JPS5846791B2 - magnetic bubble device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for mounting a magnetic bubble crystal in a device that utilizes cylindrical magnetic domains (magnetic bubbles).

When a bubble crystal such as orthoferrite or garnet with uniaxial anisotropy is cut thinly or grown into a thin plate so that the axis of easy magnetization is perpendicular to the surface, and then excited in the direction of the axis of easy magnetization, it becomes cylindrical. Magnetic domains (hereinafter referred to as magnetic bubbles) are generated.

By applying a gradient magnetic field within the plane of the thin film, this magnetic bubble can be freely moved in the direction of the weaker applied magnetic field.

Then, the presence or absence of this magnetic bubble is determined using binary information IT
11, +101+, a logic element or a memory element can be configured.

In this way, if you select a plate-shaped crystal made of an appropriate material and apply a bias magnetic field of appropriate strength, magnetic bubbles will stably exist at any position, so you can use this property to generate magnetic bubbles. , by moving it to a certain location and detecting it, it can be used as memory.

Various methods are known for controlling magnetic bubbles, but
The most common method is control using a rotating magnetic field and permalloy pattern.

This involves applying a rotating magnetic field from the outside to, for example, T-shaped and T-shaped permalloy patterns formed on a bubble crystal.

When a clockwise rotating magnetic field is applied to attract the bubbles to the magnetic poles generated in permalloy using a rotating magnetic field, the bubbles move to the right, but the direction of the T-shaped, T-shaped pattern is 90°, 180°, and 2700 rotations. You can move the bubble downward, to the left, and upward, respectively.

For one rotation of the rotating magnetic field, the magnetic bubble is moved one period.

To generate this rotating magnetic field, a circular locus can be obtained on the bubble crystal plane by passing sine wave and cosine wave currents through the XY coils arranged orthogonally to each other.

The function of the drive coil is to provide a uniform horizontal magnetic field component to the bubble crystal plane, and since the drive coil is the only load on the drive circuit, an efficient design is desirable.

Generally, a solenoid or
A coil or a Helmholtz coil is used, but the conventional coil structure and mounting method are difficult to assemble.
There were many problems, including problems with maintainability, heat dissipation, and especially securing the window area for terminals.

FIG. 1 is an implementation diagram of a conventional solenoid coil.

In the figure, 1 is an X coil, 2 is a Y coil, and 10 is a bubble crystal mounting board.

First, the X coil 1 is wound on the bubble crystal mounting board 10, and the Y coil 2 is wound on top of it, perpendicular to the X coil, so the window area for terminals from the board 10 is very small, and the normal winding method is used. In this case, the area is limited to the area indicated by A.

Therefore, in order to further secure the necessary window area for terminal output, it is possible to increase the area of the bubble crystal mounting board 100 and expand the window area for terminal output to the area shown by B. As the area increases, it becomes necessary to expand the coil shape in order to keep the effective magnetic field plane constant.

For this reason, not only does the mounting efficiency deteriorate, but also the load on the drive circuit increases due to an increase in the inductance of the coil, or an extra wire or the like is required, which becomes uneconomical.

In addition, with the mounting method described above, the X-Y coils cannot be wound at the same time, assembly is troublesome, and the bubble crystal surface cannot be easily exposed, which is inconvenient in terms of maintenance. Due to its structure, the heat dissipation effect is also not good.

Further, the conventional coil structure and mounting method have many disadvantages as described above, such as severe restrictions on the mounting configuration brought about by the three-dimensional combination of the X and Y coils.

Therefore, in order to solve these drawbacks, the applicant has developed a second
The drive coil shown in the figure has already been proposed.

In the figure, 3 is an X coil, 4 is a Y coil, and 1 to ■ are rotating magnetic field regions.

In this way, both the X and Y coils are coils with a unique shape that spreads out on the plane, and by arranging them perpendicularly to each other, the X and Y coils overlap.
A rotating magnetic field is applied to the regions I, I[2m, and IV.

Basically, the X coil 3 and the Y coil 4 are arranged perpendicular to each other, but due to characteristics or structural requirements, the two coils may be arranged offset, for example, at an angle of 85° 75°.
It is also possible to arrange it at an angle of 45° or 45°.

In the case of mounting, a board is provided on which bubble crystals are placed at four locations where the X coil 3 and Y coil 4 are superimposed, I, n, III, and at positions corresponding to the TV area and having the same area as the area. , an iron plate is placed between the X coil 3 and the Y coil 4 or on one side.

