.
It was discovered that an error occurred that the magnetic bubble B spreads at the tip of the. Similarly, between the transfer paths 10a and 10b, it has been found that an error occurs in which the magnetic bubble B transferred to the fourth basic transfer pattern 17 extends to the tip of the bar pattern 16. As a result, due to the occurrence of these errors, the total bias magnetic field margin of the magnetic bubble memory device is greatly limited, and as the rotating magnetic field H _R becomes larger, the error region E is expanded as shown in FIG. It was a big problem of impairing the characteristics of the device.

[Object of the Invention]

Therefore, the present invention has been made in view of the above-described conventional problems, and an object of the present invention is to eliminate a transfer error generated in a forward 180-degree turn corner portion and improve a transfer characteristic. Providing a memory device.

[Outline of Invention]

According to the present invention, the transfer pattern 1 is located on the transfer path adjacent to each tip so that the distance to each tip of the auxiliary bar pattern 15 inserted between the adjacent transfer paths 10b and 10c becomes large.
By shifting the vertices of 8'and 14 'in the direction away from each tip, bubble extension error is prevented and transfer margin is improved. According to the present invention, the following magnetic bubble memory device is provided.

A transfer pattern (11, 1) that transfers magnetic bubbles and has legs at the entrance and exit and a mountain-shaped back with vertices.
3, 17 ...) are arranged in a plurality, and the transfer direction is the first direction, the second direction opposite to the first direction, and the first (10d), second (10c) and third directions which are in the first direction. (10
a transfer path of b) and a turn corner pattern (12) for changing the transfer direction between the second and third transfer paths, assisting the transfer of magnetic bubbles, and one tip of the turn corner pattern and the second transfer path. A second transfer pattern (18 ') which is inserted between the first transfer pattern (14') in the transfer path and the other end of the second transfer pattern (18 ') which is close to the corner pattern in the first transfer path and is substantially back to back. A bent bar pattern (15) inserted between a third transfer pattern (17), which is close to the first transfer pattern and almost back to back, and comprises the first and second transfer patterns. Magnetic bubble memory device in which the positions of the vertices of the transfer pattern are set at positions (L ₁ and L ₂ ) farther from the center positions of the other tip and the one tip, respectively. Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 5 is a plan view of an enlarged pattern of an essential part of a forward 180 degree turn corner portion for explaining an embodiment of the magnetic bubble memory device according to the present invention. The same portions as those in FIG. 3 are designated by the same reference numerals. In the same figure, the third basic transfer pattern 14 'and the fifth basic transfer pattern 18' connected to the short bar pattern 15 have their vertex positions opposite to the magnetic bubble transfer direction P. It is formed by a transfer pattern that is deviated. The distance L ₁ from the tip of the short bar pattern 15 to the apex position of the third basic transfer pattern 14 ′ and the other tip of the short bar pattern 15 to the apex position of the fifth basic transfer pattern 18 ′. The distance L ₂ is larger than the distance in FIG. Similarly, the fourth basic transfer pattern 17 'connected to the bar pattern 16 constituting the forward 180-degree turn corner portion is also formed by a transfer pattern in which the vertex position is displaced in the direction opposite to the magnetic bubble transfer direction P. is formed to be larger than the length of the third view is also a distance L ₃ to the vertex of the basic transfer pattern 17 'from the end of the bar pattern 16. In this case, the third, fourth, and fifth basic transfer patterns 1
4 ', 17' and 18 'are transfer patterns 20 as shown in FIG.
The vertex C ₁ of the conventional is the distance l ₁ , l ₂ from the vertex C ₁ to the pattern end.
Uses a pattern eccentric in the direction opposite to the magnetic bubble transfer direction P for l ₁ = l ₃ .

With such a configuration, the distance L ₁ from each tip of the short bar pattern 15 to the apex of the third basic transfer pattern 14 ′ and the distance to the apex of the fifth basic transfer pattern 18 ′.
The distance L ₃ from L ₃ and the tip of the bar pattern 16 to the apex of the fourth basic transfer pattern 17 ′ becomes long, and as a result, the distance L ₃ gets away from the attraction magnetic poles generated at the tips of the bar patterns 15 and 16, Magnetic bubble has a bar pattern 1
There is no transfer error extending to the tips of 5, 16 and the bias magnetic field margin can be expanded.

