JPH04179290A - Magnetic sensor - Google Patents

Abstract

PURPOSE:To make the size of a sensor smaller and to reduce the production cost of the sensor by giving a line glazed treatment to an insulation substrate such as ceramic, giving right angle or a predetermined tilt with the line glazed direction and arranging a sensor pattern for magnetic field detection. CONSTITUTION:After giving a line glazed treatment on an insulation substrate such as alumina substrate, a sensor pattern 63 for detecting magnetic field and an electrode 62 made of an Ni alloy magnetic film are formed on the line glazed 61. Also, respective sensor patterns 63 are so arranged in parallel that the magnetic sensor is positioned almost at the center of the line glazed 61 and almost at right angle with the line direction of the line glazed 61. By doing this, when forming the sensor patterns by a photolithographic technique, the distance from a photomask becomes uniform within a sensor pattern, so that each pattern width is uniformly patterned and the impedance of each pattern within a sensor becomes uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic sensor using a magnetoresistive element or a Hall element in a sensor portion.

[Conventional technology]

A magnetic sensor is known in which a glazed portion is partially provided on the surface of an insulating substrate made of ceramic or the like, and a sensor portion made of a Ni alloy magnetic thin film is formed on the glazed portion by photolithography or the like (for example, Unexamined Japanese Patent Publication 1986-
34.987 etc.).

In the above publication, as shown in FIGS. 7(a) and 7(b), a terminal 8 in which a glazed portion 82 is partially provided on an alumina base 81 and a conductive paste is printed and fired on the surface of the alumina base.
3, and a magnetic field detection section 8 is provided in the glazed section 82.
A magnetic sensor is disclosed which is characterized by having a magnetic field detection part 84 and an electrode, and each terminal being separated by a glazed part, and in which the magnetic field detection part 84 and the electrode are made of the same material, Even if etched at the same time, there will be no short circuit between the terminals, which has the advantage that the manufacturing process can be greatly simplified.

[Problem to be solved by the invention]

By the way, since the ceramic substrate, which is an insulating substrate, has poor surface roughness, in order to form a sensor section made of a Ni alloy magnetic thin film, etc., the substrate surface must be subjected to glazing treatment (the surface is covered with a glass layer) as in the above-mentioned conventional technology. process).

In other words, the elements required for this glazed treatment as a substrate surface for a thin film sensor are a) improvement of surface roughness, b)
The two are surface flatness.

Regarding the surface roughness of a, the thickness of the Ni alloy magnetic thin film is 300 to 1,000 times thinner, so if the surface roughness of the substrate is not good, the sensor circuit consisting of a bridge circuit may break or impedance variations may occur. This is because it becomes bigger.

Regarding the flatness of b, glazed treatment generally
This is a process in which glass paste is applied onto a ceramic substrate to form a desired glazed pattern, but since glass paste is a fluid, when it is applied, the glass paste bulges at the edges of the glazed area, and the bulge increases. Since it is returned toward the center of the pattern and the center of the pattern bulges out, the cross-sectional shape of the glazed portion generally becomes a semi-cylindrical shape. For this reason, in the partially glazed pattern shown in FIG. 7, the glazed center portion forming the sensor body actually becomes hemispherical.

Therefore, when forming a sensor pattern consisting of a bridge circuit such as a magnetoresistive element made of a Ni alloy magnetic thin film using photolithography, as shown in FIG. The distances between the sensor patterns become uneven, which causes the impedance at each pattern part of the sensor pattern to vary.

In addition, in the case of partially glazed, the center of the glazed
As shown in FIG. 8, since it is hemispherical in all directions, such a partially glazed pattern has a disadvantage in terms of sensor characteristics, particularly in that impedance variation in the sensor circuit is likely to occur.

In order to improve the flatness of the center of this partially glazed area, it can be achieved by enlarging the pattern of the partially glazed area, but in this case, the problem of increasing the size of the sensor and increasing the manufacturing cost occurs. arise.

As described above, in the case of the prior art, the flatness of the substrate surface is poor because it is partially glazed. This caused the problem that the impedance of the circuit was likely to vary.