FIG. 3 is a perspective view of the drive coil shown in FIG. 2.

As shown in the figure, this drive coil is constructed by winding a mouth-shaped or mouth-shaped insulated conductor wire of appropriate thickness multiple times in a horizontal plane, contrary to the concept of conventional solenoid coils. do.

Then, the flat coils are stacked vertically and assembled and mounted.

As a design standard, in order to form it as thin as possible, a single layer is often used, but a multilayer structure may also be used.

Of course, it is also possible to construct the above-described coil on a printed board or the like using printed wiring technology or the like.

Hereinafter, such a drive coil will be described as a planar coil.

FIG. 4 is an explanatory diagram of magnetic fields of a planar coil and a solenoid coil.

In the figure, A is a planar coil, and B is a solenoid coil.

When the planar coil shown in A in the figure is energized, the magnetic field vectors that are disturbed can be represented by H2, -Hx, and +Hx.

On the other hand, the solenoid coil is -H as shown in B in the figure.
The configuration is to utilize Hz rather than X, +HX, whereas the planar coil A in the figure uses -Hx, +
The two are fundamentally different in that they are configured to use HX.

FIG. 5 is a sectional view of a magnetic bubble device using the planar coil shown in FIG. 3.

In this device, two pairs of X and Y coils shown in FIG. 2 are prepared, and a bubble crystal mounting board is inserted and mounted between these coils.

In the figure, 5 is a coil plate, 6 is a bubble crystal, γ is a protection plate, 8 is a substrate using an alumina plate of 0.5 mm, and 9 is a spacer.

In this way, in the figure, the magnetic bubble function section (hereinafter referred to as a plane) composed of 6, 7, 8, and 9 is laminated from above and below with the coil plate 5.

FIG. 6 is a sectional view of a magnetic bubble device that is a further improvement of the embodiment shown in FIG.

In the figure, 3 is an X coil, 4 is a Y coil, 5 is a coil plate in which the X coil 3 and Y coil 4 are arranged and molded, 6 is a bubble crystal, and 11 is a conductor plate.

The basic method of a magnetic bubble device using a plane coil as a driving coil is as explained in Fig.
(omitted)), but the device shown in Fig. 6 only needs to have the coil plates 5 above or below the plane; A conductor plate 11 is provided on the side in place of the coil plate 5 described above.

This configuration has already been filed by the present applicant as Japanese Patent Application No. 48135524, so please refer to this for details.

With this configuration, although the efficiency is somewhat lower than when the coil plates 5 are provided on both sides of the plane, in practice, the conductor plate 11 exhibits the same effect as when the coil plates 5 are provided on both sides. .

Here, as the base plate 11, an aluminum plate is best from the viewpoint of strength and light weight, but other conductive plates such as steel or brass may of course be used.

Further, the coil plate 5 may have a laminated structure only on the upper and lower sides.

In this way, in fact, only one coil plate 5 is required, provided on one side of the plane, which is extremely economical, and the flat coil plate 5 and conductor plate 11
Since it uses only a laminated structure, the assembly process is very simple, mounting is easy, and the entire surface of the bubble crystal plane can be used as a terminal area, and the laminated board It is easy to maintain since it is simply removed, and it also has an extremely good heat dissipation effect because there is no need to encapsulate a chip with a crystal plane inside the coil as in conventional devices.

The present invention provides a magnetic bubble device as shown in FIG. 6 which has various advantages as described above, that is, a rotating magnetic field generating device consisting of a conductor plate provided opposite to a drive coil in which planar coils are arranged to intersect with each other. The present invention aims to further improve the magnetic bubble device equipped with the device and provide a magnetic bubble device with better characteristics and, therefore, more stable operation.

The object of the present invention is to provide a rotating magnetic field formed by a drive coil in which a plurality of planar coils are arranged so as to intersect with each other, and a conductor plate provided opposite to the drive coil for imparting a horizontal magnetic field component to the bubble crystal surface. In a magnetic bubble device equipped with a generator, this can be achieved by arranging the patterned surface of the bubble crystal to face the conductor plate.

The magnetic bubble device according to the present invention will be explained below with reference to FIG.

FIG. 7 is a diagram for explaining the present invention, in which the X coil,
This figure shows the intensity distribution of the perpendicular magnetic field component generated by a rotating magnetic field generator made up of a plane coil and a conductor plate, each having Y coils orthogonal to each other.

