JPS62219284A - Magnetic bubble memory element - Google Patents

Abstract

PURPOSE:To quantitatively control the shape degree of a magnetic bubble transfer path by providing a control pattern consisting of a pattern group which varies continuously in at least one of inclination, interval, and width to the space part of a magnetic bubble memory chip. CONSTITUTION:A control pattern MP consists of a pattern MP1 for shape control formed by uniting two rod-shaped patterns 20 with pattern width (w) while a gap (g) of a tilt angle theta is left and a pattern MP2 for scale control which is formed by arraying rectangular patterns 21 in a longitudinal direction at the side parts of the rod shaped patterns 20 at equal intervals. If the shape control pattern MP1 which varies in gap (g) continuously with the tilt angle thetais left as a pattern residue 22 after a magnetic bubble memory element is completed without being etched completely as shown the hatched part of the gap (g), the size of the area of the pattern residue 22 corresponds to how inferior the shape degree of the monitor pattern MP is. The peak part of the pattern residue 22 is read on the adjacent pattern MP2 for scale control and thus evaluated quantitatively.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic bubble memory device having a management pattern for managing a magnetic puzzle transfer path.

[Conventional technology]

In recent years, as a magnetic bubble memory element that has realized high density and high speed magnetic bubble memory, for example, Japanese Patent Application Laid-Open No. 57-18
As disclosed in Japanese Patent Application No. 6287, a group of minor loops that store information in the form of magnetic bubbles is configured with an ion implantation type magnetic bubble transfer path, and at least a part of the connecting portion with the major line or major loop that transfers the magnetic bubbles is constructed. A so-called hybrid type magnetic bubble memory element configured with a permalloy type magnetic bubble transfer path has been proposed.

[Problem that the invention seeks to solve]

A magnetic bubble transfer path using an ion implantation method (hereinafter referred to as an ion implantation transfer path) and a magnetic bubble transfer path using a permalloy method (hereinafter referred to as a permalloy transfer path) used in this type of magnetic bubble memory element are several μm thick.
The minimum pattern dimension is an ultra-fine pattern with a pattern period of about 100 yen, and the minimum pattern dimension is submicron. For this reason, when mass-produced, these dimensions have some variation, and this variation in dimensions greatly influences the characteristics of the magnetic bubble memory. Therefore, strict control of the dimensions of these ultra-fine patterns is extremely important for mass production.

To improve these problems, it is efficient to use the space around the magnetic bubble memory element to provide a management pattern, and this pattern is used for management. Ta.

This type of management pattern is shown in Figure 10 (-) and (b).
, line and space (t,
&S) Pattern 1, known as a strip-shaped pattern
It is composed of a pattern group formed by arranging a plurality of 0's in parallel at equal intervals. That is, in the figure, when the pattern width of each strip pattern 10 is W and the pattern gap is g, normally w = g = a, and the value of a is 0 in the figure (a). .5μm, Φ in the same figure) is 0.75μfl
In the same figure (c), it is made up of a group of patterns having a plurality of different sizes, such as 1.0 μm. This management method has been carried out by examining short-circuited patterns.

However, such a method is not suitable for quantification and is insufficient when the magnetic bubble transfer path has an ultra-fine pattern.

An object of the present invention is to provide a magnetic bubble memory device having a management pattern that can quantitatively manage even ultra-fine patterns.

[Means for solving interlayer points]

According to one embodiment of the present invention, an ultra-fine pattern is formed by providing a management pattern in a spatial portion of a magnetic bubble memory chip, which is made up of a pattern group in which at least one of the widths of at least one slope of one interval and nine widths changes continuously. Provided is a magnetic bubble memory element that can quantitatively manage the degree of formation of magnetic bubble transfer paths.

[Effect]

In the management pattern according to the present invention, the shape of the pattern remains as a tangible material, so by reading the continuous change in shape of the pattern, it is possible to infer whether the magnetic bubble transfer path has been formed properly or not.

〔Example〕

Next, embodiments of the present invention will be described in detail using the drawings.

