JPS60145592A - Magnetic bubble element - Google Patents

Abstract

PURPOSE:To prevent a charged wall from becoming weak by setting an in-plain magnetic anisotropic magnetic field of an ion implanting layer to a prescribed value in a contiguous disk ion implanting magnetic bubble element. CONSTITUTION:When a pattern of 3,000Angstrom of SiO2 is formed on an ion implanting layer 22 due to double implantation and anealed at 250 deg.C, etc., in a hydrogen gas atmosphere, an in-plain anisotropic magnetic field becomes maximum in a pattern edge 25 due to diffusion of hydrogen, and it becomes smaller as it goes away from the field. In a center of a pattern it becomes minimum, and a value of the in-plain magnetic anisotropic magnetic field of the maximum part becomes larger than that of the minimum part by >=10%. As a result, an in-plain anisotropic magnetic field value becomes larger without any increase in implantation distortion of an ion layer, and a charge in the reverse direction of a charged wall will not occur near the charged wall. As a result, weakening of a charged wall can be prevented, a magnetic bubble element needs low power consumption and becomes high reliable and a high density.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a contiki ass disk ion implantation bubble device, and more particularly to a distribution shape of an anisotropic magnetic field in an ion implantation layer in the vicinity of a contiki ass disk pattern edge.

Ion-implanted bubble elements are created by forming a continuous disk-shaped mask pattern with gold or the like, then implanting ions with helium ions, etc., and then transferring magnetic bubbles through a charged wall created in the ion-implanted layer near the edge of the pattern. It is a bubble element. In such an ion-implanted bubble device, smooth movement of a strong charged wall is required to ensure stable transfer of bubbles. Journal of Applied
Physics Vol. 53, p. 5815 (Jarnalof
Applied Physics, Vol. 5
3 + 5815), a charged wall is formed based on the relaxation of strain near the pattern edge, so in order to strengthen a charged wall, increasing the implantation strain in the ion-implanted layer will reduce the strain. It also makes me stronger. However, when the strain is increased and the in-plane anisotropic magnetic field is increased, as shown in Figure 1, a charge with the opposite sign to that of the charged wall is generated at the pattern edge near the charged wall, and the charge is The charge also becomes stronger.

As a result, the charged wall becomes weaker or the bubble transfer becomes unstable, which is a technical problem of the ion-implanted bubble device.

The present invention provides a solution to the problems of charged wall formation in conventional ion implantation bubble devices described above.

That is, in the element of the present invention, the in-plane magnetic anisotropy field of the ion-implanted layer is maximum at the edge of the pattern, and gradually decreases as it moves away from the edge of the pattern.
The minimum value of the in-plane magnetic anisotropy field is at least 10% larger than the minimum value at the center between the transfer loops.

The present invention will be described in detail below with reference to examples.

Y on GGG board. , 38 m. , 2 L u 1.
46 B 1 '6.3Ca o, 75B' e, 2
A garnet having a composition of 5G e o4g O□2 was formed by the LPE method. After forming a contiki ass disk pattern mask using gold, s He 'e (100 keV
.

3.8X101'//Ctl)T (40keV,
Double ion implantation was performed under the conditions of 1.8×1 o15/Cn). The gold mask pattern was peeled off to form a pattern (23) with a thickness of 5i023,000 on the ion-implanted layer (22) as shown in FIG. Next, in a hydrogen gas atmosphere,
Annealing was performed for 10 minutes at 0°C.

By performing such a process, Figure 2 (24)
As shown, the in-plane anisotropic magnetic field is maximum at the pattern edge portion (25) and minimum at the center under the pattern 5i02. As shown in Japanese Patent Application No. 58-126716, by performing hydrogen atmosphere annealing, hydrogen diffuses into the ion implanted region, increasing the anisotropic magnetic field change ΔHk in that region. This is based on the effect. Bubble elements manufactured using this process have the following advantages. First, the minimum driving peak field was reduced by about 100e. This seems to be due to the enhanced anisotropy along the pattern edges. Second, the minimum bias magnetic field was lowered by about 100e, and the bias margin was expanded. This is because the error caused by bubbles jumping between loops has been reduced. When the difference between the maximum value and the minimum value of the in-plane magnetic anisotropy field was less than the minimum value of 010%, no improvement effect was observed within the experimental error range.

The mask for hydrogen gas atmosphere annealing formed on the ion-implanted layer may be made of an inorganic material such as Al2O5, or a metal material such as Au, in addition to 5i02, with similar effects. Moreover, the shape can be formed along the pattern at a distance of approximately 1 μm (in the case of a 4 μm periodic pattern) from the pattern edge as shown in FIG. 3, or simply between the loops as shown in FIG. A similar effect can be obtained even with a simpler shape such as a striped mask. Furthermore, since this technique can suppress jumps between loops, it is also possible to reduce the loop period from an 8 μm period for a conventional 1 μm bubble to a 7 μm period.

As described above, according to the present invention, lower power consumption, higher reliability, and higher density of magnetic bubble elements can be achieved.

[Brief explanation of drawings]

Figure 1 shows a charged wall and charges with opposite signs that occur when the in-plane magnetization component increases, and Figure 2 shows the mask and in-plane magnetic annealing formed on the ion-implanted layer for hydrogen atmosphere annealing. A diagram showing that the directional magnetic field -HkI is minimum at the center of the mask and maximum at the edge of the shield. Figures 3 (a) and (b) are planes showing the shape of the mask for hydrogen gas annealing, respectively. The figure and the sectional view and FIGS. 4(a) and 4(b) are a plan view and a sectional view showing other mask shapes, respectively. In the figure, 31.41.゛°°°°non-ion implantation pattern, 32.42...mask, 33.43.
...Ion implantation layer. Figure 1 14 1 Second Figure 3 (ri) 3 Longevity Figure 4 (8)

Claims (1)

[Claims] In a continuous disk ion-implanted magnetic bubble device, the in-plane magnetic anisotropy field of the ion-implanted layer is maximum at the edge of the continuous disk pattern, and as it moves away from the edge, The minimum value of the in-plane magnetic anisotropy is at least 1 °C in the middle between the transfer loops, and the maximum value of the in-plane magnetic anisotropy is at least 1 °C smaller than the minimum value.
A magnetic bubble element 3 characterized by being larger than 0%,