In the figure, 5 is a planar X coil as shown in Figure 2;
A coil plate 11 is a conductor plate in which Y coils are crossed and stacked.

The X coil and Y coil of the coil plate 5 constituting the rotating magnetic field generator
As described above, when sinusoidal currents with a phase shift of 90° are passed through each coil, a rotating magnetic field is generated in the direction of the conductor plate 110. In this case, the ideal rotating magnetic field is The present inventors have confirmed that it is located in a region close to the surface.

That is, as shown in FIG. 7, when looking at the distribution of the vertical component of the magnetic field generated by the coil plate (H7 in FIG. 4A, component magnetic field), it can be seen that it increases as the distance from the conductor plate 11 increases.

This vertical component magnetic field has a negative effect on the bubble crystal and the permalloy pattern formed on the bubble crystal, reduces the operating margin of the entire fruiting device, and makes the behavior of the bubble unstable, so it is not preferable. do not have.

Accordingly, the present invention is a magnetic bubble device of this type in which a bubble crystal is mounted so as to minimize the influence of the vertical component magnetic field on the bubble crystal, and its specific configuration is shown in FIG.

In the figure, 5 is a coil plate, 6 is a bubble crystal, 6' is a pattern-formed surface on which a permalloy pattern that controls functions such as generation, propagation, division, and detection of magnetic bubbles is formed on the bubble crystal, and 11 is a conductor plate. , 12 is an insulating film made of polyimide resin, and 13 is a solder bump.

As is clear from the figure, in the present invention, when the bubble crystal is placed on the conductor plate 11, the pattern forming surface 6 on the bubble crystal is
' is mounted facing the conductor plate 11.

In this way, the pattern forming surface C of the bubble crystal is placed on the conductor plate 11.
The permalloy patterns in the magnetic bubble itself and the various functional parts mentioned above that control the magnetic bubble by being mounted close to the magnetic bubble have less vertical component magnetic field, and therefore are controlled under a rotating magnetic field that is closer to the ideal. The bubble operates stably, and as a result, the reliability of the entire device is significantly improved.

In the present invention, since the bubble crystal 6 is mounted upside down on the conductor plate 11, the conductor pattern formed on the pattern forming surface 6' of the bubble crystal surface and the insulating film 12 of the conductor plate 11 are separated. For connection with the external lead-out pattern (not shown), the flip-chip connection method used in the semiconductor field can be used as is.

The embodiment shown in FIG. 8 shows an example in which the face down bonten puffer method is adopted.

The solder bumps 13 are formed by protruding a chromium-gold-solder layer from an external connection terminal portion of a pattern formed on a bubble crystal.

In the embodiment of the internal cause, a case using a face-down method is shown, but it goes without saying that the method is not limited to this method, and the same effect can be achieved even if, for example, a beam lead method is adopted.

In particular, these connection techniques have already been established in the semiconductor field and are effective as methods for efficiently attaching leads.

In addition, this kind of connection is extremely effective because there is no vertically rising part in the connection between the external lead pattern and the pattern on the surface of the baffle crystal, so there is almost no induced noise due to the rotating magnetic field in the pattern used as a sensing line, for example. be.

As explained above, according to the present invention, a magnetic bubble device with extremely stable operation can be realized.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of a conventional drive coil, Figs. 2 and 3 are explanatory diagrams of a planar coil used in the present invention, Fig. 4 is an explanatory diagram of the magnetic field of a planar coil and a conventional drive coil, and Fig. 5 is an explanatory diagram of a planar coil used in the present invention. ,
FIG. 6 is a sectional view of a magnetic bubble device using a planar coil. FIG. 7 is a vertical magnetic field distribution diagram for explaining the present invention in detail, and FIG. 8 is an embodiment of the magnetic bubble device according to the present invention. In the figure, 5 is a coil plate, 6 is a bubble crystal, 6' is a pattern forming surface, 11 is a conductor plate, 12 is an insulating film, and 13 is a solder bump.

Claims (1)

[Claims] 1 Equipped with a rotating magnetic field generating device consisting of a drive coil in which a plurality of planar coils are arranged to intersect with each other for imparting a horizontal magnetic field component to the bubble crystal plane, and a conductor plate provided opposite to the drive coil. In a magnetic bubble device, a pattern-formed surface of a bubble crystal is arranged to face the conductor plate, and a conductor pattern on the pattern-formation surface and an external extraction pattern formed on an insulating film of the conductor plate are arranged. A magnetic bubble device characterized in that the bubble crystal is connected and mounted on the conductor plate.