JPH08242028A - Magneto-resistance effect element and its manufacture - Google Patents

Abstract

PURPOSE: To contrive an adhesion strength enhancement to a magnetic body by a method wherein a magneto-resistance effect thin-film is formed on a glass glaze layer formed on an insulation layer surface comprising a composition of glass and ceramics and glass. CONSTITUTION: A hard magnetic layer 2 of a ferrite being main elements such as Ba, Sr, Fe and the like is formed on a lower surface of an insulation layer 1 being main components which are borosilicate glass and alumina. A glass glaze layer 3 of a borosilicate system is formed on an upper surface of the insulation layer 1, and a magneto-resistance effect thin-film 4 of a specific shape repeatedly folding back fine stripes comprising elements being main components such as Ni, Co is formed thereon. A conductive metallized layer 5 is formed on front and rear surfaces and the inside of the insulation layer 1 so as to be connected with the thin-film 4. As a hard magnetic body is used as a bias magnetic field, an electric power is unrequired for element driving and density of the magnetic body increases, so that a ferromagnetic field can be obtained. As the insulation body is connected to the magnetic body by glass diffusion in a sintering reaction, adhesion strength between a substrate and the magnetic body increases.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive effect element for detecting magnetism and the presence or movement of a magnetic substance and its manufacture by utilizing the property that the electric resistance value changes when a magnetic field is applied. It is about the method.

[0002]

2. Description of the Related Art Magnetoresistance effect elements include a type in which a magnetoresistance effect thin film is made of permalloy or the like and does not require a bias magnetic field, and a type in which the thin film is made of nickel cobalt or the like and requires a bias magnetic field.

The latter type will be described below. The bias magnetic field is to move the operating point for the purpose of 1) discriminating the polarity of the magnetic field to be measured, and 2) obtaining linearity without hysteresis in the region where the magnetic field change is detected. Is applied.

As a bias applying method, there are old methods such as a current method using a magnetic field from a current line and a magnet method using a permanent magnet, and a new method is, for example, JP-A-57-131078.
As shown in Japanese Patent Laid-Open No. 1-274175,
A method (hereinafter referred to as a magnet powder resin method) of applying and fixing a dispersion of hard magnetic powder with a binder such as a resin has been considered.

The magnitude of the output is basically determined by the rate of change in magnetoresistance. The main factor is the material composition, but it is also affected by the pattern structure, the material of the underlying substrate, the construction method, and the like. In order to meet the demand for high output, so-called magnetic field deposition, which is a method of depositing a magnetoresistive thin film in a magnetic field applied state, is often performed technically.
The magnetic field application method includes a current method and a magnet method.
On the other hand, when cost is prioritized over high output, the magnetoresistive thin film is formed by vapor deposition without applying a magnetic field (hereinafter referred to as ordinary vapor deposition).

[0006]

However, in the conventional bias magnetic field structure as described above, there are problems in the current method such as 1) large power consumption and 2) large size. In the magnet method, 1) when the element is bonded with an adhesive, the adhesive strength is small, especially against environmental changes such as thermal shock and humidity resistance. 2) The element operating temperature depends on the heat resistance of the adhesive. There is a problem that the upper limit of 3 becomes low, and 3) when fixed by a mechanical method, the size of the connecting portion becomes large. In the magnetic powder resin method,
1) Since the amount of magnet powder is small, a strong magnetic field cannot be obtained in a small size. 2) There is a problem that the upper limit of the device operating temperature is lowered due to the heat resistance of the resin. Further, in any of the methods, there is a problem in that it requires a step of attaching the magnetic field after separating the pieces into pieces, which causes a problem of cost increase.

Further, in the structure of the conventional manufacturing method for increasing the output as described above, since the combination of the vacuum vapor deposition machine and the magnetic field applying device is required, the combined equipment becomes large and complicated. Therefore, 1) the device cost itself becomes expensive,
2) Since the magnetic field application device is placed in the thin film deposition area of the vacuum deposition machine, there is a problem that the deposition space of the product is reduced and the number of products to be taken is reduced, resulting in high cost in exchange for high output. .

