JPS61227286A - Magnetic bubble memory - Google Patents

Abstract

PURPOSE:To lower power consumption, to make compact a whole configuration and to make it thin by disposing a magnetic bubble memory element mounted on a flexible wiring substrate to the space section of a rotating magnetic circuit of a frame shape core, interposing the entire body in a case enclosing a rotating magnetic field made of an effectively conductive material and electrically connecting its peripheral part. CONSTITUTION:A core COR and respective coils COI constitute a magnetic circuit PFC giving a rotating magnetic field in plane to a chip CHI. A case RFS i a case for enclosing rotating magnetic field for accommodating the central square shape section of a substrate FPC, two chips CHI and an entire of the magnetic circuit PFC. Between the case RFS and the chip CHI, especially in a side surface section of the chip CHI, a space SIR is present and in this space section including the plane section of the chip CHI, a silicon resin is coated or packed, passivation effect is considered so as to prevent foreign matters from adhering to the main surface of the chip during assembling and the foreign mattrs from intrusion to the main surface of the chip or a side surface section.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a magnetic bubble memory, and particularly to a magnetic bubble memory suitable for reduction in thickness, size, and power consumption.

[Background of the invention]

Magnetic bubble memory devices, which have been put into practical use over the past few years, have magnetic bubble memory chips mounted on an E-shaped wiring board made of ceramic or synthetic resin.

It has a structure in which rotating magnetic field generating X coils and X coils, which are rectangular solenoid coils having an asymmetrical structure, are respectively inserted and arranged orthogonally. Since the X coil and the
Power consumption will increase, and 'xX coil
Since the coil requires a uniform inductor balance in order to provide a uniform and stable in-plane rotating magnetic field to the magnetic bubble memory element, the coil shape has to be an asymmetrical structure with different shapes and a larger structure. Ta. Furthermore, on the outer surfaces of these X coils and X coils, a pair of permanent magnet plates and their magnetic shunt plates that apply a perpendicular bias magnetic field to the magnetic bubble memory element are arranged, and their peripheral parts are covered with a resin mold. Because of this structure, the stacking thickness in the vertical direction increases, which is an obstacle to the demand for thinner and smaller magnetic bubble memory devices.

The closest prior art to the present invention known to the applicant is Patent Application Publication No. 55129 of 1974. This publication describes the structure of a frame-shaped core that surrounds a chip and a conductive magnetic field reflection box that completely surrounds them. However, no further specific structure is shown, and it is theoretically impossible to make an electrical connection to a chip completely surrounded by a conductor case from outside the conductor case without shorting it. Although it is possible, the description is clearly insufficient for people to think of putting it into practical use, including the fact that the method of attaching permanent magnets, magnetic shunt plates, bias coils, etc. is unknown. In other words, the embodiment of the present invention merely coincidentally coincides with the description in the above-mentioned publication in that a frame-shaped core is used as a result.

[Purpose of the invention]

An object of the present invention is to provide a magnetic bubble memory that can be made thinner.

Another object of the present invention is to provide a magnetic bubble memory that can be miniaturized by reducing the overall volume.

Another object of the present invention is to provide a magnetic bubble memory with reduced power consumption.

Another object of the present invention is to provide a magnetic bubble memory in which the VI product is reduced by reducing the inductance of the rotating magnetic field generating coil.

Another object of the present invention is to provide a magnetic bubble memory that allows or facilitates automation of assembly of component parts.

Another object of the present invention is to provide a magnetic bubble memory capable of increasing the number of connection terminals for input/output, etc., such as increasing capacity.

Another object of the present invention is to provide a magnetic bubble memory in which the inclination angle of the magnetic bubble memory element with respect to the direction of the bias magnetic field can be set easily and with high precision.

Another object of the present invention is to provide a magnetic bubble memory whose cassette can be made smaller.

Still another object of the present invention is to provide a magnetic bubble memory in which peripheral circuits of the magnetic bubble memory device can be manufactured at low cost.

[Summary of the invention]

According to one embodiment of the present invention, a drive magnetic circuit using a frame-shaped core is provided. The magnetic bubble memory chip is disposed on a flexible wiring board so as to be surrounded by and substantially flush with the frame-shaped core. The drive magnetic circuit and the magnetic bubble memory chip are housed in a rotating magnetic field confinement case made of a non-magnetic and highly conductive material. This configuration improves the uniformity of the rotating magnetic field and reduces the overall size.

It can be made thinner.

[Embodiments of the invention]

Next, the present invention will be explained in detail using the drawings.

(Overview of overall structure Figures 1 and 2) Figures 1 and 2 (a) and (b) are diagrams for explaining an embodiment of the magnetic bubble memory device according to the present invention. FIG. 2(a) is a partially broken perspective view, FIG. 2(a) is a bottom view thereof, and FIG. 2(b) is a sectional view taken along line 2B-2B of FIG. 2(a). In these figures, CHI is a magnetic bubble memory chip (hereinafter referred to as a chip). In these figures, the chip CHI is omitted and only one chip is shown, but in this example, two chips are arranged side by side. shall be.

(Chip yield is better with multiple chip configurations that match the total storage capacity than one large-capacity chip), F
The PC is equipped with two chips CHI and a chip C in the four corners.
COI is a flexible wiring board (hereinafter referred to as the board) that has a wire group extension for connecting the HI and external connection terminals.
is a drive coil (hereinafter referred to as a coil) that surrounds two chips CHI on almost the same plane and is arranged so that opposing sides are parallel to each other, and COR is a rectangular coil assembly CO.
It is a frame-shaped core (hereinafter referred to as the core) made of a fixedly arranged soft magnetic material that is provided so as to penetrate through the hollow part of I, and this core COR and each coil COI form a chip CH.
It consists of a magnetic circuit PFCt which applies an in-plane rotating magnetic field to I. The RFS is a rotating magnetic field confinement case (hereinafter referred to as the case) that houses the central rectangular portion of the substrate FPC, two chips CHI, and the entire magnetic circuit PFC.

Case RFS is formed by processing two independent plates,
The upper and lower plates are electrically connected on the side of the case.
A converging portion is formed in the peripheral portion so that the gap in the central portion is narrowed in a slightly wider range than the portion where the chip CHI is arranged. This constriction can also be used to position the magnet. Case PFS uses magnetic field confinement and soft substrate FP
It has the effect of killing two birds with one stone by mechanically supporting C.

In particular, there is a chip C between the case PFS and the chip CHI.
There is a gap SIR on the side surface of the HH, but this gap SIR, including the flat surface of the chip CHI, is coated or filled with silicone resin to prevent foreign matter from adhering to the main surface of the chip during assembly or water leaking after one assembly. A passivation effect is intended to reduce intrusion into the main surface or side surfaces of the chip. If complete airtight sealing is possible outside the case RFS, filling with resin SIH may be omitted. INM is a pair of inclined plates made of magnetic material placed outside the case RFS, and the second In the figure, the upper inclined plate INM becomes thicker as it approaches the left, and the lower inclined plate INM becomes thicker as it approaches the right, and both have an inclined surface formed on the case RFS side. As the material for the inclined plate INM, soft ferrite, permalloy, etc., which has a high magnetic permeability μ and a small coercive force He, may be used, and in this embodiment, soft ferrite was selected because it is easy to process the inclined surface. MAG is a pair of permanent magnet plates (hereinafter referred to as magnet plates) arranged inside a pair of inclined plates INM and overlapped therewith.ROM is a soft ferrite magnet arranged inside each magnet plate MAG and overlapped with it. These are a pair of magnetic shunt plates made of magnetic material. The magnet plate MAG is formed to have a uniform thickness over the entire surface. The INN is a pair of inclined plates made of a non-magnetic material with good thermal conductivity such as copper, which are placed on the inner facing surfaces of the pair of magnetic shunt plates HOM and overlapped therewith. These inclined plates INN are formed to have substantially the same inclination angle as the inclined plate INM, and have inclined surfaces in opposite directions. Inclined plate INM, magnet plate MAG, magnetic shunt plate HOM, and inclined plate INN.

When stacked and arranged and integrated to form a bias magnetic field generating magnet body BIM (hereinafter referred to as magnet body), the thickness of the entire laminated plate magnet body is formed to be uniform over almost the entire surface.

A pair of magnet bodies BIM are adhered to a central flat part surrounded by the constriction part of the case RFS.

BIC is a bias magnetic field generating coil (
The bias coil BIM (hereinafter referred to as bias coil) is used to adjust the magnetic force of the magnet plate MAG to match the characteristics of the chip CHI, or to test for the presence or absence of unnecessary bubble generation defects. erase)
It is driven when SHI includes a case RFS that houses the board FPC on which the chip CHI is mounted and the magnetic circuit PFC, and a pair of magnet bodies BIMa and BI on the outside.
The materials of the shield case SHI, which is an external magnetic shield case (hereinafter referred to as shield case) made of magnetic material that houses Mb and bias coil B and C, are as follows:
A magnetic material with a high magnetic permeability μ, a large saturation magnetic flux density Bs, and a small Hc is preferable, and permalloy and ferrite have such characteristics, but in this example, they are suitable for bending and are resistant to external mechanical forces. A strong permalloy iron-nickel alloy was selected. The PKG is a packaging case made of a material such as Al, which has high thermal conductivity and is easy to process, and is attached to the outer circumferential surface of the shield case SHI by adhesion or fitting. GNP are contact pads extending from the four corners of the substrate FPC and arranged to contact external connection terminals folded back on the back surface of the shield case SHI. TEF is a terminal fixing plate made of an insulating material that supports and fixes each contact pad GNP at a stepped portion of an opening. REG is sealed in the four inner corners of packaging case PKG, and the shield case RFS assembly is sealed in packaging case PKG.
It is a resin molding agent that is fixed inside.

(Features of the overall structure, FIGS. 1 and 2) The features of the overall structure of the magnetic bubble memory device shown in FIGS. 1 and 2 are enumerated as follows. However, the features of this embodiment are not limited to these, and other features will become clear from the explanations that follow from Figure 3, but here we will focus on the relationships between each component. The features are described below.

(1) Since the rotating magnetic field generating coil PFC is shaped like a picture frame and the bubble memory chip CHI is arranged within its section on almost the same plane, the thickness of the entire bubble device can be reduced. This is because in the current mainstream technology, the upper and lower surfaces of the chip are wrapped around the X and Y coils, so the thickness of the entire device is a function of the sum of the chip thickness, the X coil thickness, and the Y coil thickness.

(2) Since the x coil and the Y coil are arranged on almost the same plane, there are the following effects compared to the conventional structure in which the Y coil is wound on top of the X coil.

■The total winding length of the coil does not become long, so the inductance L can be reduced, making it possible to drive at low voltage and reduce power consumption.

(2) The distances between the X coil and Y coil and the chip CHI can be made equal, and the magnetic field distribution can be made balanced.

(3) Since the rotating magnetic field generating coil PFC is surrounded by the conductor case RFS, leakage of magnetic flux is reduced and drive efficiency for the chip CHI can be increased.

(4) Conductor case PFS is one rotation magnetic field Hr generating coil P
It prevents the alternating current magnetic field generated from the FC from leaking to the magnet body BIM with a large magnetic permeability μ, and on the other hand, substantially prevents the direct current magnetic field of the bias magnetic field Wb to be applied from the magnet body BIM to the chip CHI. There is an option not to.

(5) The conductor case PFS uses a material such as copper, which is harder than the epoxy glass used for conventional wiring boards.

Chip CHI can be strongly supported mechanically.

Therefore, when a multiple-chip mounting configuration is used to increase manufacturing yields, variations in the inclination angle between chips have a large effect on magnetic properties, but according to this embodiment, variations in the inclination angle between chips can be reduced. It can be held small.

(6) Flexible film board FPC as a wiring board
By using , the following effects can be obtained.

■The board thickness can be reduced.

■Since the lead bonding method can be used, the thickness occupied by the bonding part can be reduced compared to the conventional wire bonding method.

■The effects of ■ and ■ above are due to the magnetic circuit gap (magnetic permeability μ
A bias magnet MAG having a small thickness or a small planar area can be used, which leads to a thinner overall device or a smaller planar area.

■Wiring from the chip CHI can be bent freely. Therefore, the terminal portion can be turned over by 180°, and the planar area of the entire device can be limited.

■The width of the opening for wiring out of the rotating magnetic field confinement case RFS can be made smaller. Therefore, leakage of the magnetic field per rotation can be kept to a minimum.

(7) Since the external wiring of the wiring board FPC is concentrated at the corners of the rectangle, the opening of the rotating magnetic field confinement case RFS can be provided at the corner where the influence is least.

(8) Since the function of the inclined plate INN is not combined with the magnet or magnetization function, the following effects are obtained.

■To form the inclination angle, a material such as copper with good workability can be used.6 ■A material such as copper with good thermal conductivity can be used, and the heat generated by the rotating magnetic field generating coil COI can be efficiently dissipated.

■By using non-magnetic materials.

It is possible to prevent the magnetic field passing through the magnetic shunt plate ROM from being disturbed.

(9) It is preferable that the inclined plate INN be as thin as possible in order to reduce the magnetic gap.Compared to the magnet MAG and the magnetic shunt plate ROM, the inclined plate INN can be made thinner by limiting its width to the area necessary and sufficient for forming the inclined angle. This makes it easy to form an inclined angle in the thickness.

(10) Since a plate INM made of soft ferrite having a large magnetic permeability μ is inserted between the magnet MAG and the shield case SHI, the magnetic gap therebetween can be filled. Also.

The plate INM also contributes to heat radiation. Magnet M as plate INM
Since we have selected a material with a smaller holding force He than AG,
The effective thickness of the permanent magnet can remain uniform.

(11) The shield cases SH and I are made of a magnetic material such as permalloy with a large magnetic permeability μ.

Since the magnetic resistance of the magnetic circuit using the magnet MAG as a magnetic field source can be reduced, the thickness and planar area of the magnet MAG can be reduced.

(12) Since the shield case SHI is made of a magnetic material such as permalloy with a high saturation magnetic flux density Bs, it has the function of bypassing external magnetic field noise and preventing it from being transmitted to the chip CHH.

(13) The above (11) and (12) each lead to reducing the thickness of the shield case SHI.

(14) Since the shield case SHI uses an iron-nickel alloy such as permalloy, it is suitable for bending and protects the parts incorporated therein against external mechanical forces.