The present invention has been made in view of the above-mentioned circumstances.Compared to conventional partially glazed magnetic sensors, the impedance variation of a magnetic sensor circuit consisting of a bridge circuit is small, and the sensor can be miniaturized and manufacturing costs can be reduced. It is an object of the present invention to provide a magnetic sensor that can also achieve a reduction in .

[Means to solve the problem]

In order to achieve the above object, the magnetic sensor of the present invention provides a line glazed pattern by subjecting an insulating substrate to a line glazed process, and a line glazed pattern is formed on the line glazed at approximately right angles to the line glazed direction or at a predetermined direction. It is characterized in that the sensor pattern portions for magnetic field detection are arranged so that the sensor patterns are arranged side by side with an inclination.

[For production]

The disadvantage of the prior art described above is the problem caused by partial glazing, but glazing is necessary when using insulating substrates such as ceramic.

Therefore, in the present invention, a line glazed pattern is used as described above.

Line glazing refers to forming a glazed pattern in a line shape on a substrate. Figure 1 shows its outline. Also, in Fig. 2 (a) and (b), the x of the glazed part is
-x' force direction line direction) and YY' direction (line perpendicular direction) are shown.

In Figures 1 and 2, 1 is an insulating substrate made of alumina, etc., 2 is a line glazed pattern, and x in the figure is
-x' force direction Since the length of the glazed pattern is sufficiently long compared to the pattern of one sensor, the flatness is greatly improved compared to the partially glazed pattern. Further, if the length in the Y-Y' force direction is equal to or about one time that of the partially glazed, the flatness is about the same as that of the partially glazed.

Therefore, by forming a sensor pattern section for magnetic field detection on the line glazed so that each sensor pattern is juxtaposed at right angles to the line glazed direction or at a predetermined inclination, as shown in FIG. To,
Since the patterns R1 to R4 can be arranged so that the distance from the photomask to the surface of the line glazed portion is uniform, it is possible to form a sensor with little variation in impedance between the sensor patterns.

Further, by using the line glazed sensor 2, the sensor can be made smaller than the partially glazed sensor. That is, in partial glazing, as described above, it is necessary to increase the area of one glazed pattern in order to flatten the center of the glazed portion. On the other hand, since line glazed has good flatness in the line direction, there is no need to take dead space for flattening as is the case with partial glazed, so sensor patterns can be formed close to each other on one line glazed. For this reason, line glazed is more suitable for downsizing the sensor.

Furthermore, even when the thickness of the glazed part is increased, by arranging the sensor pattern part for magnetic field detection so that each sensor pattern is juxtaposed at approximately right angles to the line glazed direction or with a predetermined inclination, The variation in sensor impedance can be reduced for partial glazes of the same thickness.

〔Example〕

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

FIG. 4 is a diagram showing an embodiment of the present invention, in which line glazing treatment is performed on an a-edge substrate such as an alumina substrate in the same manner as shown in FIG. FIG. 3 is an enlarged view of a magnetic sensor in which a sensor pattern 63 for detecting a magnetic field and an electrode 62 for outputting a signal are formed of a Ni alloy magnetic thin film or the like.

In this magnetic sensor, each sensor pattern 63 is formed approximately at the center of the line glazed 61 so as to be juxtaposed at substantially right angles to the line direction of the line glazed 61. By arranging the orientation of each sensor pattern 63 in this way, when forming a sensor pattern part using photolithography technology, the distance from the photomask can be adjusted within one sensor pattern part, as shown in FIG. Therefore, each pattern width can be arranged uniformly, so that the impedance of each pattern in the sensor becomes uniform.

Next, FIG. 5 is a diagram showing an example of the pattern arrangement of the sensor section for line glazed, and in the same figure,
Reference numeral 64 is a line glaze, 65 is a sensor pattern section, and 66 is an electrode.

As can be easily inferred from the figure, there are no performance problems whether the electrodes 66 are taken out in the same direction as shown in the figure or in different directions relative to the line glazed 64. do not have.

