JPH0823129A - Magnetoresistance element and manufacture - Google Patents

Abstract

PURPOSE:To provide a magnetoresistance element that is without a shift of central electric potential, has a small size and with an element that can be arranged near to and in parallel with a magnetic material. CONSTITUTION:A magnetoresistance element comprises an insulating layer 1 made of ceramic or glass, or a compound of the glass and the ceramic, a conductor metallized layer 3 that is formed to connect between the surfaces of the inside and outside at the inside or the outside of the insulating layer 1, a magnetoresistance film 2 of the predetermined shape formed on the insulating layer 1 and a resistor of a predetermined shape formed on the back surface of the insulating layer 1. At the state of saturated magnetic field applied to the magnetoresistance element, the shift of the central electric potential is eliminated by trimming an external resistor material and balancing the compound resistance with the ferromagnetic sensitive part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes a property that an electric resistance value changes when a magnetic field is applied, to detect magnetism and to detect the presence or movement of a magnetic body and its manufacture. It is about the method.

[0002]

2. Description of the Related Art In recent years, in a magnetoresistive effect element capable of obtaining a highly accurate output, as shown in, for example, Japanese Patent Application Laid-Open No. 62-293683 and Japanese Patent Application Laid-Open No. 4-18778, measures against temperature drift and improvement in accuracy of output signal are performed. Is being carried out. Measures against temperature drift means that a series connection of an electric resistance element for position detection and an element for non-position detection is a set of elements,
The potential of the connection point (hereinafter referred to as the midpoint potential) is to be output. Improving the accuracy of the output signal means adding a resistor separately to the element for the deviation of the midpoint potential caused by the nonuniformity of the pattern shape and the magnetic behavior in the element formation, and balancing the combined resistance by trimming the element. .

[0003]

However, in the conventional structure as described above, the resistor forming the combined resistance with the ferromagnetic material magnetic sensitive portion is formed on the same plane as the ferromagnetic material magnetic sensitive portion. ) An extra space is required and the element size becomes large. 2) Since the element that is thicker than the position detecting element is formed on the element surface, there is a problem that the element cannot be placed closest to and parallel to the magnetic body. .

In view of the above problems, the present invention is compact and
The element can be placed close to and parallel to the magnetic body.
The present invention provides a magnetoresistive effect element having no deviation of the midpoint potential and a method for manufacturing the same.

[0005]

In order to achieve the above object, the magnetoresistive effect element of the present invention comprises a ceramic composition or an insulating layer made of glass or a composition of glass and ceramic, and the inside or outside of the insulating layer. A conductor metallization layer formed so as to connect between the front and back surfaces and between the components, a thin film having a magnetoresistive effect of a predetermined shape formed on the insulating layer, and a predetermined shape of a thin film formed on the insulating layer. It is composed of a resistor and its trimming portion.

Further, the manufacturing method of the present invention comprises the steps of producing a green sheet made of ceramic or glass, ceramic raw material powder, a binder and a plasticizer, a step of forming a through hole in the green sheet, and the green sheet. A step of printing and filling a through hole with a conductive paste, a step of printing a resistor paste on the green sheet, a step of printing a glass paste on the green sheet, and printing and filling by the green sheet and each step And the step of forming a thin film having a magnetoresistive effect on the glass glaze surface side of the obtained substrate as a magnetic sensitive portion of a predetermined shape, and trimming the resistor after baking. The step of balancing the combined resistance with the magnetically sensitive portion having the magnetoresistive effect, and taking out the terminal from the conductor on the back surface of the substrate.

[0007]

According to this structure, since the resistor is formed so as to be connected to the element and further trimmed, the combined resistance balance of the element and the resistor can be obtained. Therefore, the shift of the midpoint potential can be eliminated. In addition, since the resistor forming surface and the magnetoresistive thin film surface are on the front and back, the space required for forming the adjusting resistor is not required, and the size can be reduced, and the device surface failure Since there are no objects, the element can be placed close to and parallel to the magnetic body.