(15) Rotating magnetic field generating coil PFC and bias coil B
Since both ICs are core-type, the storage efficiency or packaging density within the packaging case SHI or PKG can be increased.

(16) Since the case RFS is inserted between the core COR and the magnetic shunt plate HOM, the interval can be finely adjusted by adjusting the thickness of the rotating magnetic field confinement case RFS and the bending angle in addition to the thickness of the coil COI. . The shorter this distance is, the smaller the overall planar size can be, leading to lower power consumption by reducing the coil length.

However, if the distance is too short, the DC bias magnetic field Hb from the magnet MAG will leak to the core 0OR having high magnetic permeability, and the uniformity of the bias magnetic field in the chip peripheral area will deteriorate. Therefore, this distance is very critical due to the above-mentioned characteristics, and according to the present structure, it can be precisely adjusted.

(17) Since the constriction portion is provided around the rotating magnetic field confinement case RFS, alignment of the magnet body BIM is easy.

(18) The inclined plate INN is made by arranging two plates made under the same manufacturing conditions so that there is a difference in rotation angle of 1806 degrees between the top and bottom surfaces of the chip, so that they are placed on the top and bottom surfaces with the chip in between. A pair of magnetic shunt plates ROM and a pair of magnets M
AG can be aligned almost parallel.

(Overview of assembly Fig. 3) Fig. 3 is an assembly perspective view for explaining the procedure for stacking and assembling each component constituting the above-mentioned magnetic bubble memory device, and the same reference numerals as above indicate the same members. . In the same figure, first, a board F has a connecting part for input/output wiring protruding from the 4th side and has an element mounting part in the center.
Board assembly BND with two CHI elements mounted on a PC
is placed inside the outer case RFSa, which has an insulating sheet glued at the position indicated by the dotted line on the bottom surface, and this board F
After installing the magnetic circuit PFC on the PC, fill it with silicone resin 5IR (not shown) and install the inner case R on top of it.
FSb is assembled into outer case RFSa, and side contact portions of outer case RFSa and inner case RFSb are electrically connected by soldering or the like. Next, after arranging the upper magnet body BIMa and the lower magnet body BIMb in the concave constriction portion provided on the outer surface of these outer case RFSa and inner case RFSb, this upper magnet body B I
A bias coil BIC wound in alignment is arranged in a gap (not shown) formed between the outer edge of M a and the inside of the inner case RFSb, and these are housed in the outer case 5HIa. Case S HI Sixth order inner case 5HI magnetically connects the side contact part of case S HI a and inner case 5Hub by welding etc.
The external connection terminal connection parts of the board FPC protruding from the four corners of the board FPC are folded back on the back surface of this inner case 5HIb as shown in FIG. Each external connection terminal covered with solder etc. is provided on each side.

A terminal fixing plate TEF with contact pads CoP (not shown) mounted in each opening is arranged in contact with each other, and each external connection terminal and contact pad COP are electrically connected by soldering or the like by thermocompression bonding or the like. The terminal fixing plate TEF and the packaging case PKG are then housed in a packaging case PKG and sealed with a hermetic seal or the like at the contact portion between the terminal fixing plate TEF and the packaging case PKG.

Next, the structure of each component mentioned above will be explained.

(Flexible wiring board Fig. 4) Fig. 4 is a diagram showing a board FPC, where A is a plan view thereof and B is a layout in which the connection parts of external connection terminals protruding from the four corners are folded back and combined. Plan view C is an enlarged cross-sectional view of 4C-4G of figure A, and the same figure is 4D- of figure A.
It is a 4D enlarged sectional view. In the same figure, the board FPC is
There is a square element protection part 1 in the center, small bent parts 2 (2a, 2b, 2c, 2d) at the four corners, and a square external connection terminal connection part (hereinafter referred to as connection part) at the tip. ) 3 (3a, 3b, 3c, 3d), and the overall shape is approximately windmill-shaped and is integrally formed. A rectangular opening 4 (4a, 4b) with a double frame structure to which the element C) (I is mounted and its terminal part connected) and a positioning 3
perforations 5 (5a, 5b, 5c) are provided, and one
A substrate protrusion 6 for positioning is provided at the tip of each connecting portion 3c.

In addition, as shown in FIG. C, this FPC board is made by forming a copper thin film on a base film 7 made of a polyimide resin film with a thickness of about 50 μm, for example, via an epoxy adhesive 8, and then applying the copper thin film to the desired shape. By etching into a pattern shape, wiring leads 9a as shown in FIG.
A circular external terminal 9b and an oval coil lead connection terminal 9c.

Patterns such as symbols 9d and index marks 9e are formed, and a transparent or semi-transparent cover film 10 is adhered to the upper surface of these through an adhesive 8 made of the same material as described above. And this board FP
In the opening 4 of C, an opening with highly accurate dimensions is formed in the base film 7 on the side where the element CHI (not shown) is mounted, and an opening with relatively large dimensions is formed in the cover film 10 on the upper surface side. Furthermore, base film 7
A wiring part 9a is exposed between the wiring lead 9a and the cover film 10, and a tin plating layer 11 is formed on the surface of the wiring lead 9a.
is formed, and the opening shape is formed to have a two-layer structure and a double frame structure. On the other hand, in the connecting portion 3, as shown in the figure, a circular opening 12 is formed at a portion of the cover film 10 corresponding to the circular external terminal 9b and the unillustrated elliptical external terminal 9c. A solder layer 13 is formed by plating or dipping on the copper thin film patterns of the external terminals 9b and 9c exposed from the external terminals 9b and 9c. Each of the external terminals 9b and 9c provided in these connection parts 3 is each connection part 3a.

3-b*3cy3d and bent part 2a
, 2b.

2c, 2d and each wiring lead 9a formed continuously on the element protection part 1. Each connection portion 3a is partially provided.

They are gathered in blocks 3b, 3c, and 3d, and their tips are exposed in the respective openings 4a and 4b.

That is, as shown in FIG. A, the wiring lead 9a of the connecting part 3a is located at the upper left of the opening 4a, the wiring lead 9a of the connecting part 3b is located at the lower left of the opening 4b, and the wiring lead 9a of the connecting part 3c is located at the lower left of the opening 4b. is wired to the upper right corner of the opening 4a, and the wiring lead 9a of the connecting portion 3d is wired to the lower right corner of the opening 4b. Then, this board FPC is connected to each connecting portion 3a in a later process.

3b, 3c, 3d are the respective bent portions 2a, 2b, 2C, 2
d and assembled as shown in Figure B,
The external terminals 9b and 9c on which the solder layer 13 is formed are exposed on the surface, and the surfaces of the wiring board 9a, symbol 9d and index mark 9e are covered with the cover film 10, so these patterns are It is configured so that it can be easily read through the cover film 10.

In such a configuration, the substrate FPC uses a polyimide resin film, and each bent portion 2 is provided at the four corners of the element protection portion 1.
Each connection 3a, 3b, 3 via a, 2b, 2c, 2d
c, 3d, and each of these connecting parts 3
By folding and combining a, 3b, 3c, and 3d to form the external terminal section, the element protection section 1 and the connection section are separated into two parts.
Since it has a layered wiring structure, the area of the element protection part 1 can be increased without reducing the area of the connection part 3, and at the same time, it is possible to increase the number of external terminals, and the overall shape can be made smaller. .

In addition, in such a configuration, the wiring leads 9a from each external terminal 9b to each opening 4a, 4b of the element protection part 1
Since the time can be significantly shortened, the influence of external noise etc. can be significantly reduced. That is, signals with a high S/N ratio can be input and output. Furthermore, a board protrusion 6 is provided at one end of the connecting part 3c, and an index mark 9e is provided on this protrusion 6, so that when the board is folded back and assembled, it can be used for displaying the central part of the board.
I (see Figure 2) can be used for positioning when assembling, distinguishing the type of wiring lead 9a, or displaying the product model. It can be streamlined. Additionally, holes 5a, 5b, 5c are provided at both ends of the element protection portion 1 of the FPC board.
By providing a
The positioning of the HI becomes easy, and the ease of assembly can also be streamlined.

(Substrate Assembly Figures 5..6.7) Figure 5 is a plan view showing the element CHI mounted on the aforementioned substrate FPC. In the same figure.

Two elements CHI are mounted in the element mounting part 1 of the board FPC in parallel arrangement between the openings 4a and 4b, and the board assembly BN is assembled.
As shown in the enlarged plan view in Fig. 6, one of the elements CH is constructed by integrating two blocks of the IMb chip, and two elements CHI have four blocks in total. It constitutes a 4Mb chip. In one block of the element CHI shown in FIG. 6, thick lines indicate conductor patterns and thin lines indicate chevron pattern transfer paths, respectively. In addition, the element CHI shown in FIG.
A gold bump 15 is interposed between each bonding pad 14 provided by gold plating on the end of the HI and the wiring lead 9a on which the tin plating layer 11 of the substrate FPC opening 4 is formed, and thermocompression bonding is performed. It is mounted by lead bonding using Au-Sn eutectic.

According to such a configuration, the openings 4a, 4 of the substrate FPC
The wiring lead 9a of b and the bonding pad 14 of the element CHI are connected by lead bonding using Au-3n eutectic, and the element CHI can be supported and fixed, so the connection strength can be greatly improved and the thickness can be reduced. becomes. In addition, the surface of the element CHI is the element mounting part 1 of the substrate FPC.
Since the surface of the element CHI is covered with
Handling properties can be improved, and the mechanical strength of the FPC board can be maintained. Also,
According to such a configuration, each element CHI is composed of two blocks, and two elements CHI are composed of four blocks, so that each block is connected to the nearest connecting portion 3.
a, 3b, 3c.

Wiring can be distributed over 3d, and the symmetry of the element C) (I arrangement can be obtained, making testing, inspection, etc. extremely easy.

Furthermore, four connection parts 3a, 3b, 3c, 3 are attached to the board FPC.
d, the wires for the magnetic bubble detector DET and pine pull of each element CHI are distinguished from other functional wires and gathered at one connection point, and this connection point is selected to be away from the noise source. By placing
It is possible to exchange input/output signals with extremely low noise.

(Drive Magnetic Circuit FIGS. 8 and 9) FIG. 8 is a diagram showing the magnetic circuit PFC, and FIG. 8A is a perspective view, and FIG. 8B is a plan view showing the drive magnetic circuit. In the figure, the magnetic circuit PFC is.

A coil COI consisting of four sets of coils 20a, 20b, 20c, and 20d is formed by winding wires in the direction of the arrows on mutually parallel opposing sides of a frame-shaped core COR made of a soft magnetic material.
are wound, and the coils 20a and 20 on opposite sides
B is wound in series through the connection point 21b to form the X coil 2.
2a is wound in series with coils 20c and 20d via a connection point 21a to form a Y coil 22b.

Then, currents 1x and Iy (for example, triangular non-current) whose phases are different by 90 degrees are applied to the X coil 22a and the Y coil 22b.
By supplying , a leakage magnetic field Hz is generated in the X-axis direction and a leakage magnetic field H) is generated in the y-axis direction, as shown in FIG. .

In addition, the magnetic circuit PFC configured in this manner has windings arranged around a rectangular parallelepiped magnetic core 23 made of one soft magnetic material with taps 24 for each block, as shown in a perspective view in FIG.
, and wind them in series to form a pair of .

A pair of coils, for example coils 20a and 20b
After forming the coils 22a, each coil 20a and 2. O
A wide groove 25 having a certain width and a narrower groove 26 are formed by cutting between the two grooves 26 and 26, and then cut from the narrow groove 26 to create a width divided into the two. The wide grooves 25 are combined and glued together in directions orthogonal to each other to form a picture frame shape as shown in FIG. Alternatively, the pair of X coils 22a may be formed by winding the coils 20a and 20b through the taps 24 around the rectangular parallelepiped core 23 in which the wide groove 25 and the narrow groove 26 described above are formed in advance. . Furthermore, the pair of Y coils 22b described above are formed in exactly the same manner.

In such a configuration, the coils 20a and 20b are wound in series around the rectangular parallelepiped magnetic core 23 with taps 24 provided, so when assembled as shown in FIG. 8, the wires are connected by crossing each other ( connection points), and the winding routing can be simplified.

According to such a configuration, the X coil 22a and the Y coil 2
2b has a symmetrical structure, resulting in a rough coupling,
The inductance balance is improved, and magnetic interference between magnetic bodies due to leakage magnetic fields can be prevented. Furthermore, since the magnetic circuit PFC has a frame-shaped structure that is not disposed on the upper or lower surface of the element CHI, the thickness in the stacking direction is reduced, making it possible to reduce the thickness.

(Rotating magnetic field confinement case Fig. 10.11.12) 1st
Figure 0 is a diagram showing the case RFS, and Figure A is a plan view.
Figure B is a sectional view taken along the line 10B-10B. In the figure, the inner case RFSb has a frame-shaped constriction part 30 whose central part is concave, and whose opposing end sides extend upward by approximately 90 degrees.
The case RFSb has a bent portion 31 bent at 0 degrees and cutout portions 32 cut diagonally at each of its four corners, and the case RFSb is made of a highly conductive material,
For example, it is formed by pressing an oxygen-free copper plate. In this case, the constricted portion 30 and the bent portion 31 can improve the mechanical strength of the inner case RFSb in the torsion direction, and can appropriately limit the outer diameter dimensions in the longitudinal and lateral directions between the bent portions 31 facing each other. . Further, the aperture section 30 can appropriately adjust the distance between the magnet body BIMb arranged on the outer surface side of this case RFSb and the element CHI arranged on the inner surface side. Note that the cutout portions 32 provided at the four corners are each bent portion 2a of the board FPC disposed within this case RFSb.

It forms the drawer parts 2b, 2c, and 2d.

According to such a configuration, the inner case RFSb can be formed by a press working method, and therefore can be manufactured with high precision dimensions and at low cost.

Note that, although oxygen-free copper is used for the inner case RFSb, a plate material made of copper, silver, gold plate, or an alloy plate thereof may be used.

FIG. 11 is a diagram showing an outer case RFSa corresponding to the inner case RFSb described above, in which FIG. 11A is a plan view and FIG. 11B is a sectional view taken along the line IIB-11B. In the same figure,
This outer case RFSa is similar to the inner case RFS described above.
It is formed using the same material and manufacturing method as b, and its structure is almost the same as described above, with a frame-shaped constriction part 33 whose central part is concave, and the opposite end thereof is bent upward at approximately 90 degrees. It is configured to have a bent portion 34 and a notch portion 35 cut diagonally at each of its four corners.
In this case, the mutually opposing bent portions 34 are formed so that the inner dimensions thereof are approximately the same as the outer dimensions between the bent portions 31 of the inner case RFSb described above, and the height H is increased. has been done. Note that this aperture part 3
3 and the notch 35 are the inner case RFSb described above.
It is formed to have approximately the same dimensions as.

