JPS6254889A - Magnetic bubble device - Google Patents

Abstract

PURPOSE:To improve yield in the manufacture of magnetic bubble chips by fixing two or more pieces of individual blocks on an auxiliary substrate and constituting the magnetic bubble chips having a desired storage capacity, thereby making it possible that the said blocks whose center value of bias magnetic field are close are combined. CONSTITUTION:A wafer 4 provided with plural pieces of chip constituting elements 41 and a cutting space 42 for dividing the chip constituting element 41 is cut to form a piece 51 having a single chip constituting element 41 or two or more pieces of the element 41. The two or more pieces of said block 51 are fixed on the auxiliary substrate 6 complying to a positioning means provided on the substrate 6 to form the magnetic bubble chip 5 of desired storage capacity. As a result, the probability that neighboring two pieces of the chip-constituting elements are all made to good product and their center values of bias magnetic field become close, is made higher, comparing with that of that neighboring four pieces.

Description

[Detailed Description of the Invention] [Summary] In the manufacture of magnetic bubble chips, as the storage capacity per chip increases, the defective rate is assimilated in a geometric progression.

Therefore, a magnetic bubble chip having a desired storage capacity is constructed by fixing a plurality of individual pieces each having a chip component on an auxiliary substrate, thereby reducing the increase in manufacturing cost due to a decrease in yield.

[Industrial application field]

The present invention relates to a magnetic bubble device that controls magnetic bubbles to store and transfer information.

The magnetic bubble device has a magnetic bubble chip and a
It is composed of a drive coil in the Y-axis direction, a bias coil and a magnet that apply a bias magnetic field.

As shown in the schematic diagram of FIG. 2, the storage area of the magnetic bubble chip includes a reading major line M1 equipped with a normal bubble generator GI, a successive major line M2 equipped with a bubble detector S, and a minor line for reading bubbles. A swap or transfer gate G2 for inputting bubbles into the loop, a replicate or transfer gate G3 for reading bubbles from the minor loop, and approximately 300 or 600 storage loops called minor loops m are formed. One information block (one page) is first introduced into the major line M1 from the bubble generator, and when this is in front of each gate G2, each gate is opened at the same time, and the information block is stored in the minor loop m. . When reading information in the minor loop m, when the information block comes in front of each gate G3, the gates are opened all at once and the information is transferred to the major line M2. This is major line M2
♂ In such a magnetic bubble device, when the bias magnetic field increases beyond the optimum bias magnetic field value, the magnetic bubble disappears and this phenomenon is called collapse), and the bias magnetic field becomes the optimum bias value. When the magnetic field becomes smaller than the magnetic field value, the magnetic bubbles connect in a strip-like manner (this phenomenon is called strip-out).
. The center value of the bias magnetic field that does not cause collapse and strip-out varies depending on the magnetic bubble chip, and even if you aim for around 210 oersted (Oe) as the target value, ±
There is a "variation" of about 20 oersteds (Oe),
There is "variation" even between minor loops formed on the same magnetic bubble chip.Moreover, the bias margin for the optimum bias magnetic field value is ±10 Oe.
).

Therefore, in order to reduce the manufacturing cost of magnetic bubble devices, it is necessary to take measures to reduce the "dispersion" of the bias magnetic field and improve the yield of magnetic bubble chips.

[Conventional technology]

FIG. 3 is a perspective view of a conventional magnetic bubble knob.

In the figure, 1 is a magnetic bubble chip, 2 is an auxiliary substrate, and 3 is a substrate. The magnetic bubble chip 1 is fixed to the surface of the auxiliary base &2, and the auxiliary substrate 2 is fixed to the substrate 3 having a window 31 for accommodating the magnetic bubble chip 1. Although not shown, a conductive pattern is formed on the base@3 by printing, and the magnetic bubble chip 1 and the conductive pattern on the substrate 3 are electrically connected by a metal wire, and the X-axis is connected to the substrate 3 from above. A drive coil in the direction and a drive coil in the Y-axis direction are wound.

In a magnetic bubble device with a storage capacity of approximately 5.5 to IMb, it is possible to configure a minor loop m corresponding to the entire storage capacity in the storage area of the magnetic bubble chip shown in the schematic diagram of FIG. But for example, if the storage capacity is 4? Ib
In a magnetic bubble device of about 100%, configuring a minor loop m corresponding to the entire storage capacity in the 1g area marked by the magnetic bubble chip shown in the schematic diagram of FIG. It is also disadvantageous when configuring. Therefore, a chi-nob component 11 equivalent to the magnetic bubble chip shown in the schematic diagram of FIG. 2 having a storage capacity of about IMb is formed on a wafer, and
The wafer is cut so that four chip components 11 are included in the magnetic bubble chip l.

[Problem that the invention seeks to solve]

However, as mentioned above, the center value of the bias magnetic field that does not cause collapse and strip-out varies depending on the magnetic bubble chip, and even if the target value is around 210 Oe, there is a variation of about ±20 Oe. There are also "variations" between the minor loops formed in the magnetic bubble chip.Moreover, the bias margin for the optimum bias magnetic field value is only about ±10 Oe.

