JPH01241086A - Magnetic bubble element - Google Patents

Abstract

PURPOSE:To obtain stable detected signals in a wide bias magnetic field range by providing an isolated ion-implanted area at part of the elongated area where the bubble of a detector is extended. CONSTITUTION:An ion-implanted area 7 is provided at the end section of the hairpin type conductor 1 of a detector. The bubble of the detector is started to elongate by means of stretch pulses 4 and reaches the ion-implanted area 7. Thereafter, the bubble can easily maintain an elongated state between an ion-implanted transfer path 2 and the area 7 while pulses 5 are impressed. Moreover, since the ion-implanted area 7 is isolated, the end section of a stripe- like magnetic domain does not move until annihilator pulses 6 are impressed. Therefore, the magnetic domain is stably elongated until the annihilator pulses 6 are impressed and the leakage magnetic field from the magnetic domain is supplied to a detecting line 3. As a result, stable detected signals can be obtained by means of the magneto resistance effect of the detecting line.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an ion implantation type magnetic bubble memory device, and in particular to a detector for a magnetic bubble device that has good operating characteristics and is suitable for obtaining a large detection output. Regarding.

[Conventional technology]

In conventional ion implantation type magnetic bubble probes, the functional part that converts the presence or absence of magnetic bubbles into electrical signals when reading information uses a thin film permalloy pattern as shown in JP-A-58-70479. The detector used is known. Furthermore, since the detection signal is insufficient in this method, a detector using a bent thin film permalloybatan as described in Japanese Patent Laid-Open No. 59-77695 has been proposed.

[Problem to be solved by the invention]

The above-mentioned conventional technology does not take into account the fluctuation of the detection signal due to changes in the bias magnetic field, and there is a problem in operating the detector with a sufficient bias magnetic field margin.

In the detector, as shown in Fig. 2, by applying a current pulse to the conductor pattern 1, the bubble on the ion implantation transfer path 2 is stretched in one direction into a strip-shaped magnetic domain several tens of times the diameter of the bubble. Using the magnetoresistive effect of the thin film Permalloy 3 to which a constant current is applied due to the leakage magnetic field generated from the magnetic domains, the presence or absence of bubbles is detected as a voltage change across the thin film Permalloy. The current pulse applied to the conductor pattern 1 is a two-step pulse as shown in FIG.
It is possible to reduce the pulse duty ratio of the conductor pattern 1 and extend the life of the conductor.

The first pulse 4 serves to extend the bubble B on the ion implantation transfer path 2 beyond the ion implantation boundary to the end. The second pulse 5 has the function of holding the stretched strip-like magnetic domain. In addition to this, a third pulse 6 is required to eliminate bubbles.

The problem with this method is that while the second pulse 5 is applied, the elongated bubble gradually contracts or the end of the elongated bubble moves, resulting in a decrease in leakage magnetic flux from the bubble, and the detection output This results in a decrease in

As one way to solve this problem,
As shown in No. 79, a method has been proposed in which the tip of a strip magnetic domain extending from a first ion implantation transfer path is attracted to a second ion implantation transfer path. However, in this method, when the direction of the rotating magnetic field changes, the attracting magnetic pole of the second ion implantation transfer path moves, causing the strip magnetic domain to move, so that a sufficient effect cannot be obtained.

An object of the present invention is to provide a detector that can stably obtain a detection signal in a wide bias magnetic field range in an ion implantation type magnetic bubble element.

[Means to solve the problem]

The above object is achieved by providing an isolated ion implantation region in a portion of the elongated region over which the detector bubble extends.

[Effect]

In the detector of the present invention, the bubble is stretched inside the hairpin pattern 1 when a pulse current is applied to the hairpin conductor pattern 1 shown in FIG. The striped magnetic domain enters the isolated ion implantation region 7 provided in the ion implantation region 7, thereby causing the striped magnetic domain to extend from the cusp on the major line to the ion implantation region 7. In conventional detectors, the end of one force of the stretched Nidrive-like magnetic domain could move freely, so when a two-step stretch pulse was applied.

Striped magnetic domains tend to shrink, but in the present invention, they can be forcibly held by the attractive force of the ion implantation boundary, so they do not shrink.

Furthermore, since the ion implantation region 7 is isolated, the ends of the striped magnetic domains do not move until the annihilation pulse 6 as shown in FIG. 3 is applied. Therefore, the striped magnetic domain stably extends until the annihilation pulse 6 is applied, and the leakage magnetic field from the 6J& area is supplied to the detection line, and a stable detection signal can be obtained due to the magnetoresistive effect of the detection line.

〔Example〕

Embodiments of the present invention will be described below with reference to FIG. 1 and FIGS. 4 and 5.

The first embodiment has a structure in which an ion implantation region 7 is provided at the end of a hairpin conductor 1 of the detector, as shown in FIG. The bubble begins to stretch due to the stretch pulse 4 and reaches the ion implantation region 7. While pulse 5 is being applied after this.

The expanded state of the bubble between the ion implantation transfer path 2 and the region 7 can be easily maintained. This eliminates fluctuations in the detector signal.

In the second embodiment, as shown in FIG. 4, the detection line 3 of the thin film permalloy is not bent but is linear, and the non-ion implantation pattern 8 in the portion where the bubble extends is made thinner to form the ion implantation region 7. This is an example where . This eliminates unnecessary bubble movement on the low bias magnetic field side and stabilizes the detection signal. - In the third embodiment, as shown in FIG. 5, the detection line 3 is bent and an ion implantation area 7 is provided, and the ion implantation area 9 is also provided in most of the area where the bubble extends.
It has a structure with In this structure, although the detection signal strength is slightly reduced, the attraction force generated on the side surface of the ion implantation region 9 is more effective against signal fluctuations due to changes in the bias magnetic field.

〔Effect of the invention〕

According to the present invention, in an ion implantation type magnetic bubble device, a detector can be configured that has little variation with respect to changes in a bias magnetic field, so that the reliability of the device can be further improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an element showing a first embodiment of the present invention;
FIG. 2 is a plan view showing an example of a conventional detector, FIG. 3 is a diagram of operating pulse waveforms of the detector, and FIGS. 4 and 5 are plan views of elements showing other embodiments of the present invention. It is. 1... Conductor pattern for magnetic bubble expansion, 2
...Ion implantation transfer path, 3...Detection line, 4...
1st bubble stretching current pulse, 5... 2nd bubble stretching current pulse, 6... bubble erasing current pulse, 7... ion implantation region, 8... non-ion implantation slam, 9 ...Ion implantation area. Mel 2 $2 Figure Figure 3 (, Q) (b)

Claims (1)

[Claims] 1. In a magnetic bubble detector that includes an ion implantation transfer path formed by selectively implanting ions, a hairpin-shaped conductor pattern that intersects with the ion implantation transfer path, and a detection line formed of a magnetic thin film, the hairpin type A magnetic bubble element characterized in that at least one or more ion implantation region is provided in a part of a magnetic garnet film near a conductor.