The outer case RFSa and the inner case RFSb configured in this way are constructed by inserting the inner case RFSb into the outer case RFSa as shown in the plan view in FIG. 12A and in the 12B-12B sectional view in FIG. , and the outer surface of the bent portion 31 of the outer case RFSa are brought into contact with each other and connected, thereby integrating the case RFS and assembling the case RFS.

(Case assembly Figure 13) Figure 13 shows the board assembly BND inside the case RFS mentioned above.
This figure shows a cross-sectional view of the storage arrangement. In the figure, a polyimide film 36 having a thickness of about 001Mn, for example, is adhesively arranged as an electrically insulating sheet on the bottom surface of the outer case RFSa, and a board assembly BND is mounted on this film 36.

In addition, magnetic circuit FPCs are arranged on the peripheral edges thereof, and after applying an epoxy adhesive 37 to the upper surface of the board assembly BND, the inner case R
FSb is inserted and bonded. In this case, the inner surface of the bent portion 34 of the outer case RFSa and the outer surface of the bent portion 31 of the inner case RFSb are electrically connected by metal flow or soldering at the portion indicated by the X mark.
Mechanically joined. Also, this outer case RFS
A gap between a and the inner case RFSb is filled with silicone resin SIR, and a board assembly BND and a magnetic circuit PFC are fixedly arranged. In this case, these outer case RFSa and inner case RFSb are
The bent portions 2 (2a, 2b, 2c, 2d
) is being pulled out. 38 is a lead wire for connecting the coil COIs or connecting the coil COI to the external terminal 9c provided on the FPC board.

In such a configuration, when a leakage magnetic field is generated by driving the magnetic circuit FPC, an induced current flows through the case RFS to form a closed loop, and this induced current confines the rotating magnetic field within the case RFS, so that the element CHI is applied with a uniform rotating magnetic field.

According to such a configuration, the board F is placed in the concave portion at the center between the outer case RFSa and the inner case RFSb.
The element CHI installed in the PC.

Since the magnetic circuits PFC are sandwiched and disposed within the convex portions of the peripheral portion, the packaging effect can be improved and the ease of assembly can be greatly improved.

Further, by reducing the volume covered by the outer case RFSa and the inner case RFsb, the VI product (CC volume) can be reduced, and the magnetic circuit FPC that generates the rotating magnetic field can be downsized. Furthermore, by providing concave portions formed by the constricted portions 30 and 33 in the outer case RFSa and the inner case RFSb and reducing the gap between the opposing concave portions, the rotating magnetic field can be generated by the component perpendicular to the plane of the element CHI (
Z component) is close to zero and there is only a horizontal component, and uniformity can be improved.

(Magnet Figure 14) Figure 14 is a diagram showing the magnet body BIM, in which Figure A is a plan view, Figure B is a side view, and Figure C is a front view.

In the same figure, the m-cuboid BIM has an inclined plate 1 made of a non-magnetic material, such as copper, with one of the opposing surfaces having a predetermined inclined surface.
'N N, a first magnetic shunt plate ROM having a uniform thickness placed on the slope side of this inclined drawing NN, and a plate thickness of the first magnetic shuffling plate HOM placed on the top surface side of this first magnetic shuffling plate HOM. Uniform magnetic plate MAG
and a second magnetic shunt plate HOM having an inclined surface on the upper surface side of the magnet plate MAG are sequentially laminated and integrated with an epoxy adhesive, so that the entire laminated plate thickness covers almost the entire surface. It is configured to be uniform. and,
A uniform magnetic field for generating a bias magnetic field is emitted from the upper and lower surfaces of the magnet plate BIM over almost the entire surface.

(Bias Coil FIG. 15) FIG. 15 is a diagram showing the bias coil BIC, where A is a perspective view and FIG. B is a cross-sectional view taken along line 15B-15B. In the same figure, the bias coil BIC has a winding 40 whose outer surface is coated with an insulating member such as a thermosetting resin, and is wound in an array with a cross section of 5 x 4 wires so that the overall shape has a picture frame shape. After that, it is crimped by heat welding, cooled, and formed into a frame shape of a predetermined value. In this case, the thermosetting resin coated on the outer surface of each winding 40 is thermally welded to each other, and each winding 40 is clogged and formed by pressure bonding, and by cooling, each winding 40 is hardened in a bundled state. Therefore, it is formed into a predetermined picture frame shape.

(Mounting the magnet and bias coil on the case assembly
Figure 16) Figure 16 shows the magnet body BIM and bias coil BIC described above inside the case RFS assembly explained in Figure 13.
This figure shows a cross-sectional view incorporating the. In the same figure, an upper magnet body B I M a and a lower magnet body BIMb are adhesively arranged on the upper and lower surfaces of the case RFS assembly that houses the board assembly BND and the magnetic circuit PFC inside, and furthermore, this upper magnet body B A bias coil BIC is housed in a frame-shaped groove formed by being surrounded by the peripheral edge of IMa and the bent portion 31 of the inner case RFsb. In this case, the upper magnet body BIMa and the lower magnet body BIMb are made of the same material and two dimensions, and the inclined plate INN side of these magnet bodies BIMa and BIMb is connected to the constriction part of the inner case RFSb. 30 and a concave portion surrounded by the constriction portion 33 of the outer case RFSa, in close contact with each other.

In such a configuration, a pair of magnet bodies BIMa,
Since the BIMb is placed and the bias coil BIC can be placed in the frame-shaped groove formed on the periphery of the BIMb,
The overall thickness of each component in the stacking direction is reduced, making it possible to make it smaller and thinner. Further, since a frame-shaped space groove is formed between the outer case RFSa and the outer edge portion of the lower magnet body BIMb, the bias coil BIC may be placed in this portion, or a new bias coil may be provided. Furthermore, it is also possible to form a bias coil by winding the wire as a coil bobbin.

(Magnetic shield case Fig. 17, 18, 19) Fig. 17
The figures show the shield case SHI, with figure A being a plan view and figure B being a 17B-17B cross-sectional view thereof. In the same figure, the outer shield case S HI a has a flat portion 51 and an end side opposite to the flat portion 51 that extends upward by approximately 90 mm.
The folded part 52 that is folded back at the same time, and the folded part 52
The shield case 5HIa has a recess 53 partially cut out in the center thereof, and a notch 454 cut diagonally at each of its four corners.This shield case 5HIa has high magnetic permeability and high It is formed by pressing a material having a saturation magnetic flux density and preferably a high thermal conductivity, such as a permalloy plate.

18A and 18B are diagrams showing an inner shield case 5HIb corresponding to the above-mentioned outer shield case 5HIa, with FIG. 18A being a plan view and FIG. 18B being a cross-sectional view taken along line 18B-18B. In the same figure, this inner shield case 5HIb is formed using the same materials and manufacturing method as the above-mentioned outer shield case 5HIa, and its structure is almost the same as above, with a flat part 55 and an opposite end of this flat part 55. A bent portion 56 that is folded upward at approximately 90 degrees, a recessed portion 57 that is partially cut out in the center of this bent portion 56, and notched portions 58 that are cut diagonally at each of its four corners. It is configured with In this case, the mutually opposing bent portions 56 have an outer dimension approximately equal to the inner dimension between the bent portions 52 of the outer shield case 5HIa described above, and have a reduced height H. It is formed.

The outer shield case 5HIa and the inner shield case 5HIb configured in this way are arranged inside the outer shield case SHIa as shown in FIG. 19A as a plan view and as shown in FIG. Insert shield case 5HIb and remove outer shield case S.
Spot welding or solder welding is applied to the recess 59 formed by the recess 53 of the HI a and the recess 57 of the inner shield case 5 HIb, and the outer shield case S HI a is assembled by magnetically and mechanically fixing the recess 59 . It will be done. In such a configuration, the bent portion 52 of the outer shield case S HI a and the bent portion 56 of the inner shield case 5 HIb should not be set in the lateral direction, that is, in a direction that intersects with the laminated direction, but aligned in the laminated direction. As a result, the lateral dimension can be reduced, making it possible to achieve compactness and high integration of component parts.

(Magnetic shield case assembly FIG. 20) FIG. 20 shows the case RFS assembly, which incorporates the board assembly BND and magnetic circuit FPC inside the shield case SHI assembly described in FIG. magnetic plate BIM
Fig. 3a shows a cross-sectional view incorporating an assembly consisting of BIMb and bias coil BIC. In the same figure, inside the outer shield case 5HIa, there is an upper magnet body BIM a in the center from the bottom side, a bias coil BIC in the peripheral part, and a case RFS assembly (board assembly BND and magnetic circuit FPC inside). etc.)
, After sequentially stacking and arranging the lower magnet bodies BIMk, the inner shield case 5HIb is inserted, and the recess 53 of the outer shield case SHIa and the inner shield case 5 described above are inserted.
It is fixed and sealed by welding in a recess 59 (see FIG. 19) formed with the recess 57 of HIb. In this case, by filling the shield case SHI with grease or the like, the internal components will come into close contact with each other, and the heat generated from the case RFS will be transferred to the outside through the shield case SHI. can be released to Also,
The heat dissipation effect can be improved by making the case RFS and the shield case SHI contact each other at their sides by press-fitting.

In such a configuration, the outer shield case 5HIa
Place the case RFS assembly on the bottom side of the
．． By arranging the outer shield case SHI a and the inner shield case 5 so that they face each other,
Since each component layered between the HIb and the HIb can be arranged in close contact with each other, it is possible to make the device smaller and thinner, and at the same time, a heat dissipation effect can be obtained.

(Packaging case FIG. 21) FIG. 21 is a diagram showing a packaging case PKG, in which FIG. 21A is a plan view and FIG. 21B is a sectional view taken along line 21B'-21B. In the same figure, packaging case PKG
is formed by drawing a material with good thermal conductivity, for example, an aluminum plate with a thickness of 0.5 nm, and although not shown in the figure, it can be used by improving the shape of Ia on its outer surface. .

In such a configuration, this packaging case P
The KG serves as the outer case after the magnetic bubble memory device is completed and also functions as a heat sink, and its inner corner also functions as a mold during resin molding using the botting method described below. .

(Terminal fixing plate and contact pad Fig. 22.23)
FIG. 22 is a diagram showing a TEF with fixed terminals.

Figure A is a plan view, Figure B is a 22B-22B sectional view,
Figure C is its rear view. In the same figure.

The terminal fixing plate TEF is a material that has electrical insulation properties.

For example, it is made of a glass epoxy resin plate 60.

Its outer shape is formed to have dimensions in the vertical and horizontal directions such that it can be inserted into and removed from the opening of the packaging case PKG, and a large number of resin plates are formed on the resin plate 6o except for the peripheral area. Through holes 61 are formed in a matrix arrangement at predetermined intervals in the vertical and horizontal directions, and non-through holes 62 having concave cross sections that are not rotationally symmetric are provided at the corners of these through holes. A mark 63 made of a white coating film or the like is attached to the inside of the non-penetrating hole 62, for example, for locating directionality or features. In addition, this resin plate 60
As shown in Figure B, a large number of through holes 61 are provided with large diameter openings 64 coaxially communicating with each other on the back side of the through holes 61, and all of these openings 64 are connected to the plate. It has a depth of about 60% of the thickness and communicates with the through hole 61 with a step in the middle. Further, as shown in FIG. C, the back side of the resin plate 60 has a depth approximately equal to the depth of the opening 64 along its peripheral portion, and has a different width in the plane direction and a concave cross section. A groove 65 is formed, and the inside of this groove 65 constitutes a passage portion and a connection portion for the winding of the coil COI and the winding of the bias coil BIC.

Furthermore, the corner portions 66 of this resin plate 60 do not have a concave shape;
It has a predetermined plate thickness and is attached to the inner surface of the packaging case PKG described above to provide a contact surface. In this way, the back side of the resin plate 60 is formed to have a two-tiered structure with different plate thicknesses.

FIG. 23 is a diagram showing the contact pad GNP, with FIG. 23A being a plan view and FIG. 23B being a sectional view thereof. In the figure, contact pad GNP is.

Nickel plating layer 71. It is constructed by forming a gold plating layer 72.

(Final assembly FIG. 20.4.2) For each component configured in this way, first, the shield case assembly described in FIG. 20 is inserted into the packaging case PKG described above. In this state, each connection portion 3a, 3b, 3ct 3d (fourth
(see Figure A) are bent at approximately 90 degrees from each bent portion 2a, 2b, 2c, and 2d and protrude. Next, resin molding is performed at the four corners of the packaging cases P and KG by a botting method to create this package. case PKG
Each unique part is fixedly arranged inside. Subsequently, each of these connections 3 a , 3 b , ° 3 c , 3 d
are further bent at approximately 90 degrees at the corresponding bent portions 2a, 2b, 2c, and 2d and assembled to the outer surface of the inner shield case 5HIb via adhesive as shown in FIG. 4B, and then the terminal fixing plate is assembled. The contact pads CN and P are mounted in each opening 64 on the back side of the TEF, or the side surface of the contact pad GNP is further fixed with adhesive and inserted into the packaging case PKG, and each connection part 3a, 3 is inserted into the packaging case PKG.
b, 3c.

Place it in contact with 3d. In this case, each connection part 3a.

Since the arrangement pitch of each external terminal 9b provided in 3 b + 3 c g 3 d matches the arrangement pitch of each contact pad GNP, each external terminal 9 b and contact pad GNP are in electrical contact. do.

Next, from the back side of the terminal fixing plate TEF placed, each through hole 61
For example, by inserting a heating element with a thin tip into the contact pad GNP and thermocompressing the contact pad GNP, each external terminal 9b and the corresponding contact pad GNP are electrically connected, and the terminal fixing plate TEF is also mechanically connected at the same time. After fixing, the magnetic bubble memory device shown in FIG. 2 is completed.

