JPS5956283A - Bubble generator of contiguous disc bubble element - Google Patents

Abstract

PURPOSE:To improve the bubble generation characteristic, by changing the distance between the center of the thickness of a conductor layer and the surface of a bubble holding layer on the bubble transfer path side and the opposite side of boundaries near a bubble transfer path to allow a magnetic field due to a conductor current to exist locally practically. CONSTITUTION:Though shapes of a bubble transfer path and a conductor pattern 13 are the same as conventional those, spacing between the conductor layer and the bubble holding layer is changed on an inside 31 and an outside 32 near the bubble transfer path 12. The position for changing the spacing is about 2-3- fold length 33 of the bubble diameter distant from the end of the bubble transfer path 12. Since bubbles exist stably near the transfer path within this length 33 by the effect of the distortion generated by ion implantation, the magnetic field due to the conductor current is allowed to exist locally near the transfer path end also, and thus, bubble are generated more efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bubble generator for a continuous disk bubble device.

Conventionally, a method has been adopted for bubble devices in which a soft conductor pattern is provided on a bubble retaining layer with a gap so that bubbles are transported by ++g by in-plane magnetic field rotation.

However, this method is undesirable in terms of the gaps in the pattern, a reduction in bubble density, an obstacle to high-speed transfer of bubbles, and limitations on pattern fineness. In response, US Pat. No. 28,329 proposed an element that transfers bubbles using a pattern of gaps, and its development has been rapidly progressing in recent years.

On the other hand, the pattern is formed by ion implantation. Since the transfer pattern of that element had a shape of a series of circles, it became known as the 21st Intense Disc (21; I got caught and got 1 hit.

As a bubble generator for a CI) element, one in which a conductor pattern for bubbles is provided directly or via a space on a bubble retaining layer is commonly used. This conductor pattern is used to generate bubbles, the method of generating bubbles, and the deception of the conventional pattern bubble zero.
When a bubble occurs, the magnetic field from the magnetization of the permalloy pattern is used to stabilize the 74 (bubble generator), whereas in the case of a CD element, the magnetic field from the magnetization of the ion-implanted region is used. Basically, the magnetization of the bubble retention layer is reversed using a local magnetic field generated by an electric current. C1)
The element is characterized by a larger capacity than conventional elements. Therefore, the bubble generator for the CD element is required to have high bubble generation efficiency, that is, low power consumption, and to have as few malfunctions as possible.

FIG. 1 is a schematic plan view of an example of a conventional CD element bubble generator. The bubble 11 is generated by the current (... field) of the conductor pattern 13 at the end of the bubble transfer path 12.
The figure is a schematic cross-sectional view taken along a line 14 that cuts through the conductor pattern. The conductor layer 13 of the bubble generator is provided on the bubble retaining layer 21 with a spacer 22 interposed therebetween. The current required for bubble generation has a lower limit determined by the bubble material and ion implantation conditions, given the conductor pattern shape, the spacing 23 between the conductor layer 13 and the bubble retaining layer 21, etc. Furthermore, if too much current is passed, malfunctions such as generation of unnecessary bubbles are likely to occur if the current magnetic field is not sufficiently localized.

That is, there is an upper limit value for the current. For example, a hairpin-shaped conductor pattern as shown in FIG. 1 is usually used as the conductor pattern, but unnecessary bubbles often occur in the narrow portion 15 of the conductor pattern. Therefore, it is necessary to set the current to an appropriate value. ．． Due to the simplification of i, the conductor layer of the generator is made in the same layer as the conductor layers of other functional parts such as gates and senses, so the generator cannot be operated in an operating current region with somewhat poor characteristics. I have to let it happen. Therefore, malfunctions are likely to occur in commonly known strains due to changes in the operating range due to temperature changes. For example, there have been problems in that at low temperatures, the current required for bubble generation increases per hour, and at high temperatures, unnecessary bubbles are generated in large numbers.

The purpose of the present invention is to solve the problem of the increase in the bubble generation current of the bubble generator and the malfunction of unnecessary bubble generation when the current value is large, and to solve the problem that the magnetic field generated by the generator conductor is It is an object of the present invention to provide a bubble generator with improved characteristics by substantially localizing the bubbles. In a bubble generator for a CD element having a 2H8 layer for bubble generation thereon, the distance between the center of the film thickness of the conductor layer and the surface of the bubble retaining layer is set at 17 with the vicinity of the bubble transfer path as the boundary. A CDi element bubble generator is obtained, which is characterized in that it changes between the bubble transfer path side and the opposite side.

Incidentally, among conventional bubble generators using conductor patterns, the IE Transactions on Magnetics (II Bow ED Tralls).

+'vlagn, ) if> fvla g-9 (1973), No. 489u, there is a known structure in which conductor patterns are formed by providing groups in the bubble retaining layer.

It is assumed that this bubble generator has a step in the conductor layer, but the distance between the center of the thickness of the conductor layer and the surface of the bubble retaining layer is one foot, and the bubble generator of the present invention is structurally different. They are different. Therefore, there is no effect of suppressing malfunctions or reducing the number of malfunctions.

Further, as in the present invention, a photomask for manufacturing a magnetic bubble element that partially changes the distance between the conductor layer and the bubble holding layer in the vicinity of the generator is, for example, a through-hole type made of permalloy, rRfIJ Since it can be shared with other masters, etc., the connection between the master and one pieces is not more complicated than before.

