JPS5812665B2 - magnetic bubble element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic bubble element, particularly a cylinder which is stably formed by applying a bias magnetic field perpendicular to the plate surface from the outside in a certain kind of magnetic thin plate (for example, orthoferrite or garnet film). The present invention relates to a magnetic bubble transfer circuit that transfers magnetic domains (magnetic bubbles).

Usually, as a magnetic bubble transfer circuit, a pattern of a soft ferromagnetic thin film such as permalloy is formed on the magnetic thin plate that forms magnetic bubbles, and a rotating magnetic field that rotates within this batten plane is applied externally. A system in which the soft ferromagnetic thin film pattern is magnetized by a rotating magnetic field is often used.

As a transfer circuit button of this method, T-Bar
Known battens such as patterns or chevron patterns are commonly used.

The magnetic bubble transfer circuit to which the present invention relates relates to the case of a chevron pattern.

FIG. 1 is a plan view of essential parts showing an example of a chevron pattern.

In the figure, each chevron pattern 1a has a ``h'' shape symmetrical to the Y axis, and is formed of a soft ferromagnetic thin film such as permalloy on a magnetic thin film. It is the basic constituent element.

FIG. 2 is a plan view of essential parts showing an example of a conventional magnetic bubble element, particularly a magnetic bubble transfer circuit.

In the figure, numeral 1 denotes a chevron pattern, and this chevron pattern 1 is constructed by stacking individual chevron patterns 1a in five stages with an interval width S in the Q direction in the same layer.

A plurality of these five-stage chevron patterns 1 are arranged in parallel with a predetermined interval g between adjacent patterns, thereby forming a five-stage chevron transfer circuit 2.

Moreover, 3 is a rotating magnetic field HR, and this rotating magnetic field 3 is applied so as to rotate in a counterclockwise direction so as to transfer the magnetic bubble 4 in the direction of arrow P.

Further, 5 is a bias magnetic field HB. In the magnetic bubble transfer circuit configured in this manner, the magnetic bubbles 4 on the chevron pattern 1 are sequentially transferred on the transfer circuit 2 as the rotating magnetic field 3 rotates.

However, in the magnetic bubble transfer circuit having the above configuration, when the magnetic field HB of the bias magnetic field 5 is increased, the magnetic baffle 4 during transfer is extremely easily eliminated.

It has drawbacks such as the magnetic bubble element malfunctioning.

That is, the extinction of the magnetic bubble 5 occurs when the magnetic bubble 4 crosses the gap g between the chevron battens 1 adjacent to each other in the transfer direction P, and the gap g in the transfer direction P
The larger the value, the easier the magnetic bubble 4 will disappear, and the upper limit value of the bias margin will be lowered.

Therefore, in order to solve this problem and obtain a transfer circuit with a wider bias margin width ΔHB, it is sufficient to reduce the gap y in the P direction.

However, the gap y between adjacent chevron battens 1 is
It cannot be made smaller than a certain value of 9 min determined by restrictions on the transfer circuit manufacturing technology.

In the current photolithography technology, the gmin is limited to about 1 μm.

Therefore, an object of the present invention has been made with attention to the above points, and is to provide a magnetic bubble element that makes it difficult for magnetic bubbles to disappear during transfer to obtain a transfer circuit with a wide bias margin width ΔHB. Our goal is to provide the following.

In order to achieve this purpose, the magnetic bubble element according to the present invention has chevron battens formed in the same layer adjacent to each other in the transfer direction. This is how it was done.

The magnetic bubble element according to the present invention will be described in detail below with reference to the drawings.

3a and 3b are principal part plan views showing an embodiment of a magnetic bubble memory element, particularly a magnetic bubble transfer circuit, according to the present invention, and the same symbols as in FIGS. 1 and 2 are the same elements, so that Explanation will be omitted.

In Figure a, the chevron battens 5a and 6b, which are the basic constituent elements of the transfer circuit, have different lengths of the arms extending on both sides of the "he" shape, and are asymmetrical with respect to the Y axis. It is formed.

In addition, the same figure b shows the chevron patterns 5a and 6b as P
A plurality of chevron patterns 6 are formed alternately and repeatedly in the direction and the Q direction, and a five-stage chevron transfer circuit 7 is constructed in the same layer.