(Magnetic bubble memory element No. 24, 25, 26,
27, 28) FIG. 24 shows a sectional view of the vicinity of the bonding pad PAD of the above-mentioned magnetic bubble memory element CH. In the same figure, GGG is gadoli
The substrate is a nium-gallium-garnet substrate, and the LPE is a bubble magnetic film formed by a liquid phase epitaxial growth method, and an example of its composition is as shown in Table 1 below.

Table 1 1ON shows the ion implantation layer formed on the surface of the LPE film to suppress hard bubbles. SPI is the first spacer, for example 3000 thick SIO, formed by gas phase chemical reaction.

CND1 and CND2 indicate two conductor layers, which have the function of controlling bubble generation, copying (splitting) and exchange, which will be described later, and the lower first conductor layer CND1 is
, and the upper second conductor layers CND2 are each formed of a material such as AU. SF3 and SF3 are interlayer insulating films (second and third spacers) made of polyimide resin, etc., which electrically insulate the conductor layer CHD and the transfer pattern layer P, such as permalloy, formed thereon. This is a passivation film made of SioJI or the like formed by a gas phase chemical reaction method. PAD indicates a bonding pad of the element CHI, and a thin connector wire such as an Afl wire is bonded here by thermocompression bonding or ultrasonic bonding. This bonding pad PAD is the lower first layer PA
D, is Cr, second layer PAD in the center, Au layer, upper third layer
The layers PAD3 are each made of a material such as an Au plating layer, and the second layer PAD and the third layer PAD are made of Cr,
P indicates a layer used for a bubble transfer path, a bubble division 1 generation, replacement and detection section, and a guardrail section, and may be formed of a material such as Cu. express.

In the example of FIG. 24, this transfer pattern layer P is transferred to the lower layer P1.
Although e-Ni is used for the upper layer P2 and Fa-Ni is used for the upper layer P2, it is also possible to interchange the two materials vertically as described above.

Hereinafter, the transfer pattern layer consisting of the plurality of layers described above will be transferred to the element C.
) (An example of application to each part of I will be explained using the plan views from Fig. 25 onward. In these plan views, each layer of the transfer pattern layer is formed by self-line, so it is represented by the same outline line. It should be noted that Figure 25 shows the bubble detector part, and MEM is the main magnetoresistive element, which shows that the resistance value changes when a bubble stretched horizontally in a band shape passes through it. MED is a dummy magnetoresistive element with a pattern similar to the main magnetoresistive element MEM, and is used to detect noise components due to the influence of a single rotation magnetic field.Main magnetoresistive element Although only two stages are shown above the MEM, there are several dozen stages of bubble stretchers ST that stretch the bubbles laterally and transfer them downward. Note that PR indicates the bubble transfer direction. ing.

ER is a bubble eraser, and when a bubble reaches the conductor layer CND, it is erased. A guardrail GR consisting of three rows of pattern groups is provided around this detector and between the dummy and main detection.
It is designed to expel unnecessary bubbles generated inside the guardrail GR to the outside thereof, and prevent unnecessary bubbles generated outside the guardrail GR from entering inside it. In addition,
In the plane pattern diagrams shown in FIG. 25 and subsequent figures, patterns other than the conductor layer CND indicate the transfer pattern layer P explained in FIG. 24. In the figure, the signal-to-noise ratio (S/
N ratio) was improved. For example, when a three-layer permalloy layer with a SiO film interposed between each layer is used as a transfer pattern, the S/N ratio is more than twice that of a single-layer permalloy layer, as shown in Table 2 below. can be improved.

Table 2 Furthermore, the performance of the guardrail GR is also improved by reducing the holding force He, such as increasing the rate of eliminating unnecessary bubbles.

FIG. 26 shows the magnetic bubble generator GEN, and by making the transfer pattern layer P multilayer, the current generated by the magnetic bubble can be reduced, and the life of the conductor layer CND of the magnetic bubble generator can be extended. It became possible. Therefore, a semiconductor element with a small current capacity value can be used for the drive circuit of the conductor layer CND, and the cost can be reduced.

FIG. 27 shows a write major line WML formed by a transfer pattern sequence such as a minor loop m, Pw, ~Pw, etc. formed by a transfer pattern such as P a = P h, and a swap gate formed by a hairpin-shaped conductor layer CND. It shows the part. In the same figure, P is the same as the transfer pattern P7 in the bubble generator GEN of FIG. Transferred to WML. When a current is passed through the swap conductor layer CND, the transfer pattern Pd of the minor loop m is
The magnetic bubbles are transferred to the transfer pattern Pw of the major line WML through transfer patterns PA and Pm, and the magnetic bubbles from the major line PW are transferred to the transfer pattern P of the minor loop via transfer patterns Pk, Pj, and Pi.
The data is transferred to e and the bubbles are exchanged, that is, the information is rewritten. Note that the rightmost minor loop md is not provided with a swap gate, but this is a dummy loop in which no magnetic bubble is injected to reduce the peripheral effect. In this way, the transfer pattern layer P at the exchange position
By multilayering i''Pm, magnetic bubbles can be exchanged with a small current value.

Further, as shown in FIG. 28, a magnetic bubble copying machine, that is, a divider, can be driven with a small current value as well. In the figure, a magnetic bubble is normally transferred along a path from Pn to Pg, Ps''Px, and when a current is passed through the conductor layer CHD, the bubble is divided at the position of the transfer pattern Pg, and one divided magnetic bubble is transferred. The bubble is transferred to the read major line RML via P)'+Ps~P1°.

(Holding magnetic field and rotating magnetic field FIG. 29) Magnet plate MAG is arranged at an angle of about 2 degrees with respect to element CHI. This is so that the bias magnetic field Hb is applied to the element CHI with a slight deviation from the perpendicular direction, thereby creating a holding magnetic field Hdc that improves the start and stop margins of bubble transfer by about 6 (Oe) (No. 29 Figure A).

As shown in FIG. 29A, due to the inclination of the angle θ between the magnet body BIM and the element CHI, the DC magnetic field Hz is as follows.

It has a component Hdc in the X7 plane. The magnitude of this in-plane component Hdc is Hdc-sinθ, and usually Hdc-sinθ=5 (Oe) to 6 (Os)
The inclination angle θ is selected so that Further, the direction of this in-plane component Hdc is inclined so as to coincide with the start/stop (St/Sp) direction (x-axis direction) of the rotating magnetic field Hr.

This xy-plane component Hdc is a known magnetic field called a holding field, which functions effectively for the start/stop (St/Sp) operation of the rotating magnetic field Hr. Note that the magnitude of the bias magnetic field Hb acting perpendicularly to the element CHI surface is H2-cos θ.

Now, since the above-mentioned holding field HdC always acts on the xy plane of the element CHI, the rotating magnetic field Hr' acting on the element CHI is eccentric, as illustrated in FIG. 29B. In the figure, Hr is a rotating magnetic field applied from the outside, and Hr' is a rotating magnetic field acting on the element CHI.

In this case, the rotating magnetic field Hr' acting on CHI is a combination of the rotating magnetic field Hr applied from the outside and the in-plane component Hdc, and the center 0' of the rotating magnetic field Hr' is the start/stop (S t/S p ) direction, which is the +X-axis direction, by an in-plane component Hdc. Therefore, as is clear from the results in the figure, even if the strength of the externally applied rotating magnetic field Hr is 1 Hrl, the strength IHr'l of the rotating magnetic field that effectively acts on the blocking CHI is the same as that of the rotating magnetic field Hr. Depends on the phase. That is, IHr in the St/SP direction
'l becomes IHrl+IHd cj, and I Hr l
Strength of holding field Hdc compared to IHd
Only cl is getting stronger. Conversely, lHr'l in the opposite direction to the St/SP direction is l Hr l-I Hd c
I, which is weaker by 1Hdcl compared to 1Hrl.

(Peripheral Circuit FIG. 30) Finally, the peripheral circuit of element CHH will be explained with reference to FIG. 30. R
F is a circuit for generating a rotating magnetic field Hr by passing a current with a phase difference of 90'' through the X and Y coils of the element CHI.SA
is the magnetoresistive element amplifier of element CHI. DR is +
Six or more circuits, which are drive circuits that flow current at predetermined timings to each functional conductor of the replicates related to bubble generation and swap related to write and read of the MBM device, are synchronized with the cycle and phase angle of the rotating magnetic field Hr. The operation is synchronized by a timing generation circuit TG.

(Rotating magnetic field distribution characteristics FIG. 31) FIG. 31 shows the rotating magnetic field distribution characteristics of the magnetic circuit PFC described above. That is, in the figure, the horizontal axis represents the length in the X-axis direction with the center of the magnetic circuit PFC shown in FIG. 8B as ○, and the vertical axis represents the rotating magnetic field strength Hx in the
When the rotating magnetic field strength Hx in the X-axis direction is shown when = O, a rotating magnetic field distribution characteristic as shown by curve I was obtained.

As is clear from the figure, a substantially uniform rotating magnetic field strength Hx is obtained within the range of -Xc to +XC, which is the distance between the opposing cores CO and R of the magnetic circuit PFC, and
Effective area of HI (minimum range to which rotating magnetic field should be applied) -
In the range of Xe to +Xs, a magnetic field strength uniformity of about ±2% was obtained. Note that the curve (2) indicated by a broken line is the rotating magnetic field distribution characteristic due to the magnetic circuit of the conventional configuration.

〔Effect of the invention〕

As explained above, according to the present invention, a magnetic bubble memory element is mounted on a flexible wiring board.

