JPS6245631B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic bubble element using magnetic bubbles. More specifically, the present invention relates to a magnetic bubble element having a conductor pattern that controls switching of a magnetic bubble transfer path.

As a method to reduce the information access time of the magnetic bubble element, the structure of the magnetic bubble element is
It is well known to have a minor loop configuration. This major/minor loop configuration consists of a large number of loop-shaped magnetic bubble transfer paths (minor loops) for storing information, and a common magnetic bubble transfer path (major loop or major line, hereinafter referred to as major line) for reading or writing information. This memory structure has a structure in which the average access time of information in the minor loop is shortened and has a high tolerance to defects caused by the magnetic bubble element manufacturing process.

One of the essential functional elements in a bubble element having a major/minor loop configuration is a function of transferring information of a minor loop to a major line with good controllability or a function of transferring information on a major line to a minor loop with good controllability. The elements that perform these functions are usually called transfer gates.
The transfer gate function is normally controlled by a conductor pattern for controlling the transfer gate operation and a control current pulse connected thereto.

The conventional conductor pattern for transfer gate control was described in September 1973 by Smith et al.
Smithet al, IEEE Trans.on Mogn.MAG−9
(No. 3), 285 (1973)) was common. It has generally been said that the size of such a meandering conductor pattern is approximately the diameter of a magnetic bubble.

When small magnetic bubbles are used to increase the information storage capacity of magnetic bubble elements, the transfer pattern of the magnetic bubbles must be made smaller accordingly. Along with this, the dimensions of the conductor pattern for controlling the transfer gate operation must also be made thinner and smaller. However, although conductor patterns are usually manufactured using optical lithography technology, it is extremely difficult to form patterns of 2 μm or less using such optical lithography technology.

An object of the present invention is to provide a magnetic bubble element having a conductor pattern for controlling transfer gate operation, which eliminates such drawbacks.

Next, the present invention will be explained in detail using the drawings while comparing it with a conventional example. As shown in FIG. 1, the present invention comprises a bubble magnetic domain material 1 capable of holding magnetic bubbles, a first magnetic bubble transfer path 2 provided on the bubble magnetic domain material, and a second magnetic bubble transfer path provided in the vicinity thereof. conductor pattern 4 for controlling the transfer gate operation provided between the first transfer path 2 and the second transfer path 3;
It is a magnetic bubble element composed of.

Next, we will discuss the conductor pattern for controlling the transfer gate operation in the conventional magnetic bubble element in the second section.
This will be explained in more detail using figures. The conventional control conductor pattern 4 is generally formed of a meandering conductor having a width approximately equal to the diameter of a magnetic bubble, as shown in the figure. The specific shape is often more complicated than that shown in FIG. To control the gate operation using this conductor pattern, the gate operation control current 60
I'll do it through. At this time, a bias magnetic field component is generated in the direction 5 of the slit-formed part 41 of the pattern in the direction of attracting magnetic bubbles, and in the 5' part of the other slit-shaped part 42, the bias magnetic field component is generated in the direction of repelling the magnetic bubble. A bias magnetic field component is generated. By attracting or repelling the magnetic bubbles using this generated magnetic field, the transfer direction of the magnetic bubbles can be controlled.

If we make the magnetic bubble smaller and increase the storage density in order to increase the information storage capacity, the transfer path pattern of the magnetic bubble must also be made smaller in proportion to that, and the conductor pattern for gate operation control must also be made thinner accordingly. As mentioned above, it is necessary to shorten the repetition period, but the conductor width cannot be made very thin. This is because when the conductor is made thinner, the resistance value increases, power consumption increases, and at the same time, the conductor becomes vulnerable to disconnection due to overcurrent. Moreover, for example, in the case of a magnetic bubble device with a diameter of 1 μm, this transfer gate period is
It is approximately 8 μm.

When a meandering pattern is created with a period of 8 μm, the pattern width is 2.
μm slit part is 2μm or pattern width is 3μm
A configuration in which the size of the slit portion is 1 μm is conceivable, but with the current optical exposure technology, it is quite difficult to create a pattern of 2 μm or less.

FIG. 3 is a diagram of a first embodiment illustrating the present invention. The present invention is based on the basic principle that the current distribution in a conductor is such that the total electrical resistance is minimized. The conductor pattern 4 shown in FIG. 3 is provided with a slit-like portion 43 so as to have a comb shape. When a current is passed through this conductor, the current flow 61
The current distribution in the vicinity of the portion 5 of the slit 43, which attempts to lower the total resistance by spreading and distributing over the wide conductor portion 70 sandwiched between the slit portions 43, is exactly as shown in Fig. 2. It will be the same. The magnetic field distribution generated along with this is also similar to that shown in FIG.

Therefore, using this magnetic field distribution, switching control of the magnetic bubble transfer path becomes possible.

For a magnetic bubble element using magnetic bubbles with a diameter of 1 .mu.m, the gate operation control conductor pattern according to this embodiment only needs to be provided with slit-like portions at a period of about 8 .mu.m as described above. Therefore, it is possible to form a shape with sufficient margin in terms of dimensional accuracy. For example, if the slit portion 43 is provided with a width of 2 μm, the width of the wide conductor portion 70 is 6 μm. This is a size that can be sufficiently produced using current optical exposure technology.

FIG. 4 shows a gate operation control conductor pattern according to a second embodiment of the present invention. This conductor pattern is basically the same as the conductor pattern according to the first embodiment shown in FIG. However, the difference is that the wide conductor portion 70 is provided with a cutout portion 44 in the pattern in the opposite direction to the notch of the slit portion 43. Due to the presence of the pattern missing portion 44, when a current is passed through the conductor pattern 4, more current is distributed in the wide pattern portion 70. Therefore, the magnetic field generation in the portion 5 of the slit portion 44 becomes more efficient.

As described above, if the conductor pattern for gate operation control according to the present invention is used, even in a high-density magnetic bubble element using minute magnetic bubbles, the conductor pattern has a large pattern size and is easy to manufacture. A magnetic bubble element will be realized.

Further, in the above explanation, the transfer gate operation has been mainly described as the gate operation of the magnetic bubble, but the conductor pattern according to the present invention can also be used as a control conductor pattern for the replicator operation or the swap gate operation. Needless to say.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the configuration of the present invention, FIG. 2 is a diagram showing a conventional example of a conductor pattern for controlling transfer gate operation, and FIG. 3 is a diagram showing the transfer gate operation according to the first embodiment of the present invention. FIG. 4 is a diagram showing a conductor pattern for controlling a transfer gate operation according to a second embodiment of the present invention. 1 is a bubble magnetic domain material, 2 is a first magnetic bubble transfer path, 3 is a second magnetic bubble transfer path, 4 is a conductor pattern for controlling transfer gate operation, 41, 4
2 and 43 are slit-shaped portions of the conductor, 44 are pattern missing portions, 5 and 5' are magnetic field generation portions, 60 and 6
1 and 62 represent the current distribution in the conductor, and 70 represents the wide portion of the conductor pattern.

Claims (1)

[Claims] 1. On a bubble magnetic domain material capable of holding magnetic bubbles, a first magnetic bubble transfer path capable of transferring magnetic bubbles, a second magnetic bubble transfer path provided in the vicinity thereof, and a magnetic bubble transfer path The transfer gate operation is performed in a magnetic bubble element comprising at least a conductor pattern for controlling transfer gate operation for switching from the transfer path to the second transfer path or from the second transfer path to the first transfer path. A magnetic bubble element characterized in that a control conductor pattern has a comb-like shape.