The present invention is to solve the above-mentioned conventional problems. Regarding the structure of the bias magnetic field, 1) power is unnecessary for driving the element, 2) size is small, 3) element and bias magnetic field It is an object of the present invention to provide a magnetoresistive effect element and a method for manufacturing the same, which have high adhesive strength, 4) high upper limit of element operating temperature, 5) high magnetic field, and 6) low cost.

Further, regarding the structure of the manufacturing method for high output, it is an object to provide a magnetoresistive effect element and a manufacturing method thereof which satisfy 1) low cost and 2) large rate of change in magnetoresistance. To do.

[0010]

In order to achieve the above object, a magnetoresistive effect element of the present invention is formed by an insulating layer made of glass and a ceramic composition and glass, and the surface of the insulating layer. A glass glaze layer and a magnetoresistive thin film of a predetermined shape formed on the glass glaze layer,
A hard magnetic layer formed in contact with the other surface of the insulating layer, and a conductor metallized layer connected to the magnetoresistive thin film on the insulating layer.

The method of manufacturing a magnetoresistive effect element having a bias magnetic field of the present invention comprises a step of preparing a green sheet for an insulating layer containing glass and ceramic raw material powders as main components, and hard magnetic powders as main components. And a step of laminating the two types of green sheets, and a conductive paste and a glass paste for glass glaze on the green sheet for the insulating layer of the laminated green sheets. Steps of printing and drying, steps of baking at a high temperature, steps of forming a magnetoresistive thin film on the glass glaze side of the obtained substrate as a magnetically sensitive portion of a predetermined shape, and steps of dividing this substrate into individual pieces. And a step of holding this individual piece in a magnetic field.

Further, the method of manufacturing a magnetoresistive effect element having a high output of the present invention comprises a step of preparing a green sheet for an insulating layer containing glass and ceramic raw material powders as main components, and hard magnetic powders as main components. And a step of laminating the two types of green sheets, and a conductive paste and a glass paste for glass glaze on the green sheet for the insulating layer of the laminated green sheets. The steps of printing and drying, the step of baking in a high temperature and magnetic field, the step of forming a magnetoresistive thin film as a magnetic sensitive part of a predetermined shape on the glass glaze side of the obtained substrate, and this substrate into individual pieces And a step of dividing.

[0013]

According to the structure of the magnetoresistive effect element having the bias magnetic field and the method of manufacturing the same according to the present invention, 1) the hard magnetic material is used as the bias magnetic field, so that electric power is unnecessary for driving the element. 2) Due to the manufacturing method of the bias magnetic material,
A strong magnetic field can be obtained as compared with the magnet powder resin method because a structural difference occurs between the magnetic sintered body and the one in which magnetic powder is present in the binder, that is, the density of the magnetic body increases. 3) Since the insulator and the magnetic body are joined by the glass diffusion in the firing reaction, (1) a separate bonding means / step and a jig for fixing are unnecessary, so that the size and cost can be reduced. (2)
The adhesive strength between the substrate and the magnetic body is increased. (3) Since the adhesive portion is thermally stable at a temperature lower than the glass transition point, the element operating temperature becomes high.

Further, according to the structure of the magnetoresistive effect element having a high output and the manufacturing method thereof, 1) the base substrate replaces the conventional magnetic field applying equipment, and the magnetic field is applied to the ferromagnetic metal during vapor deposition. However, since a thin film is formed, a magnetoresistive thin film with improved spin magnetic orientation is obtained, and the magnetoresistance change rate is increased. 2) No magnetic field application equipment is required in the vapor deposition machine, and the equipment cost is low. 3) Similarly, since the space for the magnetic field applying equipment is not required in the vapor deposition machine, the number of products to be taken per batch is increased and the cost is reduced.

