JPS6161478B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a magnetic bubble memory device used as a storage device for an electronic computing device or its terminal.

(2) Background of the technology Magnetic bubble utilization devices that use magnetic bubbles to store information, perform logical operations, etc. are nonvolatile, have high storage density, low power consumption, and are solid-state devices that do not contain any mechanical elements. Because it is an element, it has various characteristics such as extremely high reliability, and is therefore expected to have a promising future as a large-capacity memory. This magnetic bubble memory device takes advantage of the fact that magnetic bubbles can be moved freely within a magnetic thin film with uniaxial anisotropy by a magnetic field. An element 1 having a bubble transfer path formed by an injection method, two orthogonal coils 2 and 3 that generate a rotating magnetic field for driving the bubbles along the transfer path, and for stably holding the bubbles. It is composed of magnets 4 and 5 for generating a bias magnetic field, a shield case 6, and the like.

(3) Prior art and problems In such magnetic bubble memory devices, if the bubble transfer path is created using a permalloy pattern, there is a limit to the dimensional accuracy of photolithography, and patterns created using ion implantation can be made smaller. Storage density can be increased. However, when the transfer path has a major-minor configuration, the operating margin of function gates such as transfer and replication is small when using the ion implantation method.
Therefore, a bubble device that is a combination of an ion-implanted bubble device and a permalloy device is considered, but there is no known conventional technology regarding the transfer and gate operation of bubbles between a pattern formed by ion implantation and a permalloy pattern. Therefore, the development of such technology is required.

(4) Object of the Invention In view of the above-mentioned conventional requirements, the object of the present invention is to provide a magnetic bubble memory device having a transfer pattern by ion implantation, a gate having a function of transmitting and receiving bubbles between permalloy patterns, and a replication operation. The purpose is to provide the following.

(5) Structure of the Invention According to the present invention, the cusp portion of the ion implantation transfer pattern forming a minor loop for storing information and the permalloy transfer pattern of the major line are connected with a U-shaped conductor pattern to form a non-conductor. A destructive readout gate is configured, and the gate is configured to convert the magnetic bubbles on the ion implantation transfer pattern into the permalloy transfer pattern by applying a bubble extension pulse and a bubble cutting pulse to the conductor pattern within one period of the rotational driving magnetic field. By providing a magnetic bubble memory device, the magnetic bubble memory device is characterized in that it has a gate function to divide one divided bubble onto the ion implantation transfer pattern and transfer the other divided bubble onto the major line. It will be achieved.

(6) Examples of the invention Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a diagram for explaining the magnetic bubble memory device according to the present invention, in which a shows a top view of the gate and b shows a cross-sectional view thereof.

In the figure, 7 is a pick-up permalloy pattern, 8, 8' is a bar-shaped permalloy pattern, 9,
9' is a half disk permalloy pattern, 10
is a minor loop, 11 is a conductor pattern,
12 is a magnetic bubble crystal, 13 is an ion implantation region,
14 and 15 indicate spacers, respectively.

In this embodiment, as shown in the figure, a minor loop 10 in a non-ion implanted region is formed in a magnetic bubble crystal 12 by an ion implantation method, and a spacer 1 is formed on the minor loop 10 in a non-ion implanted region.
A U-shaped conductor pattern 11 is formed through the conductor pattern 4, and a measure line 16 consisting of the permalloy patterns 7, 8, 8', 9, 9' is further formed through the spacer 15. Permalloy pattern 7 is minor loop 1
The conductor pattern 11 faces the cusp 0 and is arranged on a line connecting the two.

Next, the replicate operation of this embodiment configured as described above will be explained using the operation explanatory diagram of FIG. 3 and the operating current waveform diagram of FIG. 4.

First, as shown in figure a, when the driving magnetic field H _R turns in the direction of the arrow at time t ₀ , the bubble 17 of the minor loop 10 reaches the cusp C. Next, as shown in Figure b, at time _t1 , an expansion pulse Ist is applied to the conductor pattern 11 in the direction in which the bubble expands, causing the bubble 17 to expand.
Next, as shown in Fig. C, the driving magnetic field H _R rotates, and when the elongation pulse Ist is cut off at time _t2 , the bubble 17 contracts and is attracted to the head of the pickax permalloy pattern 7. When the stretching pulse Ist is turned off and the cutting pulse _Ic1 for bubble cutting is applied at the same time as shown in Fig. 4, the bubble is divided into two as shown in Fig. d. After that, a current Ic 2 is applied to hold the two bubbles 17' and 17'' on both sides of the conductor pattern 11 until the rotating magnetic field is split into two and the bubbles reach a phase suitable for returning to the major line and minor loop, _respectively . The current continues to flow in the same direction as Ic ₁ and at a lower value. Meanwhile, two bubbles 17' and 17'' extend between the pickax permalloy pattern 7 and the minor loop 10, as shown in figures e and f. Then the time
At t ₃ the current Ic ₂ is cut off. Then, as shown in figure g, one hypotenuse part m ₁ of the cusp C part of the minor loop 10
is the magnetic pole that repels the bubble, and the other oblique side m ₂ is the magnetic pole that attracts the bubble.
is magnetized by the attracting magnetic pole, and the head M2 on the right side is magnetized by the repelling magnetic pole, so the two bubbles 17' and 17'' are magnetized immediately after the current Ic ₂ is cut off. , a bubble 17'' is attracted to the oblique side _m2 of the minor loop 10, respectively. When the driving magnetic field further rotates, the bubbles 17' and 17'' move to the major line 16 as shown in figure h.
is propagated through the minor loop 10, and the replication operation is completed.