A space that generates a leakage magnetic field by being disposed in the space of the rotating magnetic circuit of the picture frame-shaped core, and by sandwiching the entire core within a rotating magnetic field confinement case made of a highly conductive material and electrically connecting its peripheral portion. can be made small, so a small VI
An extremely excellent effect can be obtained in that a magnetic bubble memory device with highly uniform rotation and a smaller and thinner overall shape can be obtained.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view showing the whole magnetic bubble memory device according to the present invention, FIG. 2A is a bottom view, FIG. 2B is a sectional view taken along line 2B-2B of FIG. 3, and FIG. 3 is a stacked structure. Figure 4 is a diagram explaining the board FPC, Figure 5 is an exploded perspective view showing the
The figure shows a board assembly BN in which the element CHI is mounted on the board FPC.
6 is a diagram showing the element CHI, FIG. 7 is a diagram illustrating lead bonding of the board assembly BND, FIG. 8 is a diagram illustrating the magnetic circuit PFC, and FIG. 9 is a diagram illustrating the magnetic circuit. A diagram explaining the manufacturing method of PFC, FIG. 10 is a diagram showing the inner case RFSb, and FIG. 11 is a diagram showing the outer case RFSa.
12 is an assembly diagram of the case RFS, and FIG. 13 is a diagram showing the board assembly BND and magnetic circuit F in the case RFS.
A cross-sectional view of the assembly containing the PC, Figure 14 is the magnet BI
FIG. 15 is a diagram explaining the configuration of M, FIG. 15 is a diagram explaining the bias coil, FIG. 16 is a cross-sectional view of an assembly in which a pair of magnets BIM and bias coil BIC are incorporated in the case RFS assembly, and FIG. 17 is a diagram explaining the structure of M. FIG. 18 is a diagram showing the outer shield case 5HIa, FIG. 18 is a diagram showing the inner shield case 5HIb, FIG. 19 is an assembly diagram of the shield case SHI, and FIG.
The figure shows a sectional view of the assembly shown in Fig. 16 assembled into the shield case 5) (I, Fig. 21 shows the packaging case PKG, and Fig. 22 shows the terminal fixing plate TEF.
FIG. 23 is a diagram showing the configuration of the contact pad, FIG. 24 is a cross-sectional view of element C) (I,
The figure shows the configuration of the magnetic bubble detector of element CHI,
FIG. 26 shows the configuration of the magnetic bubble generator GEN of element CHI, and FIG. 27 shows the swap gate SW of element CHI.
28 is a diagram showing the configuration of the replicate gate RF P of element CHI, FIG. 29A is a diagram showing the relationship between the bias magnetic field Hb and the holding magnetic field Hdc, and FIG. 29B is a diagram showing the relationship between the bias magnetic field Hb and the holding magnetic field Hdc. Figure 30 is a diagram showing the entire circuit of the magnetic bubble memory board. FIG. 31 is a rotating magnetic field distribution characteristic diagram. CHI...magnetic bubble memory element (element), FPC/
...Flexible wiring board (board), BND...board assembly, COI...drive coil (coil) -COR
...Picture frame core (core), PFC...magnetic circuit, RF
S...Rotating magnetic field confinement case (case), RFSa
...Outer case, RFSb...Inner case, BIM
...Magnet for generating bias magnetic field (magnet), BIMa
...Top magnet body, BIMb...Bottom magnet body, 1NM
... Inclined plate, MAG... Permanent magnet plate (magnet plate), H
OM...Magnetic adjustment plate, INN...Nonmagnetic inclined plate, BIC
... Bias magnetic field generation coil (bias coil),
SHI...External magnetic shield case (shield case)%SHI a...Outer shield case, 5HIb
...Inner shield case, PKG...Packaging case, TEF...Terminal fixing plate, GNP...Contact pad, 1...Element mounting section, 2.2a, 2b. 2G, 2d... bending portions, 3, 3a, 3b. 3c, 3d...External connection terminal connection section, 4, 4a. 4b---opening, 5.5a, 5b, 5c...perforation,
6... Board protrusion, 7... Base film, 8...
・Adhesive, 9a...Wiring lead. 9b...External terminal, 9c...Connection terminal, 9d...
・Symbol, 9e...index mark. 10...Cover film, 11...Tin plating layer, 1
2... Opening, 13... Solder plating layer, 14... Ponding pad, 15... Gold bump, 20a, 20
b+ 20c, 20d '' helix coil, 21
a, 21b... Connection point. 22a...X coil, 22b--Y coil, 23.
...Magnetic core, 24...Tap, 25...Wide groove, 26...Small width groove, 30...Aperture part, 3
1...Bending part, 32...Notch part, 33...
Squeezed part, 34... bending part, 35... notch part,
36... Polyimide film, 37... Adhesive, 3
8... Coil winding, 40... Winding wire, 51... Flat part, 52... Bent part, 53... Concave part, 54...
- Notch portion, 55... Flat portion, 56... Bent portion, 57... Recessed portion, 58... Notch portion, 59... Recessed portion, 60... Resin plate, 61... Through hole, 62...
Non-through hole, 63 mark. 64...Opening, 65...Groove, 66...Corner, IQ
l+ Fig. 4 C Fig. 4 Fig. 5 y Fig. 8 B Fig. 19 A SHI Fig. 19 B 211 Yadanku Fig. 21 B Tansu Fig. 22 A Fig. 22 B Fig. 22 C cL Deceased] ＼ Figure 26 Figure 28 of Q- Procedural amendment (voluntary) Indication of the case 1985 Patent application No. 66456 Name of the invention Person who makes magnetic bubble memory correction Relationship to the case Patent applicant name ( 510 Hitachi Ltd. Type
Address: 5-chome Marunouchi, Chiyoda-ku, Tokyo 100
Number 1 Hitachi, Ltd. Telephone fii212-1111
(Major representative) Target of amendment Full text of the specification Title of the invention Magnetic bubble memory Required range IRJ , a magnetic bubble memory element mounted on a flexible substrate,
A magnetic bubble memory characterized in that the coil, core, and magnetic bubble memory element are all sandwiched within a case made of a highly conductive material. DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a magnetic bubble memory, and particularly to a magnetic bubble memory suitable for reduction in thickness, size, and reduction in power consumption. Background] The magnetic bubble memory device, which has been in practical use for several years, uses a rotating magnetic field generated by a rectangular solenoid coil with an asymmetric structure on an E-shaped ceramic or synthetic resin wiring board on which a magnetic bubble memory chip is mounted. The structure is constructed by inserting the X coil and Y coil respectively and arranging them orthogonally. The X coil and Y coil have a structure in which they wrap not only the magnetic bubble memory chip but also a wiring board that is much larger than the chip, so the length from one end of each coil to the other becomes long, resulting in increased drive voltage and power consumption. In addition, since the X coil and Y coil require a uniform inductor balance in order to provide a uniform and stable in-plane rotating magnetic field to the magnetic bubble memory element, the coil shapes are different from each other and have an asymmetric structure. The structure had to be enlarged. Furthermore, a pair of permanent magnet plates that apply a perpendicular bias magnetic field to the magnetic bubble memory element and a magnetic shunt plate are arranged on the outer surfaces of these X coils and Y coils, and their peripheral parts are covered with a resin mold. Because of this structure, the stacking thickness in the vertical direction increases, which is an obstacle to the demand for thinner and smaller magnetic bubble memory devices. The closest prior art to the present invention known to the applicant is Patent Application Publication No. 55129 of 1974. This publication describes the structure of a frame-shaped core that surrounds a chip and a conductive magnetic field reflection box that completely surrounds them. However, no further specific structure is shown, and it is theoretically impossible to make an electrical connection to a chip completely surrounded by a conductor case from outside the conductor case without shorting it. Although it is possible, the description is clearly insufficient for people to think of putting it into practical use, including the fact that the method of attaching permanent magnets, magnetic shunt plates, bias coils, etc. is unknown. In other words, the embodiment of the present invention merely coincidentally coincides with the description in the above-mentioned publication in that a frame-shaped core is used as a result. [Object of the Invention] An object of the present invention is to provide a magnetic bubble memory that can be made thinner. Another object of the present invention is to provide a magnetic bubble memory that can be miniaturized by reducing the overall volume. Another object of the present invention is to provide a magnetic bubble memory with reduced power consumption. Another object of the present invention is to provide a magnetic bubble memory in which the inductance of the one-rotation magnetic field generating coil is reduced to reduce the VI product. Another object of the present invention is to provide a magnetic bubble memory in which assembly of component parts can be automated or facilitated. Another object of the present invention is to provide a magnetic bubble memory capable of increasing the number of connection terminals for input/output, etc., such as increasing capacity. Another object of the present invention is to provide a magnetic bubble memory in which the inclination angle of the magnetic bubble memory element with respect to the direction of the bias magnetic field can be set easily and with high precision. Another object of the present invention is to provide a magnetic bubble memory whose cassette can be made smaller. Still another object of the present invention is to provide a magnetic bubble memory in which peripheral circuits of the magnetic bubble memory device can be manufactured at low cost. SUMMARY OF THE INVENTION According to one embodiment of the present invention, a drive magnetic circuit using a frame-shaped core is provided. The magnetic bubble memory chip is disposed on a flexible wiring board so as to be surrounded by and substantially flush with the frame-shaped core. The drive magnetic circuit and the magnetic bubble memory chip are housed in a one-turn magnetic field confinement case made of a non-magnetic and highly conductive material. This configuration improves the uniformity of the rotating magnetic field and reduces the overall size. It can be made thinner. [Embodiments of the Invention] Next, the present invention will be explained in detail using the drawings. (Overview of overall structure Figures 1 and 2) Figures 1 and 2 (a) and (b) are diagrams for explaining an embodiment of the magnetic bubble memory device according to the present invention. FIG. 2(a) is a partially broken perspective view, FIG. 2(a) is a bottom view thereof, and FIG. 2(b) is a sectional view taken along line 2B-2B of FIG. 2(a). In these figures, CHI is a magnetic bubble memory chip (hereinafter referred to as a chip). In these figures, the chip CHI is omitted and only one chip is shown, but in the actual version, two chips are arranged side by side. shall be taken as a thing. (Chip yield is better with multiple chip configurations that match the total storage capacity than one large-capacity chip), F
The PC is equipped with two chips CHI and a chip C in the four corners.
COI is a flexible wiring board (hereinafter referred to as the board) that has a wire group extension for connecting the HI and external connection terminals.
is a drive coil (hereinafter referred to as a coil) that surrounds two chips CHI on almost the same plane and is arranged so that opposing sides are parallel to each other, and COR is a rectangular coil assembly CO.
It is a frame-shaped core (hereinafter referred to as the core) made of a fixedly arranged soft magnetic material that is provided so as to penetrate through the hollow part of I, and this core COR and each coil COI form a chip CH.
A magnetic circuit PFC that applies an in-plane rotating magnetic field to I is configured. The RFS is a rotating magnetic field confinement case (hereinafter referred to as the case) that houses the central rectangular portion of the substrate FPC, two chip CHs, and the entire magnetic circuit PFC. Case RFS is formed by processing two independent plates,
The upper and lower plates are electrically connected on the side of the case. A converging portion is formed in the peripheral portion so that the gap in the central portion is narrowed in a slightly wider range than the portion where the chip CHI is arranged. This constriction can also be used to position the magnet. Case PFS uses magnetic field confinement and soft substrate FP
It has the effect of killing two birds with one stone by mechanically supporting C. There is a gap SIR between the case PFS and the chip C) (I, especially on the side surface of the chip CHI, but this gap SIH, including the flat surface of the chip CHI, is coated or filled with silicone resin. Chip A passivation effect is intended to reduce the adhesion of foreign matter to the main surface during assembly and the intrusion of moisture into the chip main surface or side parts after assembly.If the outside of the case RFS is completely airtight, If it is possible to stop
Filling of resin SIR can be omitted, INM is case R
A pair of inclined plates made of magnetic material are placed on the outside of the FS. In Fig. 2, the upper inclined plate INM becomes thicker as it moves to the left, and the lower inclined plate INM becomes thicker as it moves to the right. Both have an inclined surface formed on the case RFS side. As a material for inclined plate INM. Soft ferrite, permalloy, etc. with high magnetic permeability μ and low coercive force Hc may be used. In this example, soft ferrite was selected because it is easy to process the inclined surface. MAG is inside the pair of inclined plates INM. A pair of permanent magnet plates (hereinafter referred to as magnet plates) placed overlapping the ROM
are a pair of magnetic shunt plates made of a magnetic material such as soft ferrite, which are arranged inside each of the magnet plates MAG and overlap therewith. The magnet plate MAG is formed to have a uniform thickness over the entire surface. The INN is a pair of inclined plates made of a non-magnetic material with good thermal conductivity such as copper, which are placed on the inner facing surfaces of the pair of magnetic shunt plates HOM and overlapped therewith. These inclined plates INN are formed to have substantially the same inclination angle as the inclined plate INM, and have inclined surfaces in opposite directions. Inclined plate INM, magnetic plate MAG,! ! Magnetic plate HOM and inclined plate IN
N is formed so that when stacked and arranged and integrated to form a bias magnetic field generating magnet body BIM (hereinafter referred to as magnet body), the thickness of the entire laminated magnet body is uniform over almost the entire surface. There is. A pair of magnets BIM are adhered to the central flat part surrounded by the constriction part of the case RFS. BIC is a bias magnetic field generating coil (
The bias coil BIC (hereinafter referred to as bias coil) is used to adjust the magnetic force of the magnet plate MAG to match the characteristics of the chip CHI, or to test for the presence or absence of unnecessary bubble generation defects. erase)
It is driven when SHI includes a case RFS that houses the board FPC on which the chip CHI is mounted and the magnetic circuit PFC, and a pair of magnet bodies BIMa and BI on the outside.
The materials of the shield case SHI, which is an external magnetic shield case (hereinafter referred to as shield case) made of magnetic material that houses Mb and bias coil BIC, are as follows:
High magnetic permeability μ. A magnetic material with a large saturation magnetic flux density Bs and a small He is preferable, and permalloy and ferrite have such characteristics. A nickel alloy was chosen. PKG is a packaging case made of a material such as AQ that has high thermal conductivity and is easy to process, and is attached to the outer circumferential surface of the shield case SHI by adhesion or fitting. GNP are contact pads extending from the four corners of the substrate FPC and arranged to contact external connection terminals folded back on the back surface of the shield case SHI. TEF is each contact pad G
This is a terminal fixing plate made of an insulating member that supports and fixes the NP at the stepped portion of the opening. REG is packaging case P
This is a resin molding agent that is sealed in the four inner corners of the KG and fixes the shield case RFS assembly inside the packaging case PKG. (Features of the overall structure, FIGS. 1 and 2) The features of the overall structure of the magnetic bubble memory device shown in FIGS. 1 and 2 are enumerated as follows. However, the features of this embodiment are not limited to these, and other features will become clear from the explanations that follow from Figure 3, but here we will explain the relationship between each oval part. The main features will be described below. (1) Make the rotating magnetic field generating coil PFC into a frame shape. Since the bubble memory chips CHI are arranged within the section on almost the same plane, the thickness of the entire bubble device can be reduced. With current mainstream technology, the top and bottom surfaces of the chip are
This is because the thickness of the entire device is a function of the sum of the chip thickness, the X coil thickness, and the Y coil thickness since the device is wound around the coil. (2) Since the X coil and the X coil are arranged on almost the same plane, there are the following effects compared to the conventional structure in which the X coil is wound on top of the X coil. ■The total winding length of the coil does not become long, so the inductance L can be reduced, making it possible to drive at low voltage and reduce power consumption. (2) The distance between the X coil and the X coil and the chip CHI can be made equal, and the magnetic field distribution can be made balanced. (3) Since the rotating magnetic field generating coil PFC is surrounded by the conductor case RFS, leakage of magnetic flux is reduced and drive efficiency for the chip CHI can be increased. (4) The conductor case PFS is a rotating magnetic field Hr generating coil P