[0008]

【Example】

(Embodiment 1) Hereinafter, a magnetoresistive effect element according to a first embodiment of the present invention and a method for manufacturing the same will be described with reference to the drawings. FIG. 1 is a sectional view of a magnetoresistive effect element according to an embodiment of the present invention, FIG. 2 is a top view, and FIG. 3 is a bottom view.

In FIGS. 1, 2 and 3, 1 is an insulating layer,
Reference numeral 2 is a magnetoresistive thin film made of a ferromagnetic material, 3 is a conductor metallization layer, 4 is a resistor, 5 is a current supply terminal (+), 6 is GND, and 7 and 8 are output terminals (intermediate terminals).

The magnetoresistive element according to the first embodiment of the present invention comprises a substrate containing borosilicate glass and alumina as main components, and an insulating layer 1 formed by forming lead borosilicate glass on a substrate containing nickel and iron. , A cobalt containing, as a main component, one or more of, for example, a magnetoresistive thin film 2 formed by folding back a thin stripe made of permalloy. On the opposite surface of the substrate, for example, a ruthenium oxide-based external layer is formed. Resistor 4
Are formed. Inside the insulating layer 1 and on the front and back surfaces, for example, a conductor metallization layer 3 having a silver: palladium ratio of 80:20 is formed by electrically connecting the magnetoresistive thin film 2 and the external resistor 4 in series, In particular, the back electrode part serves as an input / output terminal.

The conductor may be one having a different ratio of silver and palladium, or silver, palladium, or gold.

(Embodiment 2) FIG. 4 shows a top view of a magnetoresistive effect element according to a second embodiment of the present invention, FIG. 5 is a sectional view, and FIG. 6 is a bottom view. Each symbol is the same as that of the first embodiment.

Next, the manufacturing method of the present invention will be described. Borosilicate glass powder and alumina powder in a weight ratio of 60
Mixed as an inorganic component with a ratio of 40, polyvinyl butyral, polyvinyl alcohol, etc. as an organic binder, dibutyl phthalate (DBP) as a plasticizer, and a mixed solution of toluene and ethanol as a solvent (60:40 ratio).
100 parts of an inorganic component, 5 parts of an organic binder, 10 parts of dibutyl phthalate (DBP), and 30 parts of toluene and ethanol are mixed and wet pulverized to form a slurry, and then air bubbles are removed from the slurry by vacuum deaeration treatment. It was removed and the viscosity was adjusted. The slurry was coated on a polyester support using a doctor blade, dried through an oven,
A green sheet having a thickness of 0.3 mm was produced. While removing the green sheet from the support, the through hole is formed by punching to form a through hole. For example, a conductor paste having a silver: palladium ratio of 80:20 is filled in the through hole, and a pattern is formed on the front and back surfaces. After printing and drying, two types of sheets were prepared, one for the front surface (hereinafter referred to as sheet A) and one for the back surface (hereinafter referred to as sheet B). Sheet A
And the sheet B were pressure-bonded at 70 ° C. and 100 kg / cm ² . still,
It does not need to be composed of two or more sheets, and may be one sheet on which a predetermined conductor pattern is formed. Subsequently, the glass paste was printed on the surface side of the sheet in a predetermined pattern and dried. Next, after holding in / out at 900 ° C. for 1 hour, it was taken out at room temperature. After firing, print a paste of ruthenium-based glaze resistance film in an amount of 10 to 100Ω,
Similarly, it was held at 900 ° C. for 1 hour and then taken out at room temperature. Note that the ruthenium-based glaze resistance film may be formed at any time after the green sheet is peeled from the support and before the final firing in the process of completing the substrate. Next, the obtained substrate is placed in a vacuum vapor deposition machine, and after evacuation to a predetermined vacuum degree, permalloy is vapor-deposited to a thickness of 0.1 μm on the substrate surface, resist coating, exposure, development, etching,
After stripping the resist, a magneto-sensitive pattern having a shape in which stripes were folded back with permalloy having a width of 10 μm was obtained.
After dividing the substrate into a predetermined chip size, here 4.5 mm × 3.5 mm, a lead was attached to the back surface electrode. The lead connection method was soldering. Wire bonding, bumps, etc. can also be performed.