[0015]

【Example】

(Embodiment 1) Hereinafter, a magnetoresistive effect element according to Embodiment 1 of the present invention will be described with reference to the drawings.

1 and 2, a magnetoresistive effect element according to the present embodiment is a ferrite-based element having barium, strontium, iron, etc. as main elements on the lower surface of an insulating layer 1 containing borosilicate glass and alumina as main components. For example, a hard magnetic layer 2 made of barium ferrite is formed, a borosilicate glass glaze layer 3 is formed on the upper surface of the insulating layer 1, and nickel and cobalt as main components are formed on the glass glaze layer 3. A magnetoresistive effect thin film 4 made of at least one kind of element, for example, nickel iron cobalt and having a predetermined shape such as a thin stripe is repeatedly folded is formed. A conductor metallization layer 5 is formed so as to be connected to the magnetoresistive thin film 4, and the conductor metallization layer 5 includes current supply terminals (+) 6 and G.
ND7 and output terminals (intermediate terminals) 8 and 9.

The insulating layer 1 may have a borosilicate glass / alumina ratio of 10:90 to 70:30. 1 glass
If it is less than 0, the adhesive strength between the insulating layer 1 and the hard magnetic layer 2 will be insufficient, and if it is more than 70, the substrate strength will be weak, and neither will be a product.

The glass glaze layer 3 may have a surface roughness Ra of less than 0.20 μm. Surface roughness Ra is 0.2
If it is 0 μm or more, a sufficient magnetoresistance change cannot be obtained.

The conductor metallized layer 5 may be a simple substance such as silver, palladium, gold or the like, or a combination of the above metals, which has a different composition ratio, in addition to the above platinum.

Next, a manufacturing method according to the first embodiment of the present invention will be described. Borosilicate glass powder and alumina powder are blended as an inorganic component, polyvinyl butyral, polyvinyl alcohol, etc. as an organic binder, dibutyl phthalate (DBP) as a plasticizer, a mixed solution of toluene and ethanol as a solvent, and oleic acid as a dispersant. Then, after wet pulverization to make a slurry, bubbles were removed from the slurry by vacuum deaeration treatment, and the viscosity was adjusted. The slurry was coated on a polyester support using a doctor blade and dried through an oven to prepare a 0.3 mm thick green sheet for an insulating layer. In addition, punch in place,
Through holes were formed using a mold (hereinafter referred to as sheet A).

After using barium and iron salts as main starting materials to obtain ultrafine powder by coprecipitation method, hydrothermal synthesis method, etc., 700 to 1
The barium ferrite powder was obtained by firing at 000 ° C. Using this as an inorganic component, wet pulverization was performed together with the organic binder, plasticizer, dispersant, and solvent to obtain a slurry. Bubbles were removed from the slurry and the viscosity was adjusted. The slurry was coated on a polyester support using a doctor blade and dried through a furnace to prepare a 1 mm thick green sheet for a hard magnetic layer of barium ferrite. further,
It was cut into a predetermined shape (hereinafter referred to as sheet B).

Sheet A and sheet B are pasted together at 80 ° C.,
One sheet was obtained by pressing at 200 kg / cm ² (hereinafter,
Sheet C).

On the insulating layer side of the sheet C, a glass paste containing borosilicate glass as an inorganic component is printed in a predetermined pattern and dried, and further, for example, a conductor paste containing platinum as an inorganic component is printed in a predetermined pattern and dried to obtain a sheet. Was baked to obtain a substrate. The firing temperature has a peak temperature of 800 to 13.
It may be 00 ° C. It is changed according to the desired bias amount and substrate strength.

The firing time and number of firings are not limited to the above. For example, after firing the sheet C, the conductor paste and the glass paste may be printed and dried, and then fired again.

The thickness of each green sheet is not fixed as described above. It is changed according to the desired bias amount, size, substrate strength, etc.