Hereinafter, the present invention will be explained in detail using examples.

Embodiment 1 FIG. 3 is a schematic plan view showing an embodiment of the bubble generator of the present invention. The shapes of the bubble transfer path 12 and the conductor pattern 13 are the same as in the conventional case, but the spacing between the conductor layer and the bubble holding l-9 can be changed between the inner side 31 and the outer side 32 near the bubble transfer path 12. It is characterized by one thing. The position where the spacing is changed is a distance 3:3 from the end X111 of the bubble 1 feeding path 12, which is about 2.about.3 times the bubble diameter. Bubble is transfer route within 133 jf
[Is it a conductor that exists stably due to the nk effect caused by ion implantation? By localizing the magnetic field caused by the tt flow near the transfer path, bubbles can be generated more efficiently.

FIG. 4 is a schematic cross-sectional view taken along a line 14 that crosses the conductor pattern 13. The spacing 23 between the center of the conductor hI and the surface of the nopull retaining layer is the inner side 31 and the outer side 32 of the bubble transfer head.
The spacer 22 is processed to be smaller than the . ;
The left or 32nd side Q') spacing of the 44th factor is common to the spacing of the conductors of the other functional parts. At this time, the spacer 22 is etched and widened to reduce the spacing around the bend of the hairpin-shaped conductor.
;8S4 figure +? ia was formed.

In the case of the 41st bacterium (1 to 1), the minimum tulAL required to generate pull can be reduced to /(minimum tulAL for generating pull) compared to the conventional method, and the generation efficiency can be improved (that is, lower power consumption) than the conventional method.

Furthermore, even if the no-pull generated current value deviates from the upper limit of the operating range by 11111 K due to the rise of the chip 1 island 1&, the generation of pulls can be reduced by localizing the current magnetic field (which is unnecessary) than in the past.

Therefore, the actual operating temperature range is also wide.

In addition, in the part where M<L of the spacer 22, the -C spacer 22 may not exist at all, and the bubble retaining layer 21 and the conductor pattern 13 may be in direct contact with each other.

Embodiment 12 FIG. 5 is a schematic sectional view showing another embodiment of the bubble generator of the present invention. In this case, the film thickness of the spacer 22 remains unchanged and is the same as the conventional one, but the inner side 31 near the transfer path 12
It is characterized in that the thickness of the conductor layer is smaller than that of the outer side 32.

That is, since the spacing 23 between the center of the conductor layer and the surface of the bubble retaining layer is small around the conductor bend, the υ conductor magnetic field is larger and more localized at the conductor bend than before. The same effect as in Example 1 can be obtained in improving the bubble generation characteristics.

Further, the turtle flow buds JW in the conductor of this embodiment can be made small in areas other than the bubble generation portion, which is also effective in reducing power consumption due to conductor resistance. Further, this embodiment is effective even when there is no spacer 22 at all.

Embodiment 3 FIG. 6 is a schematic sectional view showing another embodiment of the bubble generator of the present invention.

In this case, contrary to the embodiment, the spacing 23 between the center of the conductor and the surface of the nopull holding layer is adjusted to the inner side 31 near the transfer path 12.
It is characterized by being larger than the outer 32 ni.

Since the CD element, which is commonly used, uses ion implantation strain, the strain caused by the conductor/gutter also affects the bubble generator characteristics depending on the material properties and ion implantation conditions. FIG. 6 shows an embodiment in which, unlike the first embodiment, distortion caused by the conductor pattern deteriorates the bubble generator characteristics (for example, an error in which bubbles are trapped) due to material characteristics.

In this case, the conductor current bubbles occur and the magnetic field at the position expands and weakens due to the increase in spacing, but due to the weakening of disturbances in the magnetic field caused by the in-plane magnetization layer in the conductor, the magnetic field is essentially localized. Bubble generation characteristics with less malfunction can be obtained.

Note that the spacer 22 exists only on the inside 31 of the transfer path,
There may be none on the outside 32.

As explained above, according to the present invention, compared to conventional C and D element bubble generators, it is possible to provide a bubble generator with better bubble generation characteristics by substantially localizing the magnetic field caused by conductor current. 1) It is possible to achieve the effect of increasing the capacity of the device.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view showing a conventional CD element bubble generator, FIG. 2 is a schematic cross-sectional view taken along line 14 in FIG. 1, and FIG.
4 is a schematic sectional view of Embodiment 1, FIG. 5 is a schematic sectional view of Embodiment 2, and 81￥6 is a schematic sectional view of Embodiment 3. The numbers in the figure indicate the following. 11・・・・・・・・・Bubble, 12・・・・・・・・・
・Bubble transfer path/turn, 13... Conductor pattern, 14... Center line of conductor/turn, 15... Hairpin Conductor narrow part, 2
１・・・・・・・・・Nogupuruho UN, 22・・・・・・
...Spacer i, 23......Spacing, 31......Constant spacing area, 32...31 and Spacing Different areas, 33... Distance between the spacing change position and the end of the transfer path

Claims (1)

[Claims] In the bubble generator of the Fundigi and AS disk bubble element, a conductor layer for bubble generation is provided on a bubble retaining layer in which a bubble transfer path is formed using an ion implantation method, and the thickness center of the conductor layer is and the surface of the bubble retaining layer is changed between the bubble transfer path side and the opposite side with the vicinity of the bubble transfer path as a boundary. bubble generator.