JPS60254781A - Manufacture of magnetism detector - Google Patents

Abstract

PURPOSE:To eliminate the deterioration in output efficiency, by using the same pattern, performing position matching in self-alignment, thereby realizing the position relationship between a magnetic layer and a conducting layer accurately. CONSTITUTION:As a means of performing accurate position matching, a conducting thin stripe (length: l) is made longer than a magnetic thin stripe (width: W) (W<l), both thin films are sequentially etched from the upper layer and a pattern is formed. A conducting layer 13, which is longer than the width (W) of a magnetic layer 12 is prepared. At this time, a closely contacted layer 16 is simultaneously etched. Then, a new resist layer 18 is used, and the magnetic layer 12 is patterned. Since l is longer than W, it is not required to perform strict position alignment. The conducting layer 13, which is protruded from the magnetic thin stripe, is simultaneously etched when the magnetic thin stripe is formed. Finally, a protecting layer 14 such as SiO2 is prepared, and a terminal corresponding to an outer terminal 5 in Figure 2 is formed by a conductor such as Au. Thus the detector is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION (11) Technical Field of the Invention The present invention relates to a method for manufacturing a magnetic detector (magnetic sensor) that is a barber-ball type magnetoresistive element, and in particular to a method for accurately aligning a magnetic sensor using a self-alignment method. The present invention relates to a method of manufacturing a magnetic detector.

(2) Background of the technology Magnetoresistance 9) In order to detect a magnetic field using the J effect, it is necessary to obtain linearity between the magnetic field and the output. As one means for this, it is possible to obtain a change in magnetic resistance proportional to a change in the magnetic field by providing a large number of conductive ribbons at an angle of 45 degrees to the magnetic ribbon. That is, the resistance ρ of the element is related to the angle θ formed by the direction of magnetization (Ml) and the current ('II),
It is expressed as ρ-ρ, +Δρo CO52θ. Here Δρ
0 = ρ, , -ρ, and ρ, 1 and ρ indicate the specific resistance when the direction of each hat and the current are parallel and perpendicular. Therefore, if a current is passed through a conductive ribbon with low resistance so that θ is 45 degrees, linearity between the magnetic field and the output can be obtained within a certain range as shown by the line in Figure 1. can.

Figure 2 shows a conventional example in a cross-sectional view of fal and a plan view of fb.
A silicon wafer or Pyrex substrate with layers formed thereon is shown. A magnetic thin film 2 of permalloy, nickel-cobalt, etc. is deposited by vapor deposition and sputtering, and a rectangular magnetic thin film 2 is formed by lithography and etching techniques.The direction of magnetization is oriented parallel to the pattern. The above-mentioned linearity improves when the temperature is lowered in a vacuum, and a magnetic field is applied parallel to the strip to create an easy axis of the magnetic field in the longitudinal direction of the pattern.Alternatively, a magnetic film can be attached in the magnetic field. Anisotropy may also be caused.

Next, titanium (Ti) and chromium (Cr) are placed on the ribbon 2.
A conductive film of gold or the like is laminated via an adhesive layer 6 such as the like, and a conductive thin strip 3 is formed by extending 45 degrees with respect to the magnetic thin strip by lithography. Note that when a silicon wafer is used, an insulating film is formed thereon.

(3) Prior Art and Problems Barber-pole type detectors are constructed by forming conductive thin strips on top of magnetic thin strips, and conventionally they have been formed by sequentially stacking layers starting from the lower layer of magnetic thin strips. However, this method has the disadvantage that output efficiency decreases unless the upper and lower layers are precisely aligned.

(4) Purpose of the Invention In view of the above-mentioned conventional problems, an object of the present invention is to provide an efficient manufacturing method for a magnetic detector for accurately aligning a magnetic ribbon and a conductive ribbon. do.

(5) Structure and object of the invention According to the present invention, a method for manufacturing a magnetic detector is provided, in which a conductive layer made of a conductive thin strip is arranged on a magnetic layer made of a magnetic thin strip at an angle of about 45 degrees. , characterized in that the magnetic thin strip is formed by laminating both of the thin films to form a conductive thin strip that is longer than the width of the magnetic thin strip, and then simultaneously etching the conductive layer and the magnetic layer using the same pattern as a mask. This is achieved by providing a method for manufacturing a magnetic detector.

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

The present invention uses a conductive thin strip (
The length is made longer than the magnetic thin strip (width W) (W<Z), and both thin films are sequentially etched from the upper layer to form a pattern.

Fig. 3 (A), , '(E) cross-sectional view and the same figure) 1. .

(The embodiment of the present invention is shown in the plan view of Ql, but the plan view (bl
, , .

(0) Corresponds to cross-sectional views (B), , (E). Third
As shown in Figure (A), a magnetic layer (I!!i
i thickness 300-500 people) 12, adhesion layer (II! 1 thickness 25
0-1000 people) 16, conductive layer (thickness 500-2000
(13) are continuously formed into a film. The formation of the axis of easy magnetization is the same as in the conventional case.

Lithography and etching techniques (chemical.

The width of the magnetic layer 12 (W
) (FIG. 3(B)).

At this time, the adhesive layer 16 is also etched at the same time. Next, the magnetic layer 12 is patterned by lithography using a new resist film 18 (FIG. 3 (C1), ff1
Since it is longer than J<W, it is not necessary to perform exact alignment (see FIG. 3(b), fcl). The conductive layer 13 protruding from the magnetic ribbon is etched at the same time as the magnetic ribbon is formed (FIG. 3(D), +d).

Finally, a protective layer 14 such as 5i02 is produced, and a terminal corresponding to the external terminal 5 in FIG. 2 is formed using a conductor such as a sieve (FIGS. 3E and 3E).

According to the present invention, by forming a pattern sequentially from the upper layer using a conductive thin strip longer than W, it is possible to realize an accurate positional relationship between the magnetic layer and the conductive layer through simple alignment. It is possible to prevent a decrease in output efficiency, and the effect is significant.

Note that the materials used for the ribbon, adhesive layer, etc. are not limited to those in the examples.

Further, the width, shape, etc. of the thin strip are not limited to those shown in the drawings, and can also be applied to corner portions of a meandering shape. When using a silicon wafer, it is necessary to provide an insulating film thereon as in the conventional case, but when using a Pyrex substrate, this is not necessary. When etching is done by chemical etching, the substrate 11 is not affected, but
During ion milling, the substrate is also slightly etched.

However, since the substrate is provided as a stand on which the magnetoresistive element is placed, there is no problem with the etching of the substrate.

(7) Effects of the Invention As explained in detail above, according to the present invention, the positional relationship between the magnetic layer and the conductive layer can be realized accurately by self-alignment using the same pattern, thereby reducing the output efficiency. It has the effect of eliminating

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the principle of the present detector, FIG. 2 is a cross-sectional view and a plan view of a conventional example, and FIG. 3 is a diagram showing an embodiment of the present invention. ti--substrate, 12-magnetic layer, 13-conductive layer, 14-protective layer, 15-external terminal, 16-adhesion layer, 17, 18--
Resist film (b) Fig. 1jls 2 i”j Fig. 3

Claims (1)

[Claims] A method of making a magnetic detector in which a conductive layer made of a conductive thin strip is arranged at an angle of about 45 degrees on a magnetic layer made of a magnetic thin strip, and both layers are laminated to have a length longer than the width of the magnetic thin strip. 1. A method of manufacturing a magnetic detector, characterized in that after forming a conductive thin strip, the conductive layer and the magnetic layer are simultaneously etched using the same pattern as a mask to form the magnetic thin strip.