The obtained substrate was placed in a vacuum vapor deposition machine, evacuated to a predetermined vacuum degree, nickel iron cobalt was vapor-deposited to a thickness of 0.1 μm on the substrate surface, and resist coating, exposure, development, etching, After stripping the resist, a magneto-sensitive pattern having a shape in which the stripe was folded back with nickel iron cobalt having a width of 10 μm was obtained. After dividing the substrate into a predetermined chip size, the chip was set in a magnetizer, and a strong magnetic field was applied to magnetize the chip.

Regarding the magnetoresistive effect element having the above-mentioned structure, the conventional magnetoresistive effect element is compared, and the adhesive strength between the insulating layer and the hard magnetic layer is the number of peels after the reliability test of our standard, The element use limit temperature and the bias amount were evaluated. In the conventional example, a magnet system (a permanent magnet and a substrate fixed with an adhesive) and a magnet powder resin system were used.

The results are shown in (Table 1).

[0029]

[Table 1]

As is clear from Table 1, the magnetoresistive effect element of the present invention is superior to the magnetoresistive effect element of the conventional example in the adhesive strength between the insulating layer and the hard magnetic layer, the element use limit temperature, and the bias amount. It turns out that it is equal to or more than equal.

As described above, according to this embodiment, 1) no electric power is required for applying a bias magnetic field, 2) a strong magnetic field can be obtained, 3) small size, and 4) adhesion between the element and the bias magnetic field. 5) High strength, 5) High element usage limit temperature,
6) A magnetoresistive effect element and a manufacturing method thereof satisfying low cost can be realized.

(Second Embodiment) A magnetoresistive effect element according to a second embodiment of the present invention will be described below with reference to the drawings.

Referring to FIGS. 3 and 4, the magnetoresistive effect element according to the present embodiment is a ferrite-based element having barium, strontium, iron, etc. as main elements on the lower surface of the insulating layer 1 containing borosilicate glass and alumina as main components. , The hard magnetic layer 2 made of barium ferrite is formed, and the insulating layer 1 is formed on the lower surface of the hard magnetic layer 2 as well.
Are formed so as to sandwich. Then, a borosilicate glass glaze layer 3 is formed on the insulating layer 1, and two or more elements containing nickel and cobalt as main components are formed on the glass glaze layer 3, for example, nickel cobalt. The magnetoresistive effect thin film 4 having a predetermined shape is formed by repeatedly folding a thin stripe, and the insulating layer 1 is formed.
On the surface of, for example, a silver: palladium ratio of 80: 2.
A conductor metallization layer 5 of 0 is formed by connecting to the magnetoresistive thin film 4, and the conductor metallization layer 5 is a current supply terminal (+).
6, GND 7, and output terminals (intermediate terminals) 8 and 9.

The insulating layer 1 may have a borosilicate glass / alumina ratio of 10:90 to 70:30.

The glass glaze layer 3 may have a surface roughness Ra of less than 0.20 μm. Conductor metallization layer 5
In addition to the above glass having a ratio of silver to palladium of 80:20, the glass may have different composition ratios, such as silver, palladium and gold.

In the method of manufacturing the magnetoresistive effect element, the step of adhering the insulating layer sheet A and the hard magnetic layer sheet B in Example 1 is performed by sandwiching the sheet B with the sheet A. The process.

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

(Embodiment 3) Hereinafter, in the method of manufacturing a magnetoresistive effect element according to Embodiment 3 of the present invention, the step of producing a green sheet containing barium ferrite magnetic powder as a main component is performed using the magnetic powder as a main component. The paste was printed.

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 4) A method of manufacturing a magnetoresistive effect element according to Embodiment 4 of the present invention will be described below.