It prevents the alternating current magnetic field generated from the FC from leaking to the magnet body BIM with a large magnetic permeability μ, and on the other hand, substantially blocks the passage of the direct current magnetic field of the bias magnetic field Hb that should be applied from the magnet body BIM to the chip CHI. There is an option not to. (5) Since the conductor case PFS is made of a material such as copper, which is harder than epoxy glass or the like conventionally used for wiring boards, it can mechanically support the chip CHI firmly. Therefore, especially when multiple chips are mounted in a configuration to increase manufacturing yield, variations in the inclination angle between chips have a large effect on magnetic properties, but according to this example, variations in the inclination angle between chips can be held small. (6) Flexible film board FPC as a wiring board
By using , the following effects can be obtained. Φ Substrate thickness can be reduced. ■Since the lead bonding method can be used, the thickness occupied by the bonding part can be reduced compared to the conventional wire bonding method. ■The effect of ■ above is due to the magnetic circuit gap (magnetic permeability μ
A bias magnet MAG having a small thickness or a small planar area can be used, which leads to a thinner overall device or a smaller planar area. ■Wiring from the chip CHI can be bent freely. Therefore, the terminal portion 1800 can be turned over, and the planar area of the entire device can be limited. ■The width of the opening for wiring out of the rotating magnetic field confinement case RFS can be made smaller. Therefore, leakage of the rotating magnetic field can be kept to a minimum. (7) Since the external wiring of the wiring board FPC is concentrated at the corners of the rectangle, the opening of the rotating magnetic field confinement case RFS can be provided at the corner where the influence is least. (8) Since the function of the inclined plate INN is not combined with the magnet or magnetization function, the following effects are obtained. ■Materials with good workability, such as copper, can be used to form the slope. ■Materials such as steel with good thermal conductivity can be used, and the heat generated by the rotating magnetic field generating coil COI can be efficiently dissipated. ■By using non-magnetic materials. It is possible to prevent the magnetic field passing through the magnetic shunt plate HOM from being disturbed. (9) It is preferable for the inclined plate INN to be as thin as possible in order to reduce the magnetic gap.Compared to the magnet MAG and magnetic shunt plate HOM, the inclined plate INN can be made thinner by limiting its width to the area necessary and sufficient for forming the inclined angle. This makes it easy to form an inclined angle in the thickness. (10) Since a plate INM made of soft ferrite having a large magnetic permeability μ is inserted between the magnet MAG and the shield case SHI, the magnetic gap therebetween can be filled. The plate INM also contributes to heat radiation. Board I
Since a material having a coercive force Ha smaller than that of the magnet MAG is selected as the NM, the effective thickness of the permanent magnet can be kept uniform. (11) Since the shield case SHI is made of a magnetic material such as permalloy with a high magnetic permeability μ, the magnetic resistance of the magnetic circuit using the magnet MAG as the magnetic field source can be reduced.
The thickness and planar area of the magnet MAG can be reduced. (12) Since the shield case SHI is made of a magnetic material such as permalloy with a high saturation magnetic flux density Bs, it has the function of bypassing external magnetic field noise and preventing it from being transmitted to the chip CHI. (13) The above (11) and (12) each lead to reducing the thickness of the shield case SHI. (14) Since the shield case SHI uses an iron-nickel alloy such as permalloy, it is suitable for bending and protects the parts incorporated therein against external mechanical forces. (15) Rotating magnetic field generating coil PFC and bias coil B
Since both ICs are core-type, the storage efficiency or packaging density within the packaging case SHI or PKG can be increased. (16) Since the case RFS is inserted between the core 〇OR and the magnetic shunt plate HOM, the interval between them can be finely adjusted by the thickness of the rotating magnetic field confinement case RFS and the bending angle in addition to the thickness of the coil COI. can. The shorter this distance is, the smaller the overall planar size can be, leading to lower power consumption by reducing the coil length. However, if the distance is too short, the DC bias magnetic field Hb from the magnet MAG will leak to the core 0OR having high magnetic permeability, and the uniformity of the bias magnetic field around the chip will deteriorate. Therefore, this distance is very critical due to the above-mentioned characteristics, and the single-piece structure allows for precise adjustment. (17) Since the constriction portion is provided around the rotating magnetic field confinement case RFS, alignment of the magnet body BIM is easy. (18) The inclined plate INN is made by arranging two plates made under the same manufacturing conditions so that there is a rotation angle difference of 180° between the top and bottom surfaces of the chip, so that the two plates are made under the same manufacturing conditions. A pair of magnetic shunt plates HOM and a pair of magnets M are arranged.
AG can be aligned almost parallel. (Overview of assembly Fig. 3) Fig. 3 is an assembly perspective view for explaining the procedure for stacking and assembling each component constituting the above-mentioned magnetic bubble memory device, and the same reference numerals as above indicate the same members. . In the same figure, first, a board F has connection parts for input/output wiring protruding from the four corners and an element mounting part in the center.
Board assembly BN with two chips CHI mounted on a PC
D is placed inside an outer case RFSa with an insulating sheet adhered to the position indicated by the dotted line on the bottom surface, and after a magnetic circuit PFC is incorporated on this board FPC, silicone resin 5IR (not shown) is filled. The inner case RFSb is assembled into the outer case RFSa in the upper part, and the side contact portions of the outer case RFSa and the inner case RFSb are electrically connected by soldering or the like. After arranging the upper magnet body B I Ma and the lower magnet body BIMb in the concave constriction provided on the outer surface of the The aligned bias coil BIC is arranged in a gap (not shown), and these are housed in the outer case 5HIa.The inner case 5HIb is further assembled, and the side contact portions of the outer case 5HIa and the inner case 5HIb are welded or the like. Magnetically connected primary inner case 5HI
The external connection terminal connection parts of the board FPC protruding from the four corners of the board FPC are folded back on the back surface of this inner case 5HIb as shown in FIG. Terminal fixing plate T with contact pads COP (not shown) mounted in each opening on each external connection terminal covered with solder etc.
The EFs are arranged in contact with each other, and each external connection terminal and the contact pad COP are electrically connected by soldering or the like by thermocompression bonding or the like. Next, these assembled bodies are housed in a packaging case PKG, and sealed with a hermetic seal or the like at the contact portion between the terminal fixing plate TEF and the packaging case PKG, and then assembled. Next, the structure of each component mentioned above will be explained. (Flexible wiring board Fig. 4) Fig. 4 is a diagram showing a board FPC, where A is a plan view thereof and B is a layout in which the connection parts of external connection terminals protruding from the four corners are folded back and combined. Plan view C is an enlarged cross-sectional view of 4C-4G of figure A, and the same figure is 4D- of figure A.
It is a 4D enlarged sectional view. In the same figure, the board FPC is
There is a square element protection part 1 in the center, small bent parts 2 (2a, 2b, 2a, 2d) at the four corners, and a square external connection terminal connection part (hereinafter referred to as connection part) at the tip. ) 3 (3a, 3b, 3c, 3d), and the overall shape is approximately windmill-shaped and is integrally formed. rectangular openings 4 (4a, 4b) with double frame structure to which chips CHI are mounted and their terminals connected, and 3 for positioning.
perforations 5 (5a, 5b, 5c) are provided, and one
A substrate protrusion 6 for positioning is provided at the tip of each connecting portion 3c. In addition, as shown in FIG. C, this FPC board is made by forming a copper thin film on a base film 7 made of a polyimide resin film with a thickness of about 50 μm, for example, via an epoxy adhesive 8, and then applying the copper thin film to the desired shape. By etching into a pattern shape, wiring leads 9a as shown in FIG.
A circular external terminal 9b and an oval coil lead connection terminal 9c. Patterns such as symbols 9d and index marks 9e are formed, and a transparent or semi-transparent cover film 10 is adhered to the upper surface of these through an adhesive 8 made of the same material as described above. And this board FP
In the opening 4 of C, an opening with highly accurate dimensions is formed in the base film 7 on which the chip CHI (not shown) is mounted, and an opening with relatively large dimensions is formed in the cover film 10 on the upper surface side. Further, a wiring lead 9a is exposed between the base film 7 and the cover film 10, and a tin plating layer 1 is formed on the surface of the wiring lead 9a.
1 is formed, and the opening shape is formed to have a two-layer structure and a double frame structure. On the other hand, in the connecting portion 3, as shown in the figure, a circular opening 12 is formed at a portion of the cover film 10 corresponding to the circular external terminal 9b and the oval external terminal 9c (not shown). External terminal 9 exposed from
A solder layer 13 is formed by plating or dipping on the copper film patterns b and 9c. The external terminals 9b, 9c provided on these connecting portions 3 are the respective connecting portions 3a, 3b, 3c, 3d and the bent portion 2a. 2b, 2c, 2d and each wiring lead 9a formed continuously on the element protection part 1, and these wiring leads 9a are connected to each opening 4a provided in the element mounting part 1,
Each connection part 3a, 3b, 3c, 3d is attached to a part of the open end of 4b.
are gathered in blocks and their tips are connected to each opening 4a, 4.
exposed within b. That is, as shown in FIG.
The wiring lead 9a of the connecting portion 3b is located at the lower left of the opening 4b, the wiring lead 9a of the connecting portion 3c is located at the upper right of the opening 4a, and the wiring lead 9a of the connecting portion 3d is located at the lower right of the opening 4b. are wired to each. And this board F
In the PC, each of the connecting parts 3a, 3b, 3c, and 3d becomes each bent part 2a in a subsequent process. Each external terminal 9b is bent at 2b, 2c, and 2d and assembled as shown in FIG. B to form a solder layer 13,
9c is exposed on the surface, and wiring lead 9a, symbol 9
Since the surfaces of the index mark d and the index mark 9e are covered with the cover film 1o, these patterns are configured so that they can be easily read through the cover film 10. In such a configuration, the substrate FPC uses a polyimide resin film, and each bent portion 2 is provided at the four corners of the element protection portion 1.
Each connection 3a, 3b, 3 via a, 2b, 2c, 2d
c, 3d, and each of these connecting parts 3
By folding and combining a, 3b, 3c, and 3d to form the external terminal section, the element protection section 1 and the connection section are separated into two parts.
Since it has a layered wiring structure, the area of the element protection part 1 can be increased without reducing the area of the connection part 3, and at the same time, it is possible to increase the number of external terminals, and the overall shape can be made smaller. . In addition, in such a configuration, the wiring leads 9a from each external terminal 9b to each opening 4a, 4b of the element protection part 1
Since the time can be significantly shortened, the influence of external noise etc. can be significantly reduced. That is, signals with a high S/N ratio can be input and output. Furthermore, a board protrusion 6 is provided at one end of the connecting part 3c, and an index mark 9e is provided on this protrusion 6, so that when the board is folded back and assembled, it can be used for displaying the central part of the board.
I (see Figure 2) can be used for positioning when assembling, distinguishing the type of wiring lead 9a, or displaying the product model. It can be streamlined. Additionally, holes 5a, 5b, 5c are provided at both ends of the element protection portion 1 of the FPC board.
By providing this, it becomes easy to distinguish between the left and right sides of the FPC board, position the chip CH, etc., and similarly, it is possible to streamline assembly. (Substrate Assembly Figures 5.6.7) Figure 5 shows a plan view of the chip CH mounted on the FPC substrate described above. In the same figure, the board FPC
In the element mounting part 1, two chips CHI are placed in the opening 4a,
A board assembly BND is constructed by being mounted in parallel between the chips CHI and IMb, and one of the chips CHI is constructed by integrating two blocks of IMb chips, as shown in the enlarged plan view in FIG. Two chips CHI constitute 4 blocks, a total of 4 Mb chips. In one block of the chip CHI shown in FIG. 6, thick lines indicate conductor patterns and thin lines indicate chevron pattern transfer paths, respectively. The chip CHI shown in FIG. 5 also has bonding pads 14 provided by gold plating on the ends of the chip CHI and a substrate as shown in enlarged cross-sectional views in FIGS. 7A and 7B, respectively. A gold bump 15 is interposed between the wiring lead 9a formed with the tin plating layer 11 in the FPC opening 4, and lead bonding is performed using Au-Sn eutectic using a thermocompression bonding method. According to such a configuration, the openings 4a, 4 of the substrate FPC
The wiring lead 9a of b and the bonding pad 14 of the chip CHI are connected by lead bonding using AuSn eutectic, and the chip CHI can be supported and fixed, so the connection strength can be greatly improved and the thickness can be reduced. . In addition, since the surface of the chip CHI is covered with the element mounting portion 1 of the FPC board, the surface of the chip CHI is protected, and handling properties can be improved, and the mechanical strength of the FPC board can be maintained. . Also, according to such a configuration. Each chip CHI consists of 2 blocks, and 2 chips C
Because HI consists of 4 blocks. Each connection part 3a is the closest to each block. Wiring can be distributed to 3b, 3c, and 3d, and symmetry of chip CHI arrangement can be obtained, making testing, inspection, etc. extremely easy. Furthermore, four connection parts 3a, 3b, 3c,
3dt- is provided, so wires such as the magnetic bubble detector DET and maple loop of each chip CHH are distinguished from other functional wires and concentrated at one connection point, and this connection point is selected at a location away from the noise source. By arranging them as such, input/output signals with extremely low noise can be exchanged. (Drive Magnetic Circuit FIGS. 8 and 9) FIG. 8 is a diagram showing the magnetic circuit PFC, and FIG. 8A is a perspective view, and FIG. 8B is a plan view showing the drive magnetic circuit. In the figure, the magnetic circuit PFC is. The coil COI is made up of four sets of coils 20a, 20b, 20c, and 20d by winding in the direction of the arrow on mutually parallel opposing sides of a frame-shaped core COH made of a soft magnetic material.
are wound, and the coils 20a and 20 on opposite sides
B is wound in series through the connection point 21b to form the X coil 2.
2a is wound in series with coils 20c and 20d via a connection point 21a to form a Y coil 22b. Then, currents 1x and Iy (for example, triangular non-current) whose phases are different by 90 degrees are applied to the X coil 22a and the Y coil 22b.
As shown in Figure B, a leakage magnetic field Hx is generated in the X-axis direction and a leakage magnetic field Hy is generated in the y-axis direction.
It is supplied as a rotating magnetic field to the two chips CHI mentioned above. Moreover, the magnetic circuit PFC configured in this way is as follows. As shown in a perspective view in FIG. 9, windings are wound in series on a rectangular parallelepiped magnetic core 23 made of a soft magnetic material, with taps 24 provided for each block, and wound in series to form a pair of coils, for example coils 20a and 2. After forming a pair of X coils 22a consisting of °Ob, a wide groove 25 having a constant width and a narrower groove 26 are cut between each coil 20a and 20b, and then The wide grooves 25, which are cut from the narrow groove 26 and divided into two parts, are combined and glued together in directions orthogonal to each other to form a picture frame shape as shown in FIG. In addition, on the contrary, the wide groove 2 mentioned above