FIG. 5 is an enlarged plan view illustrating a magnetic bubble memory device according to the present invention. In the figure, m is a minor loop that stores information, RML is a read major line that transfers read information, and wNL is a write major line that transfers write information. Further, D is a bubble detector that converts magnetic bubbles into electrical signals, G is a bubble generator that generates magnetic puzzles, and R is a replicate gate that copies or transfers the information of the minor loop m to the read major line: yRML. T is a transfer gate that transfers the information on the light major line WML to the minor lube m, or a swap gate that simultaneously with the transfer, sweeps out the information on the minor lube m to the major line WML, so-called exchanging information between the two. Furthermore, GR surrounding these outer peripheries is a guardrail that prevents magnetic bubbles from entering from the outer periphery, BP is a bonding pad for connecting these transfer circuits with external circuits, and MP is a guardrail inside the magnetic bubble memory chip CHI. This is a management pattern formed outside the effective area indicated by a broken line. Also, replicate gate R,
The swap gate T and the bubble generator G are controlled by whether or not a current flows in a certain direction through a conductor in a separate layer arranged in a special relationship with the permalloy transfer pattern, and the conductor portion is shown by a thick solid line in the figure. has been done. In addition, the minor loop m is formed by a magnetic bubble transfer path by ion implantation, and the read major line RML, write major line WML, etc. are formed by a permalloy magnetic bubble transfer path, and a bias magnetic field Ha is applied perpendicularly to these surfaces. The magnetic bubbles are transferred in the directions shown by the arrows by the continuously rotating magnetic field Hm applied in the plane.

Figures 6 and 7 show the permalloy transfer path mentioned above.

Each of the ion implantation transfer paths is shown, and the permalloy transfer path P shown in FIG.
A soft ferromagnetic thin film pattern PT, such as permalloy, is formed on top of the pattern PT via a spacer film sp such as 8101. A rotating magnetic field H1 that rotates this pattern PT within this pattern plane
By magnetizing with , a moving magnetic pole Q is formed. The magnetic bubble B is attracted to the moving magnetic pole Q and is transferred along the pattern PT in the direction of the arrow PR. On the other hand, in the ion implantation transfer path construction, as shown in Fig. 8, ions appear from a thin film pattern such as a heat-resistant resin film or metal thin film on the magnetic bubble magnetic film LPE corresponding to the non-ion implanted region. After forming the implantation mask MSK, H! is applied to the surface of this magnetic bubble magnetic film LPE. “+ He”,
By implanting ions such as N@+, an ion-implanted layer ION in which ions are implanted is formed in the region other than where the mask MSK is formed, and an ion-implanted transfer butter yIPT is implanted in the region where the mask MSK is formed. Note that when H2 is used for ion implantation, it may be implanted after providing passivation 1aps as shown in FIG. 9 in order to prevent its evaporation.

In either case, after ion implantation, the mask pattern MSK is removed, and an ion implantation transfer path structure as shown in FIG. 7 is formed. The ion implantation transfer path construction constructed in this manner magnetizes the ion implantation layer ION with a rotating magnetic field H11 that rotates within the pattern plane.
A magnetic pole Q, called a charged wall, is generated that moves along PT.

The magnetic bubbles are attracted to this charged wall and transferred along the pattern rPT in the direction of the arrow PR.

As shown in FIG. 6, the ion implantation transfer path I has no gap between patterns compared to the permalloy transfer path PK, and the ion implantation layer ION is formed inside the puzzle magnetic gLPE, resulting in magnetic bubbles. The feature is that it is closely spaced from B, and due to the breakage, excellent characteristics can be obtained for high density.

The per-ffO transfer path P and ion implantation transfer path I, which have such features and are suitable for high density, require strict quantitative control of their dimensions in mass production when their pattern shapes are ultra-fine. was not possible.

Therefore, in the magnetic bubble memory device according to the present invention, the above-mentioned management butter yMP is such that the two bar-shaped patterns 20 having the pattern @W are arranged at an angle of inclination θ as shown in FIG. 1(a).
A shape management pattern MP1 integrally formed with a gap g of It is configured.

According to such a configuration, the shape management pattern MP1 in which the gap g continuously changes with the inclination angle θ is created by the two bar-shaped patterns 20 after the magnetic bubble memory element is completed, as shown in FIGS. If the pattern is not completely etched away and remains as a pattern residue 22 as shown by the hatched area in the gear g section, this pattern residue 22
It means that the larger the area, the worse the degree of formation of the monitor pattern MP. Then, by reading the top of this pattern residue 22 with the adjacent scale management pattern MP2, quantitative evaluation can be performed.