In the magnetic bubble transfer circuit configured in this way, two chevron buttons 6a and 6b adjacent in the transfer direction P
As is clear from Figure b, the local gaps gloc formed by the gloc are shifted alternately left and right with respect to the direction Q perpendicular to the P direction.

As a result, the chevron patterns 6a and 6b mesh with each other like gears within the gap.

As a result, the effective gap geff when looking at the local gap gloc as a whole in the Q direction becomes smaller than gloc, and becomes geff~0 in the case of the same figure.

Therefore, since the gap between adjacent chevron battens 6 becomes magnetically small, this part can be used as a magnetic bubble 4.
The magnetic bubbles 4 can be easily crossed, and the disappearance of the magnetic bubbles 4 can be prevented.

4a and 4b are principal part plan views showing other embodiments of the magnetic bubble memory element, particularly the magnetic bubble transfer circuit, according to the present invention, and the same symbols as in FIGS. 1 and 2 are the same elements, so The explanation will be omitted.

In the same figure, the difference from FIGS. 3a and 3b is that the chevron patterns 8a and 8b, which are the basic structure of the transfer circuit, are
The chevron patterns 8a and 8 are formed in the shape of a
The lengths of the arms are different between the two arms, and they are each formed in a symmetrical shape with respect to the Y axis.

In addition, FIG. b shows that the Chevron patterns 8a and 8b are
A plurality of chevron patterns 8 are formed alternately in the direction and the Q direction, and a five-stage chevron transfer circuit 9 is constructed in the same layer.

In the magnetic bubble transfer circuit configured in this way,
Two chevron patterns 8a, 8 adjacent to each other in the transfer direction P
The local gap gloc formed by b is shifted left and right with respect to the direction Q perpendicular to the P direction, as shown in b of the same figure.

As a result, the chevron patterns 8a and 8b mesh with each other like gears at the gap portion.

In this case as well, the effective gap geff is smaller than gloc, and the same operation and effect as described above can be obtained.

In the above embodiment, a 5-stage chevron transfer circuit consisting of 5-stage chevron battens was explained.
The present invention is not limited to this, and even when applied to an n-stage chevron transfer circuit in which the number of chevron stages is n, the same effects as described above can be obtained.

Further, in the above embodiment, the case where the position of the gloc in the P direction is varied with respect to the Q direction is explained.
It goes without saying that the present invention is not limited to this, and that the same effects as described above can be obtained even if the present invention is applied to other cases in which geff is reduced by varying the position of gloc.

As explained above, according to the magnetic bubble element according to the present invention, the effective gap gef between adjacent chevron battens
f can be made small.

Therefore, the upper limit value of the bias margin, which is a magnetic bubble transfer characteristic, becomes high, and the margin width ΔHB can be widened, which has excellent effects.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an essential part showing an example of a conventional chevron pattern, FIG. 2 is a plan view of an essential part showing an example of a conventional magnetic bubble element, particularly a magnetic bubble transfer circuit, and FIGS. 3 a and b are in accordance with the present invention. FIGS. 4a and 4b are plan views of essential parts showing another embodiment of the magnetic bubble element, particularly a magnetic bubble transfer circuit, according to the present invention. It is a diagram. 1, 1a... Chevron slam, 2...
・Chevron transfer circuit, 3...Rotating magnetic field, 4.
...Magnetic bubble, 5...Bias magnetic field,
6, 6a, 6b...Chevron bang, 7...
...Transfer circuit, 8, 8a, 8b...Chevron baton, 9...Transfer circuit.

Claims (1)

[Claims] 1. In an n-stage chevron magnetic bubble transfer circuit in which n stages of chevron patterns are stacked in the same layer in a direction perpendicular to the transfer direction of magnetic bubbles, the spacing between adjacent chevron patterns in the transfer direction is vertical. A magnetic bubble element that differs in its characteristics in that the bangs interlock with each other at spaced positions. 2. The magnetic bubble element according to claim 1, wherein the chevron pattern is formed by alternately overlapping n stages of patterns each having a laterally asymmetrical shape. 3. The magnetic bubble element according to claim 1, wherein the chevron pattern is formed by alternately overlapping n stages of patterns each having a bilaterally symmetrical shape and having different arm lengths.