In the above-described embodiment, the case where the apex of the transfer pattern is eccentric is described as a means for increasing the distance between the tip of the bar pattern and the apex of the transfer pattern connected to the bar pattern. Is not limited to this, and as shown in FIG. 7, the height h ₁ of the transfer pattern 21 in the direction orthogonal to the magnetic bubble transfer direction P is lower than the height h ₂ of the conventional pattern (h ₁ <H ₂ ) Since the distances L ₁ , L ₂ and L ₃ described above can be increased also by forming, it is needless to say that the same effect as described above can be obtained.

Further, in the above-described embodiment, the case where the Sieplon pattern is used as the transfer path pattern has been described, but the present invention is not limited to this, and FIG.
Of course, even if it is applied to a transfer path composed of a half-disk pattern, a C pattern, and a Kraft foot pattern shown in (b), (c), and (d), the same effect as described above can be obtained.

〔The invention's effect〕

As described above, according to the present invention, it is possible to eliminate the transfer error occurring in the forward 180-degree turn corner portion and expand the bias magnetic field margin, so that a magnetic bubble memory device having high quality and reliability can be obtained. That is, it has an extremely excellent effect.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration example of a minor loop, FIG. 2 is a diagram showing an example of its transfer pattern, and FIG. 3 is a plan view showing an enlarged pattern of an essential part showing an example of a conventional forward 180-degree turn corner portion.
FIG. 5 is a diagram showing transfer characteristics of a conventional forward 180 degree turn corner portion, and FIG. 5 is a plan view of an enlarged pattern of a main portion showing the forward 180 degree turn corner portion for explaining an example of a magnetic bubble memory device according to the present invention. 6 and 7 are enlarged plan views showing an example of the transfer pattern according to the present invention. 1 ... Simple loop type minor loop, 2, 3, 4 ... Folded type minor loop, 5 ... Asymmetrical chevron pattern, 6 ... Half disk pattern, 7 ... C pattern, 8 ... Club foot pattern, 10a, 10b, 10c, 10d ...
... Magnetic bubble transfer path, 11 ... first basic transfer pattern, 12 ... forward 180 degree turn corner pattern, 13 ...
Second basic transfer pattern, 14 '... Third basic transfer pattern, 15 ... Short bar pattern, 16 ... Bar pattern, 17' ... Fourth basic transfer pattern, 18 '
...... Fifth basic transfer pattern, 20 ... Basic transfer pattern.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Hironori Kondo, 3300 Hayano, Mobara-shi, Chiba, Hitachi, Ltd. Mobara factory (72) Inventor Tetsuaki Suzuki, 3300, Hayano, Mobara-shi, Chiba Hitachi, Ltd., Mobara factory, Ltd. (72) Inventor Hisaya Keida 3300, Hayano, Mobara-shi, Chiba, Hitachi, Ltd. in the Mobara Plant (72) Inventor, Seiichi Nishiyama 3300, Hayano, Mobara, Chiba, Ltd., in the Mobara Plant, Hitachi, Ltd. (72) Inventor, Mitsuru Sekino 1479 Kamimizuhonmachi, Kodaira-shi, Tokyo In-house (72) inventor, Hitachi My Kuro-Computer Engineering Co., Ltd. Medium ▲ Dai ▼ Hiro, 1479 Kamimizu-honmachi, Kodaira, Tokyo In-house (72) Inventor, Kadoyama Toshiya 1479 Kamimizuhonmachi, Kodaira-shi, Tokyo Hitachi Mai B-computer engineering shares meeting house

Claims (1)

[Claims] 1. A transfer direction in which a plurality of transfer patterns (11, 13, 17, ...) Transferring magnetic bubbles and having leg portions at an entrance and an exit and a mountain-shaped back portion having an apex are arranged. Are the first direction, the second direction opposite thereto and the first (10d), second (10c) and third (10b) transfer paths in the first direction, respectively, and the second and third directions. Turn corner pattern (12) for changing the transfer direction between the transfer paths of the first transfer pattern and the transfer pattern of the magnetic bubble, one end of which has the corner pattern and the first transfer pattern (14 ') in the second transfer path. Between the second transfer pattern (18 '), which is inserted between the first transfer path and the second transfer pattern (18') which is close to the corner pattern in a back-to-back relationship with the first transfer path. Third transfer pattern (1 ) And a bent bar pattern (15) inserted between the first and second transfer patterns, the positions of the vertices of the first and second transfer patterns are respectively defined from the other end and the one end. , A magnetic bubble memory device characterized by being set at positions (L ₁ , L ₂ ) farther from the respective center positions.