Next, the operation of the swap gate of the embodiment will be explained using the operation explanatory diagram of FIG. 5 and the operating current waveform diagram of FIG. 6.

First, when the driving magnetic field H _R is directed in the direction of the arrow at time t ₀ as shown in FIG.
Each of the 6 picks reach the permalloy pattern 7.

Next, as shown in figure b, at time t ₁ , an expansion pulse Ist is applied to the conductor pattern 11 in the direction in which the bubbles expand on the outside to expand the bubbles 17' and 17''.Then, the driving magnetic field rotates, and e As shown in the figure, when the extension pulse Ist is cut off at time _t2 , the bubbles 17' and 17'' contract, and the heads of the pick up permalloy pattern 7 of the major line are affected by the same action as explained in Fig. 3g above. and is attracted to the slope of the cusp of minor loop 10. When the driving magnetic field further rotates, bubbles 17', 1 as shown in figure d
7″ is major line 16 and minor loop 10
is propagated and the swap operation is completed. In other words, bubble 1 that is in minor loop 10 in diagram a
7' to major line 16, major line 1
The bubbles 17'' that were in the loop 6 are mutually exchanged into the minor loop 10.

As described above, according to the present invention, it is possible to create a composite bubble memory in which the minor loop part is made up of purely ion-implanted device parts and the major line part is made up of permalloy patterns. The gate function can be performed smoothly, and bubbles can be propagated from the ion implantation part to the permalloy part or vice versa without requiring a special loop or gate.

FIG. 7 is a diagram showing another embodiment of the gate in the magnetic bubble memory device of the present invention. In this figure, the same parts as in FIG. 2 are designated by the same reference numerals. This embodiment differs from the previous embodiment shown in FIG. 2 in that the conductor pattern 11 is rotated by 180 degrees and its operation and effects are exactly the same as those of the previous embodiment.

8 and 9 are views showing one example of the magnetic bubble memory device according to the present invention, FIG. 8 is an overall view, and FIG. 9 is an enlarged view of part A in FIG. 8. be. In both figures, there is one major line 16 made of permalloy, and one minor loop 1.
0 has three loops connected in a chevron shape and is formed by an ion implantation pattern. Information is then written from the generator 18 to the minor loop 10 by the swap function of the replicator/swap gate, and if necessary, the gate can be operated with the replicate function to send the information to the detector 19 and read it out.

(7) Effects of the Invention As described above in detail, the magnetic bubble memory device according to the present invention has an ion implantation bubble device that can be highly densified and operates with a relatively low driving magnetic field in the minor loop part, and has a replication operation. When applying a simple permalloy bubble device to a major line part where the pattern shape can be enlarged by taking advantage of each feature, the operation at the junction between the ion implantation part and the permalloy part, which is a problem, is made smooth and simple, and the overall characteristics are improved. It is a great advantage that a bubble memory device with good quality can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the conventional bubble memory device, FIG. 2 is a diagram for explaining the magnetic bubble memory device according to the present invention, and FIG. 3 is a diagram for explaining the gate replication operation in the magnetic bubble memory device according to the present invention. Diagram for explaining, No. 4
5 is a diagram for explaining the gate swap operation in the magnetic bubble memory device according to the present invention. FIG. 6 is a diagram of the operating current waveform. FIG. 7 is a diagram for explaining the operation current waveform of the magnetic bubble memory device according to the present invention. Figures 8 and 9 illustrating other embodiments of gates in memory devices are diagrams illustrating an example of a magnetic bubble memory device according to the present invention. In the drawing, 10 is a minor loop, 11 is a conductor pattern, 12 is a bubble crystal, 13 is an ion implantation region, 14 and 15 are spacers, 16 is a major line, and 17, 17', and 17'' are bubbles, respectively.

Claims (1)

[Claims] 1 A non-destructive readout gate is constructed by connecting the cusp portion of the ion implantation transfer pattern forming a minor loop for storing information and the major line permalloy transfer pattern with a U-shaped conductor pattern, and the gate is connected to one part of the rotational driving magnetic field. By applying a bubble extension pulse and a bubble cutting pulse to the conductor pattern within a cycle, the magnetic bubbles on the ion implantation transfer pattern are divided on the permalloy transfer pattern, and one of the divided bubbles is re-injected into the ion implantation pattern. A magnetic bubble memory device characterized by having a gate function for returning to the transfer pattern and transferring the other divided bubble onto the major line.