Figures 2 to 4 are management patterns MP according to the present invention.
The management pattern MP shown in FIG. 6D and FIG. a shape management pattern MP3 integrally arranged and formed so as to be small in size, and a scale management pattern MP2 in which rectangular patterns 21 are arranged and formed at equal intervals along the length direction on the side of the rod-shaped pattern 2G. It consists of Second
The management pattern MP shown in Figure (b) is a pattern obtained by removing the narrow part of the gap g in Figure (a),
Basically, the same effect as in FIG. 1 can be obtained by the same operation. The management pattern MP shown in FIG. 3 is composed only of a shape management pattern MP4 formed by radially arranging a plurality of bar-shaped patterns 30. Also, the fourth
The management pattern shown in FIG. The shape and scale management patterns MP6 are arranged orthogonal to each other at an inclination angle θ with respect to the shape and scale management patterns MP6. Furthermore, the management pattern MP shown in FIG. 4(b) is formed by arranging the shape management pattern MP5 shown in FIG. It is composed of a shape and scale management pattern MP7 formed by.

The various management patterns MP configured in this manner are formed, for example, on the magnetic bubble magnetic film LPE with a thin metal film such as Au or a thin film of resin such as heat-resistant polymer resin, as explained in FIG. Ion implantation mask MSK
At the same time as the formation of the mask MSK, after ion implantation, only the mask MSK is removed and the remaining part is used to form the mask MSK. By quantitatively evaluating the degree of shape of the management pattern MP, it is possible to quantitatively manage the degree of formation of the ion implantation transfer path I formed by the removed mask MSK. Note that when these management patterns MP are formed of a resin thin film, they can be read by a dimension measuring means that measures the distance between the pattern edges.

Further, various management patterns MP configured in this way are, for example, magnetic bubble magnetic film L as explained in FIG.
At the same time as the permalloy pattern PT formed of permalloy on PE via the spacer SP, the permalloy pattern is simultaneously formed on the same layer. By quantitatively evaluating the degree of shape of this management pattern MP, it is possible to quantitatively manage the degree of formation of the permalloy transfer path P formed at the same time.

In the above-mentioned embodiment, the case where the management pattern MP was provided in the side space of the magnetic bubble detector was explained, but the present invention is not limited to this, and the management pattern MP is provided in the periphery of the chip CHI, etc. Of course, the same effect as described above can be obtained even if it is provided in the space of .

〔Effect of the invention〕

As explained above, according to the present invention, since a management pattern consisting of a pattern group in which at least one of two slopes and one width continuously changes is provided in the spatial part of the magnetic puzzle memory chip, the degree of shape of this management pattern is By evaluating this, an extremely excellent effect can be obtained in that the degree of formation of the magnetic bubble transfer path can be quantitatively controlled.

[Brief explanation of drawings]

1(-) and 1(b) are plan views of management patterns for explaining one embodiment of the magnetic bubble memory device according to the present invention, and FIGS. 2 to 4 illustrate other embodiments of the present invention. 5 is a plan view showing a magnetic bubble memory element according to the present invention, FIG. 6 is an enlarged perspective view of essential parts showing a permalloy transfer path, and FIG. 7 is an ion implantation transfer path. Figures 8 and 9 are enlarged perspective views of the main parts to explain the method of forming the ion implantation transfer path, and Figures 10 (-), (b), and (C) are conventional management. FIG. C) II... Magnetic bubble memory chip, MP Φ
・Management pattern, MPI, MP3. MP4・Fist--Pattern for working shape management, MP2・・・・Pattern for scale management, 〼←MP5・・・・Pattern for shape management, MP6
, MP 7... Pattern for shape and scale management, 2
0.30... Bar pattern, 21,40... Rectangular pattern, 22...@φ pattern residue, 50...
・Rhombus pattern.

Claims (1)

[Claims] 1. The spatial part of the magnetic bubble memory chip has slope, spacing,
1. A magnetic bubble memory device, characterized in that a management pattern is provided which is made up of a group of patterns in which at least one of the widths changes continuously.