5 and a rectangular parallelepiped core 2 with a narrow groove 26 formed in advance.
3, coils 20a and 20b may be wound through taps 24 to form a pair of X coils 22a. Furthermore, the pair of Y coils 22b described above are formed in exactly the same manner. In such a configuration, the coils 20a and 20b are wound in series around the rectangular parallelepiped magnetic core 23 with taps 24 provided, so when assembled as shown in FIG. 8, the wires are connected by crossing each other ( connection points), and the winding routing can be simplified. According to such a configuration, the X coil 22a and the Y coil 2
2b has a symmetrical structure, resulting in a rough coupling,
The inductance balance is improved, and magnetic interference between magnetic bodies due to leakage magnetic fields can be prevented. Further, since the magnetic circuit PFC has a frame-shaped structure that is not placed on the upper or lower surface of the chip CHI, the thickness in the stacking direction is reduced, making it possible to reduce the thickness. (Rotating magnetic field confinement case Fig. 10.11.12) 1st
Figure 0 is a diagram showing the case RFS, and Figure A is a plan view.
Figure B is a sectional view taken along the line 10B-10B. In the figure, the inner case RFSb has a frame-shaped constriction part 30 whose central part is concave, and whose opposing end sides extend upward by approximately 90 degrees.
The case RFSb is composed of a bent part 31 bent at 0 degrees and notched parts 32 cut diagonally at each of its four corners, and the case RFSb is made of a highly conductive material. For example, it is formed by pressing an oxygen-free copper plate. In this case, the constricted portion 30 and the bent portion 31 can improve the mechanical strength of the inner case RFSb in the torsion direction, and can appropriately limit the outer diameter dimensions in the longitudinal and lateral directions between the bent portions 31 facing each other. . Further, the aperture section 30 can appropriately adjust the distance between the magnet body BIMb arranged on the outer surface side of the case RFSb and the chip CHI arranged on the inner surface side. Note that the cutout portions 32 provided at the four corners are each bent portion 2a of the board FPC disposed within this case RFSb. It forms the drawer parts 2b, 2c, and 2d. According to such a configuration, the inner case RFSb can be formed by a press working method, and therefore can be manufactured with high precision dimensions and at low cost. Note that, although oxygen-free copper is used for the inner case RFSb, a plate material made of copper, silver, gold plate, or an alloy plate thereof may be used. FIG. 11 is a diagram showing an outer case RFSa corresponding to the above-described inner case RFSb, with FIG. 11A being a plan view and FIG. 11B being a sectional view taken along line IIB-11B. In the same figure,
This outer case RF Sa is similar to the inner case R described above.
It is formed using the same material and manufacturing method as FSb, and its structure is almost the same as described above, with a frame-shaped constriction part 33 whose center part is concave, and the opposite end thereof is bent upward at approximately 90 degrees. It is configured to include a bent portion 34 and a notch portion 35 cut diagonally at each of its four corners. In this case, the mutually opposing bent portions 34 are formed so that the inner dimensions thereof are approximately the same as the outer dimensions between the bent portions 31 of the inner case RFSb described above, and the height H is increased. has been done. Note that the constriction portion 33 and the notch portion 35 are connected to the inner case RF described above.
It is formed to have substantially the same dimensions as Sb. The outer case RFSa and the inner case RFSb configured in this way are shown in a plan view in FIG. 12A and in FIG. 12B.
As shown in the cross-sectional views 12B-12B, the inner case RFSb is inserted into the outer case RFSa, and the outer surfaces of the bent portions 31 of the outer case RFSa are brought into contact with each other and connected, thereby integrating the case RFS and assembling the case RFS. It will be done. (Case assembly Figure 13) Figure 13 shows the board assembly BND inside the case RFS mentioned above.
This figure shows a cross-sectional view of the storage arrangement. In the same figure, a polyimide film 36 having a thickness of about 0°111ffi+, for example, is adhesively arranged as an electrically insulating sheet on the bottom surface of the outer case RFSa.
A board assembly BND is placed on top, and a magnetic circuit FPC is placed on the periphery of the board assembly BND.
After applying an epoxy adhesive 37 to the upper surface of D, an inner case RFSb is inserted into the upper part of these and arranged to be joined. In this case, the inner surface of the bent portion 34 of the outer case RFSa and the outer surface of the bent portion 31 of the inner case RFSb are electrically and mechanically joined by metal flow, soldering, etc. at the portion indicated by the X mark. Further, a gap between the outer case RFSa and the inner case RFSb is filled with silicone resin SIR, and the board assembly END and the magnetic circuit PFC are fixedly arranged. In this case, the bent portions 2 (
2a, 2. b, 2c, 2d) are drawn out. 38 is a lead wire for connecting the coil COIs or connecting the coil COI and the external terminal 9G provided on the board FPC. In such a configuration, when a leakage magnetic field is generated by driving the magnetic circuit FPC, an induced current flows through the case RFS to form a closed loop, and this induced current confines the rotating magnetic field within the case RFS, so that the chip CHI A uniform rotating magnetic field is applied to the substrate p.
Chip CHI installed in PC. Since the magnetic circuits PFC are sandwiched and disposed within the convex portions of the peripheral portion, the packaging effect can be improved and the ease of assembly can be greatly improved. Furthermore, by reducing the volume covered by the outer case RFSa and the inner case RFsb, the VI product (volume) can be reduced, and the magnetic circuit PFC that generates one rotation of the magnetic field can be downsized. Furthermore, the outer case RFSa and the inner case RFSb are provided with concave portions formed by constricted portions 30.33, and by reducing the gap between the opposing concave portions, the rotating magnetic field has a component perpendicular to the plane of the chip CHI (Z
component) is close to zero and there are only horizontal components, and uniformity can be improved. (8 stone body Figure 14) Figure 14 is a diagram showing the magnet body BIM, in which Figure A is a plan view, Figure B is a side view, and Figure C is a front view. In the figure, the magnetic body BIM includes an inclined plate IN made of a non-magnetic material, such as copper, and one of the opposing surfaces has a predetermined inclined surface.
N, a first magnetic shunt plate HOM having a uniform plate thickness disposed on the inclined surface side of this inclined punching NN, and this first magnetic shunt plate HOM
□ A magnet plate MAG with a uniform thickness placed on the upper surface side and a second magnetic shunt plate HOM having an inclined surface on the upper surface side of this magnet plate MAG are sequentially laminated and integrated with an epoxy adhesive. The laminated plate thickness is uniform over almost the entire surface. A uniform magnetic field for generating a bias magnetic field is emitted from the upper and lower surfaces of this magnet body BIM over almost the entire surface.6 (Bias Coil Figure 15) Figure 15 is a diagram showing the bias coil BIC. A is a perspective view, and B is a cross-sectional view taken along line 15B-15B. In the same figure, the bias coil BIC has a winding 40 whose outer surface is coated with an insulating member such as a thermosetting resin, and is wound in an array with a cross section of 5 x 4 wires so that the overall shape has a picture frame shape. After that, it is crimped by heat welding, cooled, and formed into a frame shape of a predetermined value. In this case, the thermosetting resin coated on the outer surface of each winding 40 is thermally welded to each other, and each winding 40 is clogged and formed by pressure bonding, and by cooling, each winding 40 is hardened in a bundled state. Therefore, it is formed into a predetermined picture frame shape. (Mounting the magnet and bias coil on the case assembly
(FIG. 16) FIG. 16 is a sectional view of the case RFS assembly described in FIG. 13 incorporating the magnet body BIM and bias coil BIC. In the same figure,
An upper magnet body B I M a and a lower magnet body B I M b p are adhesively arranged on the upper and lower surfaces of the case RFS assembly, which houses the board assembly BND and the magnetic circuit PFC inside, and further this upper magnet body B A bias coil BIC is housed in a frame-shaped groove formed by being surrounded by the peripheral edge of IMa and the bent portion 31 of the inner case RFSb. In this case, the upper magnet body B I M
a and the lower magnet body BIMb are made of exactly the same material and two dimensions, and the inclined plate INN side of these magnet bodies BIMa and BIMb is connected to the constricted part 30 of the inner case RFSb.
The concave portion surrounded by the concave portion and the constricted portion 3 of the outer case RFSa
They are arranged in close contact with each other within the concave portions surrounded by 3. In such a configuration, a pair of magnet bodies BIMa,
Since the BIMb is placed and the bias coil BIC can be placed in the frame-shaped groove formed on the periphery of the BIMb,
The overall thickness of each component in the stacking direction is reduced, making it possible to make it smaller and thinner. In addition, the outer case RF Sa
A frame-shaped space groove is formed between the outer edge portion of the lower magnet body BIMb, and the bias coil BIC is inserted into this portion.
Alternatively, a new bias coil may be provided, and furthermore, a bias coil may be formed by winding a wire as a coil bobbin. (Magnetic shield case Fig. 17, 18, 19) Fig. 17
The figures show the shield case SHI, with figure A being a plan view and figure B being a 17B-17B cross-sectional view thereof. In the same figure, the outer shield case S HI a has a flat portion 51 and an end side opposite to the flat portion 51 that extends upward by approximately 90 mm.
The folded part 52 that is folded back at the same time, and the folded part 52
a recess 53 partially cut out in the center of the
The shield case SHIa is made of a material having high magnetic permeability, high saturation magnetic flux density, and preferably high thermal conductivity, such as a notch portion 54 whose corner is cut diagonally. It is formed by pressing a permalloy plate. FIG. 18 is a view showing an inner shield case 5HIb corresponding to the above-mentioned outer shield case 5HIa, with FIG. 18A being a plan view and FIG. 18B being a cross-sectional view taken along line 18B-18B. In the same figure, this inner shield case SHI b
is formed using the same material and manufacturing method as the above-mentioned outer shield case S HI a, and its structure is almost the same as above, with a flat part 55 and an opposite edge of the flat part 55 extending upward at approximately 90 degrees. A folded portion 56 and a recessed portion 57 partially cut out in the center of the bent portion 56.
and a notch 58 cut diagonally at each of its four corners.
It is composed of: In this case, the mutually opposing bent portions 56 have an outer dimension approximately equal to the inner dimension between the bent portions 52 of the outer shield case SHIa described above, and have a reduced height H. It is formed by The outer shield case 5HIa and the inner shield case 5HIb configured in this way are shown in a plan view in FIG. 19A and in a cross-sectional view taken along the line 19B-19B in FIG. 19B. Insert 5HIb and open the outer shield case S H
Spot welding or solder welding is applied to the recess 59 formed by the recess 53 of Ia and the recess 57 of the inner shield case 5HIb, and the outer shield case SHI a is assembled by magnetically and mechanically fixing the recess 59. It will be done. In such a configuration, the outer shield case 5HIa
By setting the bent portion 52 of the inner shield case 5HIb and the bent portion 56 of the inner shield case 5HIb in the lateral direction, that is, in a direction that intersects with the laminating direction, by aligning them in the laminating direction, the lateral dimension can be reduced, making it compact. In addition, high integration of component parts becomes possible. (Magnetic shield case assembly FIG. 20) FIG. 20 shows the case RFS assembly, which incorporates the board assembly BND and magnetic circuit FPC inside the shield case SHI assembly described in FIG. magnetic plate BIM
Fig. 3a shows a cross-sectional view incorporating an assembly consisting of BIMb and bias coil BIC. In the figure, inside the outer shield case SHI a, there is an upper magnet body B I M a from the bottom side to the center, a bias coil BIC at the periphery, and a case RFS assembly (board assembly BND inside, magnetic After sequentially stacking the lower magnet body B (in which the circuit PFC etc. is incorporated) and the lower magnet body B IMb,
Insert the inner shield case 5) (Ib) and seal by welding and fixing in the recess 59 (see Fig. 19) formed by the recess 53 of the outer shield case SHIa and the recess 57 of the inner shield case 5HIb. In this case, by filling the shield case SHI with grease or the like, the internal components will come into close contact with each other, and the heat generated from the case RFS will be able to penetrate the shield case SHI. In addition, the heat dissipation effect can be improved by making the case RFS and the shield case 5I (I) contact each other on their sides by press-fitting.In such a configuration, the outer shield case S HI
By stacking the case RFS assembly on the bottom side of the case RFS a so that the bent parts 31 and 34 thereof face each other, each component stacked between the outer shield case S HI a and the inner shield case 5 HI b is brought into close contact with each other. Since it can be arranged, it can be made smaller and thinner, and a heat dissipation effect can be obtained at the same time. (Packaging case FIG. 21) FIG. 21 is a diagram showing a packaging case PKG, in which FIG. 21A is a plan view and FIG. 21B is a 21B-21B sectional view thereof. In the figure, the packaging case PKG is formed by drawing a material 1 with good thermal conductivity, such as an aluminum plate with a thickness of about 0.5 mm, and has a black coating on its outer surface (not shown). There is. This packaging case PKG includes the outer shield case 5.
The shape of HIa can be improved and used for both purposes. In such a configuration, this packaging case P
The KG serves as an outer case after the magnetic bubble memory device is completed and also functions as a heat sink, and its inner corner also functions as a mold during resin molding by the potting method described later. (Terminal fixing plate and contact pad Fig. 22.23)
FIG. 22 is a diagram showing the terminal fixing plate TEF, in which FIG. 22A is a plan view, FIG. 22B is a sectional view taken along line 22B-22B, and FIG. 22C is a rear view thereof. In the same figure, the terminal fixing plate TEF is made of an electrically insulating material, for example, a glass epoxy resin plate 60, and its external shape is such that it can be freely inserted into and removed from the opening of the packaging case PKG. The resin plate 6 is formed to have dimensions in the direction.
A large number of through holes 61 are formed in a matrix arrangement at predetermined intervals in the vertical and horizontal directions except for the peripheral area of 0, and the corners of these through holes have cross sections that are not rotationally symmetrical. A concave non-through hole 62 is provided, and a mark 63 made of, for example, a white coating film for locating directionality or features is attached inside the non-through hole 62. In addition, a large number of through holes 6 are formed in this resin plate 60.
As shown in FIG. 1B, large-diameter openings 64 are coaxially communicated with each other on the back side of the plate, and all of these openings 64 have a depth of about 60% of the plate thickness. In addition, it communicates with the through hole 61 with a step in the middle. Also,
As shown in Figure C, the back side of this resin plate 60 has a depth approximately equal to the depth of the opening 64 along its peripheral portion, and has a different width in the plane direction and a concave cross section. A groove 65 is formed, and the above-mentioned coil CO is placed inside this groove 65.
It constitutes a passage section and a connection section for the winding of I and the winding of bias coil BIC. In addition, the corner portion 6 of this resin plate 60
6 does not have a concave shape, has a predetermined thickness, and has a contact surface with the inner surface of the packaging case PKG described above. In this way, the back side of the resin plate 60 is formed to have a two-tiered structure with different plate thicknesses. FIG. 23 is a diagram showing the contact pad GNP, with FIG. 23A being a plan view and FIG. 23B being a sectional view taken along line 23B-23B. In the figure, the contact pad GNP is formed by forming a nickel plating layer 71 on the surface of a piece 70 punched out of a highly conductive material, for example, a copper plate with a thickness of about 0°5III11 by press working. It is constructed by forming a gold plating layer 72. (Final assembly FIG. 20.4.2) For each component configured in this way, first, the shield case assembly described in FIG. 20 is inserted into the packaging case PKG described above. In this state, each connection part 3B, 3b, 3c, 3d of the board assembly BND is connected from the four corners of this packaging case PKG (Fig. 4A).