Therefore, even if magnetic bubble chips are formed on the same wafer, some magnetic bubble chips will be defective, and the probability that all four adjacent magnetic bubble chips, that is, chip components, will be good is low. Furthermore, since the center values of the bias magnetic fields are close to each other, the probability of driving under the same conditions further decreases.

For this reason, one magnetic bubble chip has 4 folds.
Conventional magnetic bubble devices configured to include chip components have had the problem of low yield of magnetic bubble chips and high manufacturing costs (...i) [Means for solving the problems] FIG. 1 is a perspective view showing an embodiment of the present invention.

The above problem is caused by a plurality of chip components 41 having arbitrary storage capacities shown in FIG.
After cutting the wafer 4 having a cutting space 42 for dividing into pieces to form individual pieces 51 having one chip component 41 or two or more chip components 41, the process shown in FIG. In accordance with the positioning means provided on the auxiliary board 6 shown in FIG. This problem is solved by the magnetic bubble device of the present invention, which comprises a magnetic bubble chip 5 having the following structure.

[Effect] Compared to the probability that all four adjacent chip components will be good products and the center values of the bias magnetic fields will be close to each other,
The probability that these chip components will be good and the center values of the bias magnetic fields will be close to each other is much higher. Furthermore, Figure 1 (C1
As shown in the figure, two or more individual pieces are fixed on an auxiliary substrate to form a magnetic bubble chip having a desired storage capacity, thereby combining two or more individual pieces whose center values of bias magnetic fields are close to each other. becomes possible. Therefore, the yield of magnetic bubble chips can be improved and the manufacturing cost of magnetic bubble devices can be reduced.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to FIG.

As shown in FIG. By cutting as shown in FIG. 2, pieces 51 including two chip components 41 are obtained. That is, each piece is constructed to have a capacity of 2 Mb.

By combining two such individual pieces 51, a magnetic bubble device having a storage capacity of 4 Mb can be constructed. However, if the arranged 2F fixed f pieces 51 are not arranged on parallel lines, the phase characteristics of each gate will differ and the bias margin will decrease. In addition, in the correct area where the quality of the magnetic field such as drive coils and bias magnets is guaranteed.
If the individual pieces 51 of 2 (1!il) are not placed, the characteristics will deteriorate.Therefore, as shown in Fig. 1, the surface of the auxiliary substrate 6 to which the individual pieces 51 are fixed is polished to a mirror surface.
A reference line 6I is printed on the polished surface to indicate the position when fixing the individual piece 5I.

FIG. 1 (C1) By aligning the two individual pieces 51 with the reference line 61 and fixing them to the auxiliary board 6, a magnetic bubble chip 5 having a storage capacity of 4 Mb is constructed. It is fixed to a substrate 3 having a window 31 for accommodating it.

Compared to the probability that all four adjacent chip components will be good products and the center values of the bias magnetic fields will be close to each other,
The probability that these chip components will be good and the center values of the bias magnetic fields will be close to each other is much higher. Moreover, Fig. 1(e)
By fixing two or more individual pieces on an auxiliary substrate to form a magnetic bubble chip having a desired storage capacity as shown in Figure 2, the center value of the bias magnetic field is close to 2 (+1i
It becomes possible to combine one or more individual pieces. Therefore, it is possible to improve the yield of magnetic bubble chips and reduce the manufacturing cost of magnetic bubble devices.

In this embodiment, a magnetic bubble chip with a storage capacity of 4Mb is constructed using two pieces each having a storage capacity of 2 lungs. A magnetic bubble chip with a storage capacity of 2Mb was constructed using individual pieces, and a magnetic bubble chip with a storage capacity of 4Mb was constructed using four individual pieces with a storage capacity of IMb. °It is also possible.

[First Achievement of the Invention] As described above, according to the present invention, it is possible to provide a magnetic bubble device that enables an improvement in the yield of magnetic bubble chips and a reduction in the cost of VA manufacturing.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a schematic diagram of a magnetic bubble chip, and FIG. 3 is a perspective view of a conventional magnetic bubble chip. In the figure, 3 is a substrate, 4 is a wafer, 5 is a magnetic bubble chip, 6 is an auxiliary substrate, 31 is a window, 4
1 represents a chip component, 42 represents a cutting space, 51 represents an individual piece, and 61 represents a reference line, respectively.

Claims (1)

[Claims] A plurality of chip components (41
) and a cutting space (42) for separating the chip component (41) into pieces, cutting the wafer (4) into one chip component (41) or two or more pieces. After forming the individual pieces (51) having the chip component (41), two or more of the individual pieces (51) are placed on the auxiliary substrate (6) according to the positioning means provided on the auxiliary substrate (6). ) A magnetic bubble device comprising: a magnetic bubble chip (5) having a desired storage capacity;