Next, 5 V was applied between the current supply terminal (+) and GND of the obtained device, and further, a saturation magnetic field of 200 oersted of the device was applied from the outside in a direction perpendicular to the longitudinal direction of the device. The external resistor 4 was laser-trimmed at the location 4a so that the potential between the output terminal (intermediate terminal) of 8 and GND was 2.5 V and the same.

The applied voltage and the saturation magnetic field are 5 V and 20 as described above.
It is not limited to 0 Oersted.

The magnetoresistive effect element having the above-described structure was compared with the conventional magnetoresistive effect element in the midpoint potential distribution.

The magnetoresistive effect element consisting of only the ferromagnetic thin film of the prior art in which the midpoint potential is not adjusted will be described below. FIG. 7 is a top view thereof.

In FIG. 7, 11 is an insulating substrate, 12 is a ferromagnetic thin film, 13 is a current supply terminal (+), and 14 is GN.
D, 15, 16 are output terminals (intermediate terminals).

The comparison results are shown in (Table 1).

[0020]

[Table 1]

As is clear from Table 1, the magnetoresistive effect element of the present invention has a smaller variation distribution of the midpoint potential than the conventional magnetoresistive effect element.

Further, the element size in the case where an external resistor is connected to the magnetoresistive effect element of the above-mentioned conventional example based on the idea of JP-A-62-293683 and JP-A-4-18778 was obtained.

FIG. 8, FIG. 9 and FIG. 10 show the top, cross-section and bottom views of the device. Reference numerals in the figure are the same as those in FIGS. A comparison was made with the size of the magnetoresistive effect element of the present invention.

The conversion size of the conventional example is 7.5 mm × 4.0 mm
Which is significantly larger than the 4.5 mm × 3.5 mm of the present invention.

As described above, according to the present embodiment, an external resistor is formed at a place other than the element surface (for example, the back surface) so as to be connected to the element, and further trimmed to obtain a combined resistance balance with the element. Therefore, it is impossible to satisfy all of the conventional problems of miniaturization, flattening of the element surface, and elimination of the shift of the midpoint potential. 1) To eliminate the shift of the midpoint potential by resistance adjustment. 2) The surface space required for forming the adjustment resistor is not required, so that the size can be reduced. 3) Since there is no obstacle on the element surface, the element can be placed close to and parallel to the magnetic body. A magnetoresistive effect element satisfying all three points of being able to be installed was realized.

(Example 3) In the magnetoresistive effect element of this example, alumina and glass glaze were used as the insulating layer 1, and platinum was used for the conductor metallized layer 3 inside the insulating layer 1 and on the front and back surfaces.

In producing the magnetoresistive element, the conductor and alumina were fired at 1550 ° C.

Others are the same as those in the first embodiment. Also in this example, the same effect as in Example 1 could be obtained.

Example 4 In the magnetoresistive effect element of this example, a nichrome thin film was used as the external resistor 4.

In the manufacture of the magnetoresistive effect element, a nichrome thin film is formed by forming a metal plate on the insulating layer 1 after forming a substrate, before depositing a permalloy film, or after completion of a magnetically sensitive surface and before trimming. It was formed by vapor-depositing nichrome on the back surface.

Others are the same as those in the first embodiment. Also in this example, the same effect as in Example 1 could be obtained.

(Embodiment 5) In the magnetoresistive effect element of this embodiment, a nickel alloy is used as the external resistor 4.

In the manufacture of the magnetoresistive effect element, the nickel-based alloy was formed by the electroless plating solution containing nickel sulfide and sodium hypophosphite after the substrate was manufactured and before the permalloy film was deposited. As impurities, phosphorus, cobalt, tungsten, aluminum,
Contains chromium, zinc, etc.