(see) is about 9 from each bending part 2a, 2b, 2c, 2d.
Next, the four corners of the packaging case PKG are bent at 0 degrees and protruded, and resin molding is performed by a botting method to fix each individual component within the packaging case PKG. Subsequently, these connecting portions 3a, 3b, 3c, and 3d are connected to the corresponding bent portions 2a,
2b, 2c, and 2d are further bent at about 90 degrees and attached to the outer surface of the inner shield case 5HIb with adhesive.
After combining as shown in Figure B, the terminal fixing plate TE
A contact pad GNP is mounted in each opening 64 on the back side of F, or the side surface of the contact pad GNP is further fixed with adhesive and inserted into the packaging case PKG, and each connection part 3 aw 3 b y 3 c e3d
8 in this case, each connection portion 3a. Since the arrangement pitch of each external terminal 9b provided in 3b, 3c, and 3d matches the arrangement pitch of each contact pad GNP, each external terminal 9b and contact pad GNP are in electrical contact. Next, from the back side of the terminal fixing plate TEF placed, each through hole 61
For example, by inserting a heating element with a thin tip into the contact pad GNP and thermocompressing the contact pad GNP, each external terminal 9b and the corresponding contact pad GNP are electrically connected, and the terminal fixing plate TEF is also mechanically connected at the same time. After fixing, the magnetic bubble memory device shown in FIG. 2 is completed. (Magnetic bubble memory element No. 24.25.26, 27.
Figure 28) Figure 24 shows the above-mentioned magnetic bubble memory chip C.
It shows a cross-sectional view of the vicinity of the bonding pad PAD of HI. In the same figure, GGG is gadoliniu
m-gallium-garnet substrate, L
PE is a bubble magnetic film formed by liquid phase epitaxial growth, and an example of its composition is shown in Table 1 below. Table 1 1ON shows the ion implantation layer formed on the surface of the LPE film to suppress hard bubbles. The SPI is the first spacer, eg, 3000 nm thick S i O, formed by a gas phase chemical reaction. CND1 and CND2 indicate two conductor layers, which have the function of controlling bubble generation, copying (splitting) and exchange, which will be described later, and the lower first conductor layer CND1 is
The second conductor layer CND2 on the top g is made of a material such as AU. SF3 and SF3 are interlayer insulating films (second and third spacers) made of polyimide resin or the like that electrically insulate the conductor layer CND and the transfer pattern layer P formed thereon, such as permalloy. PAS is a passivation film made of a SiO□ film or the like formed by a vapor phase chemical reaction method. PAD indicates a bonding pad of the chip CHI, and a thin connector wire such as an Al wire is bonded here by thermocompression bonding or ultrasonic bonding. In this bonding pad PAD, the lower first layer PAD is Cr, the middle second layer PAD is Au layer, and the upper third layer PAD is Cr.
A D3 is formed of a material such as an Au plating layer, and the second layer PAD and third layer PAD3 are made of Cr, C, etc.
It may be formed of a material such as u. P indicates a layer used for a bubble transfer path, a bubble division 1 generation, exchange and detection section, and a guardrail section, and in the following description, it will be expressed as a transfer pattern layer for convenience. In the example of FIG. 24, this transfer pattern layer P is attached to the lower layer P, F
Although e-Ni is used for the upper layer P2 and Fe-Ni is used for the upper layer P2, as described above, it is also possible to interchange the two materials vertically. Hereinafter, an example in which the transfer pattern layer consisting of multiple layers described above is applied to each part of the chip CHI will be explained using the plan views from FIG. Figure 25 shows the bubble detector part, where MEM is the main magnetoresistive element, and the bubbles stretched horizontally in a strip shape are shown in Figure 25. The presence or absence of a bubble is detected by utilizing the change in resistance value when passing through it. MED is a dummy magnetoresistive element having a pattern similar to that of the main magnetoresistive element MEM, and is used to detect noise components due to the influence of a rotating magnetic field. Above the main magnetoresistive element MEM, several ten stages of bubble stretchers ST are formed, although only two stages are shown, which stretch the bubbles laterally and transfer them downward. Note that PR indicates the bubble transfer direction. ER is a bubble eraser, and when a bubble reaches the conductor layer CND, it is erased. A guardrail GR consisting of three rows of pattern groups is provided around this detector and between the dummy and main detection.
It is designed to expel unnecessary bubbles generated inside the guardrail GR to the outside thereof, and prevent unnecessary bubbles generated outside the guardrail GR from entering inside it. In addition. In the plane pattern diagrams shown in FIG. 25 and subsequent figures, patterns other than the conductor layer CND indicate the transfer pattern layer P explained in FIG. 24. In the figure, the signal-to-noise ratio (S,
/N ratio) was improved. For example, when a three-layer permalloy layer with a 5in2 film interposed between each layer is used as a transfer pattern. As shown in Table 2 below, S
/N ratio can be improved by two times or more. Table 2 Furthermore, the performance of the guardrail GR is also improved, such as by increasing the removal rate of unnecessary bubbles due to the reduction in the holding force Hc. FIG. 26 shows a magnetic bubble generator GEN in which the transfer pattern layer P is multilayered. The current generated by magnetic bubbles can be reduced. It has become possible to extend the life of the conductor layer CND of the magnetic bubble generator. Therefore, a semiconductor element with a small current capacity value can be used for the drive circuit of the conductor layer CND, and the cost can be reduced. FIG. 27 shows a swap gate section formed by a writing major line WML formed by a transfer pattern array such as minor loops m, Pw, ~Pw3, etc. formed by transfer patterns such as P a - P h, and a hairpin-shaped conductor layer CND. It shows. In the same figure, P7 is the same as the transfer pattern P7 in the bubble generator GEN of FIG. Transferred to WML. When a current is applied to the swap conductor layer CND, the magnetic bubble of the transfer pattern Pd of the minor loop m is transferred to the transfer pattern Pw of the major line WML through the transfer patterns PΩ and Pm, and the magnetic bubble from the major line Pw is transferred to the transfer pattern Pw of the major line WML. The bubble passes through transfer patterns Pk, Pj, and Pi to transfer pattern P of the minor loop.
The data is transferred to e and the bubbles are exchanged, that is, the information is rewritten. Note that the rightmost minor loop md is not provided with a swap gate, but this is a dummy loop in which no magnetic bubble is injected to reduce the peripheral effect. In this way, the transfer pattern layer P at the exchange position
By multilayering i-Pm, magnetic bubbles can be exchanged with a small current value. Further, as shown in FIG. 28, a magnetic bubble copying machine, that is, a divider, can be driven with a small current value as well. In the same figure, one normal magnetic bubble is Pn~P g t P s
-P
. and is transferred to the read major line RML. (Holding magnetic field and rotating magnetic field FIG. 29) Magnet plate MAG is arranged at an angle of about 2 degrees with respect to chip CHI. This is the bias magnetic field Hb for the chip CHI.
The holding magnetic field Hdc is applied with a slight deviation from the vertical direction, thereby improving the start and stop margins of bubble transfer by approximately 6 Oe.
(Figure 29A). As shown in Figure 29A, the magnet body BIM and the chip CHI
Due to the inclination of the angle θ with , the DC magnetic field Hz has a component Hdc in the xy plane. Then, the magnitude of this in-plane component Hdc is Hdc・si
nθ, usually Hdc-sinθ=5 [Oe] ~ 6 (
An inclination angle of 0 is selected so that the angle of inclination is 0. Also, the direction of this in-plane component Hdc is the starting point and direction of the rotating magnetic field Hr.
It is tilted to match the stop (St/Sp) direction (+x-axis direction). And this xy plane component Hd
c is the start/stop of the rotating magnetic field Hr (s t/S
p) It is a well-known magnetic field that has an effective effect on the operation and is called a holding field. Note that the magnitude of the bias magnetic field Hb acting perpendicularly to the chip CHI surface is Hz-cosθ. Now, since the above-mentioned holding field HdC always acts on the 11th surface of the chip CHI, the 29th
As illustrated in FIG. B, the rotating magnetic field Hr' acting on the chip CHI is eccentric. In the figure, Hr is a rotating magnetic field applied from the outside, and Hr' is a rotating magnetic field acting on the chip CHI. In this case, the rotating magnetic field Hr' acting on CHI is a combination of the rotating magnetic field Hr applied from the outside and the in-plane component Hda, and the center 0' of the rotating magnetic field Hr' is in the start/stop (St/Sp) direction. It moves in parallel in the +X-axis direction by an in-plane component Hdc. Therefore, as is clear from the results in the figure, even if the strength of the externally applied rotating magnetic field Hr is 1 Hrl, the strength lHr'l of the rotating magnetic field that effectively acts on the element CHI is the same as that of the rotating magnetic field Hr. Depends on the phase. That is, St/Sp
IHr'l in the direction is IHr I+IHd c I, and compared to 1Hrl, the holding field Hd
The strength of c is increased by IHd c l. On the contrary, S
IHr'l in the opposite direction to the t/S p direction is I
Hrl-lHdcl, 1Hdc compared to 1Hrl
It is weakened by l. (Peripheral Circuit FIG. 30) Finally, the peripheral circuit of the chip CHI will be explained with reference to FIG. 30. RF is a circuit for generating a rotating magnetic field Hr by passing currents with a phase difference of 90° through the X and Y coils of the chip CHI. SA is a sense amplifier that detects and amplifies a minute bubble detection signal from the magnetoresistive element of the chip CHI by synchronizing it with the timing of the rotating magnetic field. DR is MB
This is a drive circuit that sends current at a predetermined timing to each functional conductor of the replicates related to bubble generation, swap, and readout related to the insertion of the M device. The above circuit is synchronized by a timing generation circuit TG so as to operate in synchronization with the cycle and phase angle of the rotating magnetic field Hr. (Rotating magnetic field distribution characteristics Fig. 31) Fig. 31 shows the rotating magnetic field distribution characteristics of the magnetic circuit PFC described above. X with center as ○
The length in the axial direction is expressed as the rotating magnetic field strength H in the X-axis direction on the vertical axis.
When the rotating magnetic field strength Hx in the X-axis direction when x = O is shown, a rotating magnetic field distribution characteristic as shown by curve I was obtained. As is clear from the figure, a substantially uniform rotating magnetic field strength Hx is obtained within the range of -Xc to +XC between the opposing cores COR of the magnetic circuit PFC, and
Effective area of HI (minimum range to which rotating magnetic field should be applied) -
In the range of Xe to +Xe, a magnetic field strength uniformity of about 2% was obtained. Note that the curve (2) indicated by a broken line is the rotating magnetic field distribution characteristic due to the magnetic circuit of the conventional configuration. [Effects of the Invention] As explained above, according to the present invention, a magnetic bubble memory element mounted on a flexible wiring board is provided. A space that generates a leakage magnetic field by being disposed in the space of the rotating magnetic circuit of the picture frame-shaped core, and the entire core is sandwiched within a rotating magnetic field confinement case made of a highly conductive material, and its periphery is electrically connected. tJs, a highly uniform rotating magnetic field can be obtained with a small VI product, and the single-rotation magnetic field confinement case can be made smaller, resulting in lower power consumption.The magnetic bubble memory has a smaller and thinner overall shape. An extremely excellent effect can be obtained in that a device can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially cutaway perspective view showing the entire magnetic bubble memory device according to the present invention, FIG. 2A is a bottom view, FIG. 2B is a sectional view taken along line 2B-2B of FIG. Figure 3 is an exploded perspective view showing the stacked structure, Figure 4 is a diagram explaining the board FPC, and Figure 5 is an exploded perspective view showing the stacked structure.
The figure shows board assembly B with chip CHI mounted on the board FPC.
FIG. 6 is a plan view showing the chip CHI, FIG. 7 is a diagram explaining lead bonding of the board assembly BND, FIG. 8 is a diagram explaining the magnetic circuit PFC, and FIG. 9 is a diagram showing the magnetic circuit. A diagram explaining the manufacturing method of PFC, FIG. 10 is a diagram showing the inner case RFSb, and FIG. 11 is a diagram showing the outer case RF.
Figure 12 is an assembly diagram of case RFS, Figure 1 shows Sa.
3 is a sectional view of an assembly in which the board assembly BND and the magnetic circuit FPC are housed in the case RFS, FIG. 14 is a diagram explaining the configuration of the magnet body BIM, FIG. 15 is a diagram explaining the bias coil, Figure 16 is a cross-sectional view of the case RFS assembly incorporating a pair of magnets BIM and bias coil BIC, and Figure 17 is the outer shield case S H
The figure showing I a, Fig. 18 is the inner shield case 5HI
Figure 19 is an assembly diagram of the shield case SHI, and Figure 20 is an assembly diagram of the shield case SHI shown in Figure 16.
21 is a diagram showing the packaging case PKG; FIG. 22 is a diagram explaining the configuration of the terminal fixing plate TEF; FIG. 23 is a diagram showing the configuration of the contact pad; FIG. 24 is a cross-sectional view of the chip CHI,
Figure 25 shows the configuration of the magnetic bubble detector of chip CHI, and Figure 26 shows the magnetic bubble generator G of chip CHI.
A diagram showing the configuration of EN, FIG. 27 is a diagram showing the configuration of swap gate SWP of chip CHI, and FIG. 28 is a diagram showing the configuration of swap gate SWP of chip CH.
Figure 29 showing the configuration of the replicate gate REP of I.
Figure A shows the relationship between the bias magnetic field Hb and the holding magnetic field Hdc, Figure B shows the total rotating magnetic field Hr', Figure 30 shows the overall circuit of the magnetic bubble memory board, and Figure 31 shows the rotating magnetic field. It is a distribution characteristic diagram. CHI...Magnetic bubble memory chip (element). FPC...Flexible wiring board (substrate), BND/
... Board assembly, CO work... Drive coil (coil),
COR...Picture frame-shaped core (core). PFC...magnetic circuit, RFS...rotating magnetic field confinement case (case), RFSa...outer case, RFS
b...Inner case, BIM...Magnet for generating bias magnetic field (magnet), BIMa...Top magnet, BIM
b...lower magnet body, INM...inclined plate, MAG...
・Permanent magnet plate (magnetic plate), HOM...Magnetic shunt plate, INN
...Nonmagnetic gradient plate, BIC...Bias magnetic field generation coil (bias coil), SHI...External magnetic shield case (shield case), 5HIa...Outer shield case, 5HIb...Inner shield case , P
KG...Packaging case, TEF...Terminal fixing plate, GNP...Contact pad, 1...Element mounting part, 2.2a, 2b. 2G, 2d... bending portions, 3, 3a, 3b. 3c, 3d...External connection terminal connection section, 4, 4a. 4b---opening, 5, 5a, 5b, 5c...perforation,
6... Board protrusion, 7... Base film, 8...
・Adhesive, 9a... Wiring lead, 9b... External terminal, 9G... Connection terminal, 9d... Symbol, 9e...
・Index mark, 10...Cover film, 1
DESCRIPTION OF SYMBOLS 1...Tin plating layer, 12...Opening, 13...Solder plating layer, 14...Ponding pad, 15...
Gold bumps, 20a, 20b, 20c, 20d... Helix coil, 21a, 21b... Connection points. 22a...X coil, 22b...Y coil, 23.
...Magnetic core, 24...Tap, 25...Wide groove, 26...Small width groove, 30...Aperture part, 3
1...Bending part, 32...Notch part, 33...
Squeezed part, 34... bending part, 35... notch part,
36... Polyimide film, 37... Adhesive, 3
8... Coil winding, 40... Winding wire, 51... Flat part, 52... Bent part, 53... Concave part, 54...
- Notch portion, 55... Flat portion, 56... Bent portion, 57... Recessed portion, 58... Notch portion, 59... Recessed portion, 60... Resin plate, 61... Through hole, 62...
Non-through hole, 63 mark. 64...Opening, 65...Groove, 66...Corner. 70... Bare piece, 71... Nickel plating layer, 72...
・Gold plating layer.

Claims (1)

[Claims] A magnetic bubble memory element mounted on a flexible substrate is disposed in a space formed by a frame-shaped core coiled so that sets of opposing windings are parallel to each other, and the coil, core, and magnetic bubble memory element are mounted on a flexible substrate. A magnetic bubble memory characterized by having the entire element sandwiched within a case made of a highly conductive material.