JPS61131285A - Manufacture of magnetic bubble memory element - Google Patents

Abstract

PURPOSE:To obtain a magnetic bubble memory element to prevent a malfunction by exposing an ion implantation layer of a bubble garnet membrane to a plasma of rare gas or hydrogen gas, increasing an inductive anisotropic magnetic field, forming the first spacer layer and suppressing an abnormal bubble. CONSTITUTION:A bubble garnet film 12 is formed on a GGG substrate 11, Ne<+> ion is implanted to a film 12, and an ion implantating layer 13 is formed in which the shaft to magnetize easily the magnetic anisotropy of the surface of the membrane 12 is parallel to the membrane 12. The substrate 11 forming the layer 13 is exposed to an Ar gas plasma or a H2 gas plasma or inert gas of Ar gas, etc., including hydrogen or a hydrogen plasma and an inductive anisotropic magnetic field of the implantation layer 13 is further increased. Next, by using an insulating material of SiO2, etc., onto the layer 13, the first spacer layer 14, a conductor pattern 15, an inter-layer film 16 of SiO2, etc., a driving pattern 17 and a protective film 18 are formed in order. Thus, the layer 13 to suppress an abnormal bubble is easily formed, and the bubble memory element, which prevents a malfunction, is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a magnetic bubble memory device, and particularly to a method for suppressing abnormal bubbles in the device.

[Conventional technology]

Non-magnetic gadolinium-gallium garnet substrate (Gd3
A magnetic bubble crystal film was grown on a Gas 012 substrate (abbreviated as GGG substrate) by liquid phase growth method (LP [! method)].
Ions are implanted into this crystal film (the axis of easy magnetization is perpendicular to the plane) to change the axis of easy magnetization to a direction parallel to the plane, thereby suppressing abnormal bubbles.

The magnetic bubble memory element (also called chip) is the fourth
It is shown in the cross-sectional view of the figure, and in the figure, 41 is a GGG substrate;
42 is a magnetic bubble crystal film, 43 is a 5i02 first spacer, and 44 is Au or Aj! -Cu conductor pattern, 45 is SiO2 or PLO3 (Poly Lad
derOrgano 5iloxane) insulating film,
Reference numeral 46 indicates a drive pattern of permalloy, 47 indicates a protective film of SiO+ or PLO3, and the above-mentioned ion implantation layer is a portion indicated by reference numeral 48.

[Problem that the invention seeks to solve]

Conventionally, Ne+ ions were implanted into the crystal surface in order to suppress abnormal bubbles that cause malfunctions, but with this method, it was only possible to obtain an anisotropic magnetic field change of about 25,000e, which caused a large There is a problem in that microbubble crystals with perpendicular magnetic anisotropy cannot sufficiently suppress abnormal bubbles.

[Means for solving problems]

The present invention provides a method for suppressing abnormal bubbles that solves the above-mentioned problems.The method involves implanting ions into the entire surface of a magnetic bubble crystal film, and then exposing the crystal film to plasma of an inert gas. A method for manufacturing a magnetic bubble memory device is performed, which is characterized in that the induced anisotropy field in the layer is increased and then a first spacer is deposited.

C effect] The purpose of the present invention is to provide a method for sufficiently suppressing abnormal bubbles for bubble crystals with large perpendicular magnetic anisotropy, and the ion-implanted layer of the bubble garnet film is injected with rare gas or hydrogen. This method takes advantage of the fact that the induced anisotropic magnetic field Δl+k increases significantly when exposed to plasma, and uses this to suppress abnormal bubbles.

〔Example〕

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

Figure 2 is a diagram showing the Ne+ ion dose dependence of ΔHk of the ion-implanted layer exposed to plasma, where the horizontal axis represents the dose (Ne+(XIOI'l/cm2)) and the vertical axis represents the anisotropic The magnetic field change A11k is expressed as [Oe]. Without plasma treatment shown in line A, ΔIlk is up to 250
00e, but if the plasma treatment shown by line B is performed, Δ
Ilk is seen to increase more than 2-fold.

FIG. 1 shows a cross-sectional view of a magnetic bubble memory element according to an embodiment of the present invention. In the figure, 11 is a GGG substrate, 12 is a magnetic garnet film, 13 is an ion-implanted layer, and 14 is a silicon dioxide (5i02) layer. 1 spacer, 15 conductor pattern, 16 I'LO5 (Poly l, add
erOrgans 5iloxane) or SiO
2, I7 is a permalloy driving pattern, and 18 is a protective film of SiO2, Pl, or O3.

Ne+ ions are implanted into the magnetic garnet film 12 grown to a thickness of 1 pm on the GGG substrate 11 by the LPE method. The ion implantation conditions were an acceleration energy of 20 to 50 KeV, and a dose of 5 x 1013Ne''/
cm2 to 1×101'INe+/Cff12. As a result, the magnetic anisotropy of the surface of the magnetic garnet film 12 changes, and the ion-implanted layer 13 whose axis of easy magnetization is parallel to the in-plane
is formed.

Thereafter, the substrate is exposed to Ar gas plasma using the plasma apparatus shown in FIG. In Figure 3, 11 is GG
G substrate, 31 is a cathode electrode, 32 is an anode electrode, 3
3 is an argon or hydrogen gas inlet, 34 is a high frequency (R
F) Power supply, 35 is a vacuum exhaust port, 36 is a vacuum chamber,
, plasma is generated between the electrodes 31 and 32, and the ion-implanted layer of the magnetic garnet film of the substrate is exposed to the plasma.

As a result of exposure to plasma as described above, the ion-implanted layer 13
It was confirmed that the anisotropic magnetic field change Δl (k) was increased, the magnetization became completely parallel to the plane, and a good abnormal bubble suppression layer was formed. The manufacturing process forms the chip shown in Fig. 1.The same effect was obtained by using hydrogen gas plasma instead of Ar gas plasma.

As explained above, according to the present invention, it is possible to easily form an abnormal bubble suppression layer even in a microbubble material having a large anisotropic magnetic field Hk by implanting Ne+ ions and exposing it to plasma. This is effective in preventing malfunction of memory elements.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a diagram for explaining the present invention in detail, and FIG. 3 is a plasma processing apparatus,
FIG. 4 is a sectional view of a conventional magnetic bubble memory element. In the figure, 11 is a GGG substrate, 12 is a magnetic garnet film, 1
3 is an ion implantation layer for suppressing abnormal bubbles, and 14 is a first layer.
a spacer, 15 a conductor pattern, 16 an interlayer film,
17 is a drive pattern, 18 is a protective film, 31 is a cathode electrode, 32 is an anode electrode, 33 is a gas inlet, 34 is D
I' power supply, 35 is a vacuum exhaust port, 36 is a vacuum chamber,
are shown respectively. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In the permalloy bubble device manufacturing process, after ion implantation is performed on the entire surface of the magnetic bubble crystal film, the crystal film is exposed to plasma of an inert gas, hydrogen gas, or an inert gas containing hydrogen, and the induced anisotropy within the ion implanted layer is A method for manufacturing a magnetic bubble memory device, comprising increasing a magnetic field and then depositing a first spacer.