JPS624955Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Technical Field of the Invention The present invention relates to a magnetic bubble memory device as a storage medium with cylindrical magnetic domain control.

(b) Background of the technology For example, a memory device that is assembled with a bubble memory chip made of a garnet single-crystal thin plate, etc., and a coil, magnet, etc. that applies a bias magnetic field for holding generated bubbles to the memory chip, a rotating magnetic field for bubble transfer, etc. It is prized as a small, lightweight, non-volatile memory medium.

The present invention relates to the assembly of a flat device including a flat coil, and particularly to improving the airtightness of a memory chip package sealing structure.

(c) Problems with the Prior Art FIG. 1 is a perspective view showing the base structure of a flat package body consisting of a flat coil and a reflecting plate that generate a rotating magnetic field for bubble transfer.

In the figure, 1 is a memory chip, 2 is a reflective plate made of a non-magnetic and conductive metal thin plate, such as a copper plate (a thin plate of about 0.3 mm, although it varies depending on the frequency of driving the memory chip), and 3 is parallel to the upper part of the reflective plate 2. This is a planar flat coil arranged as shown in the figure, which consists of stacked X and Y planar coils Cx and Cy as shown in the figure. The flat coil 3 and the reflection plate 2 apply a rotating magnetic field for bubble transfer from above and below the memory chip 1.

Further, numeral 4 in the figure is a ferromagnetic plate made of a thin ferrite plate, a thin permalloy plate, etc., and is commonly called a homogenizer. Reference numeral 5 denotes a magnet for applying a bias magnetic field to keep the bubbles inside the memory chip 1 steady.

Furthermore, regarding the construction method and operating functions of the flat coil and the reflector 2,
061652, ``Magnetic Bubble Driving Coil''.

By the way, conventional memory devices of this type have focused on miniaturization, especially thinness, for convenient portability, and no consideration has been given to airtight sealing of the chip inside the package.

(d) Purpose of the invention The purpose of the invention is to solve the above problems.

That is, the objective is to improve the hermetic sealing function of the memory chip and to realize a magnetic bubble memory device which is thinner and has better assembly efficiency.

(e) Structure of the invention The above object is to provide a magnetic bubble memory chip;
An insulating substrate having a penetrating window for accommodating the memory chip, a flat coil formed by laminating X and Y plane coils arranged in parallel to generate a rotating magnetic field for bubble transfer, and a reflection plate made of a non-magnetic and conductive metal. At least the circuit board is provided with a conductor circuit connected to the control circuit in the memory chip, and a large number of external terminals for external extraction are provided at the end of the circuit board, and a circuit board is formed on the back surface of the board. The reflective plate to which the memory chip is fixed is positioned and bonded to the memory chip within the window for connection to the conductor circuit, and a sealing plate that covers the window is bonded to the surface of the substrate. This is achieved by a magnetic bubble memory device characterized in that the flat coil is placed thereon.

(f) Example of the invention Below, Figures 2 and 3 are examples of the invention.
The present invention will be explained in detail with reference to the figures.

FIG. 2 is an exploded perspective view showing an embodiment of the memory device configuration, and FIG. 3 is an assembled perspective view of FIG.

In Fig. 2, a memory chip 1, a reflection plate 2 made of a thin copper plate, and an X and Y planar coil Cx are shown.
Portions with the same reference numbers as in the previous figure, such as the flat coil 3 on which Cy is laminated, have the same functions.

The reflector plate 2 is arranged parallel to the flat coil 3, and an eddy current is generated by the alternating magnetic field applied to the coil, and the eddy current effect acts on the memory chip 1 between them as if an image coil were present. generates a rotating magnetic field for bubble transfer.

In the perspective view of FIG. 2, 6 is an insulator such as a ceramic substrate, 7 is an external terminal provided at both ends of the substrate 6, 8 is a rectangular window opened approximately in the center of the substrate 6, and 9 is a rectangular window of the substrate 6. This is a sealing plate that covers and seals the window 8 from the front side.

Note that the ceramic substrate 6 constitutes a circuit board on which a large number of conductor circuits (not shown) are formed, and the conductor circuits are connected to the bubble generator in the memory chip 1,
In order to connect a control circuit such as a bubble switch or a bubble detector to the external terminal 7, it is led out from the periphery of the window 8 to the outer periphery of the board.

The memory chip 1 is fixed approximately in the center of the reflector plate 2 by adhesive or the like, and the window 8
The reflection plate 2 is fitted onto the back surface of the substrate 6 and bonded to the back surface of the substrate 6.

Then, the substrate 6 and the reflecting plate 2 are thoroughly bonded to each other on the back surface of the substrate by, for example, a glass bonding technique to achieve an airtight connection on one side. On the other hand, on the front surface side of the substrate 6, after bonding the ends of the conductive circuits exposed around the window 8 and the terminal pattern of the bubble memory chip 1 with wires 12, the window 8 is closed.
A sealing plate 9 is attached to seal the area to provide airtightness.

In the figure, 10 is a recess formed on the surface side of the substrate 6. After a sealing plate 9 is attached to the recess 10, a flat coil 3 and a thin ferrite plate 4 are sequentially laminated from above, and the laminate is assembled. The device assembly is completed by fitting it into a shield case 11 made of a ferromagnetic material with both ends open.

Note that the board 6 on the left side as viewed from the second paper has a reflector 2 bonded to the back surface of the board 6 so that the memory chip 1 mounted on the reflector 2 is located within the window 8, and wire bonding. Board 6
The sealing plate 9 is connected to the memory chip 1.
The substrate 6 on the right side shows the state before the reflection plate 2, the sealing plate 9, etc. are attached.

FIG. 3 is a perspective view of the assembled device.

By assembling in this manner, a thin device with good airtightness and excellent stability can be realized.

(g) Effects of the invention According to the bubble memory device of the invention described in detail above, the memory chip is hermetically sealed in a flat package body comprising a flat coil and a reflector, and the memory chip is not exposed to the outside. Because the structure utilizes a board from which terminals are drawn out and assembles components such as flat coils and reflectors on the front and back surfaces of the board, there is no need for separate parts such as spacers to maintain the distance between the flat coil and reflector, making assembly easy. Its practical effects are remarkable, such as improved performance and further thinning.

[Brief explanation of the drawing]

FIG. 1 is a perspective view illustrating the basic configuration of a conventional memory device including a flat coil and a reflector;
FIGS. 2 and 3 are an exploded perspective view and a perspective view of a completed assembly, respectively, showing an assembled configuration of a memory device according to an embodiment of the present invention. In the figure, 1 is a memory chip, 2 is a reflector, 3 is a flat coil, 4 is a ferrite plate, 6 is a ceramic substrate or substrate, 8 is a window, 9 is a sealing plate, and 11 is a shield case.

Claims (1)

[Claims for Utility Model Registration] A magnetic bubble memory chip, an insulating substrate having a through window for accommodating the memory chip, and a flat coil formed by laminating X and Y plane coils arranged in parallel to generate a rotating magnetic field for bubble transfer. The substrate includes at least a reflective plate made of a non-magnetic and conductive metal, a conductive circuit connected to a control circuit in the memory chip is formed on the substrate, and a large number of external terminals for external extraction are formed on the end of the conductive circuit. The reflection plate to which the memory chip is fixed is bonded to the back surface of the substrate by positioning the memory chip within the window for connection to the conductor circuit, and the reflection plate is bonded to the back surface of the substrate. A magnetic bubble memory device characterized in that a sealing plate covering the window is bonded to the flat coil and the flat coil is mounted on the flat coil.