JPS6342355B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic bubble memory device used in a storage device such as an electronic computing device, and more particularly to a magnetic bubble transfer controller for a memory element thereof.

Conventionally, in a magnetic bubble memory device, its magnetic bubble transfer controller, such as a swap gate,
For transfer gates, etc., a combination of a Hahoo disk-type soft magnetic thin film pattern and a hairpin conductor has been used. However, as the density of memory elements increases and each pattern becomes finer, bubbles tend to collapse due to the difference in level at the intersection of the soft magnetic pattern and the conductor pattern and stress on the conductor, resulting in deterioration of the transfer margin.

[Conventional technology]

For this reason, recently, a pickax type soft magnetic thin film pattern is used which can increase the transfer margin. FIG. 5 is a diagram showing a conventional swap gate. In the figure, 1 indicates a pickax type soft magnetic thin film pattern, 2 indicates a hairpin conductor, 3 indicates a medium transfer path, 4 indicates a minor loop, and arrow 5 indicates the direction of bubble travel. By applying a pulse current to the hairpin conductor 2 at appropriate times, bubbles can be transferred from the major transfer path 3 to the minor loop 4 or vice versa.

[Problem that the invention seeks to solve]

In a magnetic bubble controller such as a swap gate or a transfer gate that combines a Pickax pattern and a hairpin conductor as described above, the deterioration of the transfer margin at the intersection of the Pickax pattern and the conductor pattern is shown in Figure 6. It will be improved as follows. In the same figure, curve A,
Curve A' is the case when a pickax type pattern is used, and curves B and B' are the case when a half disk type pattern is used.
However, since the driving force of the head of the Pickax type pattern is too strong, there is a problem in that the minimum value of the swap current is larger than that of the half disk type, as shown in FIG. In the same figure, curves C and C' show the case when a pickax pattern is used, and curves D and D' show the case when a half disk type is used.

[Means for solving problems]

The present invention provides a magnetic bubble transfer controller that solves the above-mentioned problems. In a magnetic bubble transfer controller in which magnetic thin film patterns are laminated, the length from the base of the foot to the tip of the foot is equal to or shorter than the pattern width of the head, and Both sides of the hairpin conductor are arranged inside the center of the width of the parallel pattern of the hairpin conductor, and the height from the base of the foot to the top of the head is 1/3 or less of the width of the pattern of the head. This is done by a magnetic bubble transfer controller characterized by the following.

[Effect]

The above magnetic bubble transfer controller can reduce the gate current value within a range that does not cause margin deterioration at the intersection with the conductor pattern by forming the Pikachus type soft magnetic thin film pattern into the above shape.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows an embodiment of the present invention. This figure shows the main parts of the swap gate.
11 indicates a Pickax-type pattern of a soft magnetic thin film, 11 indicates a hairpin conductor, a and a' indicate both sides of the foot of the Pickax-type pattern, and b and b' indicate the center lines of the parallel patterns of the hairpin conductor, respectively. .

In this example, the height from the base of the foot to the top of the head of the Pikachus type pattern 10 is C, the length l from the base of the foot to the tip of the foot, and the pattern width of the head is W. Then, l≦W and C<W/3, and both sides a, a' of the foot are arranged inside each center line b, b' of the parallel pattern of the hairpin conductor.

Figure 2 shows the relationship between the C dimension and the minimum swap current when W = 13 μm. In the figure, the horizontal axis represents the C dimension, the vertical axis represents the minimum swap current, and the curve a Therefore, if l>W, the curve b
The curve C shows the case l=W, and the curve C shows the case l<W. From the figure, the C dimension is l=W
Or, it can be seen that when l<W, W/3 or less is good.

The characteristics of the swap gate of this embodiment constructed as described above are as shown in FIGS. 3 and 4. FIG. 3 is a diagram showing the swap current margin in comparison with the conventional example. In the figure, the horizontal axis represents the swap current, and the vertical axis represents the bias margin. The characteristics of the conventional example are shown by curves B and B', respectively.
Fig. 4 is a diagram comparing the transfer margin at the conductor intersection with a conventional example. In the figure, the horizontal axis represents the driving magnetic field, the vertical axis represents the bias margin, and curves C and C' are shown. The characteristics of this embodiment and the characteristics of the conventional example are shown by curves D and D', respectively.

The swap current margin of this embodiment is expanded toward the low current side as shown in FIG. 3, and the margin on the low current bias side is also improved as a result of consideration of the arrangement of the pickup feet. Further, as shown in FIG. 4, the margin at the conductor crossing portion is as good as that of the conventional type.

〔Effect of the invention〕

As described above, according to the present invention, by arranging the shape of the pickaxe pattern and the foot portions as described above, the current margin can be expanded without deteriorating the transfer margin at the conductor intersection.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a main part showing an embodiment of the magnetic bubble transfer controller of the present invention, and FIG. 2 shows the ratio of the head height dimension to the head pattern width of the Pickax type pattern in the swap gate and the minimum swap current. 3 is a diagram showing the current margin of the swap gate according to the embodiment of the present invention in comparison with the conventional example, and FIG. 4 is a diagram showing the transfer margin of the swap gate according to the embodiment of the present invention in comparison with the conventional example. Figure 5 is a plan view of a gate using a conventional Pickax-type pattern, and Figure 6 is a transfer margin of a gate using a conventional Pickax-type pattern and a gate using a half-disk pattern. FIG. 7 is a diagram showing the current margin of a swap gate using a conventional pickax type pattern and a swap gate using a half disk type pattern. In the figure, numeral 10 indicates a pickaxe type pattern, and numeral 11 indicates a hairpin conductor.

Claims (1)

[Claims] 1. In a magnetic bubble transfer controller in which a Pikachus-shaped soft magnetic thin film pattern is laminated via an insulating layer on a hairpin conductor for controlling bubble transfer by applying a pulse current, the Pikachus-shaped pattern is formed at the base of the foot. The length from to the tip of the foot is the same as or shorter than the pattern width of the head, and both sides of the foot are located inside the center of the width of the parallel pattern of the hairpin conductor, and A magnetic bubble transfer controller characterized in that the height from the base of the foot to the top of the head is 1/3 or less of the pattern width of the head.