Others are the same as those in the first embodiment. Also in this example, the same effect as in Example 1 could be obtained.

[0035]

As described above, according to the present invention, an external resistor is formed at a place other than the element surface (for example, the back surface) so as to be connected to the element, and further trimming thereof forms a combined resistance balance with the element. Since it is a structure to obtain, in contrast to the conventional problem that it is not possible to satisfy all the requirements of downsizing, flattening of the element surface, and elimination of the shift of the midpoint potential, 1) elimination of the shift of the midpoint potential by resistance adjustment 2) The space required for forming the adjusting resistor is not required, so that the size can be reduced. 3) Since there is no obstacle on the element surface, the element can be placed close to and parallel to the magnetic body. A magnetoresistive effect element satisfying all three points can be realized.

[Brief description of drawings]

FIG. 1 is a sectional view of a magnetoresistive effect element according to a first embodiment of the present invention.

FIG. 2 is a top view of the magnetoresistive effect element.

FIG. 3 is a bottom view of the magnetoresistive effect element.

FIG. 4 is a top view of a magnetoresistive effect element according to a second embodiment of the present invention.

FIG. 5 is a sectional view of the magnetoresistive effect element.

FIG. 6 is a bottom view of the magnetoresistive effect element.

FIG. 7 is a top view of a magnetoresistive effect element composed only of a ferromagnetic thin film when the conventional midpoint potential is not adjusted.

FIG. 8 is a top view of a magnetoresistive effect element in the case where an external resistor for adjusting the conventional midpoint potential is connected to the element surface.

FIG. 9 is a sectional view of the magnetoresistive effect element.

FIG. 10 is a bottom view of the magnetoresistive effect element.

[Explanation of symbols]

 1 Insulating layer 2 Magnetoresistive thin film 3 Conductor metallization layer 4 Resistor 4a Trimming part

Claims (4)

[Claims] 1. An insulating layer made of a ceramic composition or glass or a composition of glass and ceramic, and a magnetoresistive thin film having a predetermined shape formed on the insulating layer,
A resistor having a predetermined shape formed on the back surface of the insulating layer and its trimming portion, and inside or outside the insulating layer,
A magnetoresistive effect element comprising a resistor, the magnetoresistive thin film, and a conductor metallization layer formed so as to connect between front and back surfaces of the insulating layer and between components. 2. A step of producing a green sheet made of ceramic or glass, a ceramic raw material powder, a binder, and a plasticizer; a step of forming a through hole in the green sheet; and a step of printing a conductive paste on the green sheet. The step of filling the holes, the step of printing the resistor paste on the green sheet, the step of printing the glass paste for glass glaze on the green sheet, the raw sheet and the material printed and filled by the steps A step of firing at a high temperature, and a step of forming a thin film having a magnetoresistive effect on the glass glaze surface side of the obtained substrate as a magnetic sensitive section of a predetermined shape
And a step of trimming the resistor after firing to balance the combined resistance with the magnetic sensitive portion having a magnetoresistive effect. 3. A step of producing a green sheet made of ceramic or glass, a ceramic raw material powder, a binder, and a plasticizer, a step of forming a through hole in the green sheet, a step of printing a conductive paste on the green sheet, and a through step. The step of filling the holes, the step of printing the glass paste for glass glaze on the raw sheet, the step of firing the raw sheet and the material printed and filled by each step at a high temperature, and the sheet after the firing A step of forming a thick film or thin film resistor on the surface opposite to the glass glaze surface, and a step of forming a thin film having a magnetoresistive effect on the glass glaze surface side of the obtained substrate as a magnetic sensing part of a predetermined shape, A step of trimming the resistor to balance the combined resistance with the magnetically sensitive portion having the magnetoresistive effect. Method. 4. The method of manufacturing a magnetoresistive effect element according to claim 2, wherein the trimming of the resistor is performed with the magnetoresistive effect element being placed in a magnetic field.