Next, FIG. 6 is a diagram showing another example of the pattern arrangement of the sensor part with respect to the line glazed, in which reference numeral 67 is the line glazed, 68 is the sensor pattern, and 69 is the electrode.

In this embodiment, flatness in the width direction is improved by increasing the width of the line glazed portion 67, so a plurality of sensor portions can be formed on one line glazed portion 67 in the arrangement shown in the figure. It becomes easily possible to form a plurality of magnetic sensors at the same time.

Next, FIG. 9 is a diagram showing another embodiment of the present invention,
After performing line glazing treatment on an insulating substrate such as an alumina substrate in the same manner as shown in FIG. FIG. 2 is an enlarged view of a magnetic sensor formed with electrodes 92 of FIG.

In the embodiment shown in FIG. 9, the sensor patterns 93 are arranged side by side at a predetermined inclination with respect to the center line (X-X') of the line glazed 91 direction. Since the sensor patterns 93 are arranged side by side in the line glazed direction, similar to the embodiment shown in FIG.
It is possible to configure a magnetic sensor with less variation in impedance between the sensor patterns 93 of the sensor consisting of a bridge circuit.

Further, the magnetic sensor having the configuration shown in FIG. 9 can also be used in the sensor pattern portion shown in FIGS. 5 and 6 similarly to the magnetic sensor shown in FIG. 4.

In each of the above embodiments, a magnetic sensor in which a magnetoresistive element made of a Ni alloy magnetic thin film or the like is used in the sensor section for detecting a magnetic field has been described, but the present invention relates to a magnetic sensor in which a Hall element is used in the sensor section. can be similarly applied.

〔Effect of the invention〕

As described above, in the magnetic sensor of the present invention, by performing line glazing treatment on an insulating substrate such as ceramic, it is possible to improve the flatness in the line glazing direction compared to conventional partial glazing. In addition, by arranging the sensor patterns for magnetic field detection so that each sensor pattern is juxtaposed at right angles to the line glazed direction or at a predetermined inclination, the distance from the photomask can be reduced within a single sensor pattern. Since the sensor pattern is uniform, the thickness of the sensor pattern can be made uniform, and a sensor with less variation in impedance can be formed.

Furthermore, since the flatness in the line glazed direction is good, the sensor can be formed close to that direction, so the sensor can be made smaller compared to the conventional partial glazed.

Further, according to the present invention, since a plurality of sensor parts can be formed simultaneously on one line grade, it is possible to easily mass-produce magnetic sensors and reduce manufacturing costs.

[Brief explanation of the drawing]

Figure 1 is a plan view showing an example of forming a line glazed pattern, Figures 2 (a) and (b) are the x-x' force direction (line direction) and y-y'' direction of the line glazed part shown in Figure 1. 3 is a diagram showing the arrangement of a mask when a sensor pattern is formed on a line glazed part by photolithography technology, and FIG. 4 is a cross-sectional view of a magnetic sensor showing an embodiment of the present invention. An enlarged view of the main parts, FIG. 5 is a diagram showing one example of the pattern arrangement of the sensor part for line glazed, FIG. 6 is a diagram showing another example of the pattern arrangement of the sensor part for line glazed, and FIG. a
), (b) are a plan view and a side view of a conventional magnetic sensor, and FIG. 8 shows the arrangement of a mask when a sensor pattern is formed on a conventional partially glazed part by photolithography technology. FIG. 9 is an enlarged view of a main part of a magnetic sensor showing another embodiment of the present invention. 1... Insulating substrate, 2.61.64.67, 91.
... Line glazed part, 63.65.68.93.
...sensor pattern, 62.66, 69.92...
·electrode. 1. , -1

Claims (1)

[Claims] A line glazed pattern is provided by performing a line glazed process on an insulating substrate, and a magnetic field is applied on the line glazed so that each sensor pattern is arranged in parallel at a substantially right angle or at a predetermined inclination to the line glazed direction. A magnetic sensor comprising a sensor pattern section for detection.