Borosilicate glass powder and alumina powder are mixed as an inorganic component, polyvinyl butyral, polyvinyl alcohol, etc. as an organic binder, dibutyl phthalate (DBP) as a plasticizer, a mixed solution of toluene and ethanol as a solvent, and olein as a dispersant. After mixing the acid and performing wet pulverization to make a slurry, bubbles were removed from the slurry by vacuum deaeration treatment to adjust the viscosity. The slurry was applied onto a polyester support using a doctor blade and dried through a furnace to prepare a 0.2 mm thick green sheet for an insulating layer (hereinafter referred to as sheet D).

After obtaining ultrafine particle powder by a coprecipitation method, a hydrothermal synthesis method or the like using strontium and iron salts as main starting materials, 8
Firing was performed at 00 to 1100 ° C to obtain strontium ferrite powder. Using this as an inorganic component, wet pulverization was performed together with the organic binder, plasticizer, dispersant, and solvent to obtain a slurry. Bubbles were removed from the slurry and the viscosity was adjusted. The slurry was applied onto a polyester support using a doctor blade and dried through a furnace to prepare a raw sheet for a hard magnetic layer of strontium ferrite having a thickness of 2 mm (hereinafter referred to as sheet E).

The step of producing a green sheet containing strontium ferrite magnetic powder as a main component may be a step of printing a paste containing the magnetic powder as a main component.

The sheet D and the sheet E were sandwiched and laminated, and pressure-bonded at 80 ° C. and 200 kg / cm ² to obtain one sheet (hereinafter referred to as sheet F).

Next, the sheet F was fired while applying a magnetic field. The firing temperature has a peak temperature of 1000 to 140.
It may be 0 ° C.

Subsequently, a glass paste containing borosilicate glass as an inorganic component is printed in a predetermined pattern on the surface side of the substrate and dried, and further, for example, the silver: palladium ratio is 80 :.
The conductor paste of 20 was printed in a predetermined pattern, dried, and fired again. The firing temperature may be 800 to 1000 ° C.

The thickness of each green sheet is not fixed as described above. It is changed according to the desired bias amount, size, substrate strength, etc.

The obtained substrate was placed in a vacuum vapor deposition machine, and after evacuation to a predetermined degree of vacuum, nickel cobalt was vapor-deposited to a thickness of 0.1 μm on the substrate surface, resist coating, exposure, development, etching, resist After peeling, a magneto-sensitive pattern having a shape in which a stripe was folded back with nickel cobalt having a width of 10 μm was obtained. The substrate was divided into a predetermined chip size.

With respect to the magnetoresistive effect element having the above structure, the magnetoresistive effect element of the conventional example was compared with the magnetoresistive change rate. The conventional magnetoresistive effect element is obtained by ordinary vapor deposition. That is, the manufacturing costs were made equal.

The comparison results are shown in (Table 2).

[0051]

[Table 2]

As is clear from Table 2, the magnetoresistive effect element of the present invention is superior to the magnetoresistive effect element of the conventional example in the rate of change in magnetoresistance.

As described above, according to this embodiment, a magnetoresistive effect element having a large rate of change in magnetoresistance due to improvement in magnetic orientation can be realized at low cost without using a vapor deposition facility in a magnetic field.

[0054]

As is apparent from the above description, according to the magnetoresistive effect element and the method of manufacturing the same of the present invention, regarding the constitution of the bias magnetic field, 1) no power is required for driving the element, and 2) size. Is small, 3) the adhesion strength between the element and the bias magnetic field is large, 4) the upper limit of the operating temperature of the element is high, 5) a strong magnetic field is obtained, and 6) the cost is satisfied, and the magnetoresistive effect element A manufacturing method can be realized.

Regarding the structure of the manufacturing method for high output, a magnetoresistive effect element and a manufacturing method thereof satisfying 1) low cost and 2) large rate of change in magnetoresistance 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 sectional view of a magnetoresistive effect element according to Example 2 of the present invention.

FIG. 4 is a top view of the magnetoresistive effect element.

[Explanation of symbols]

 1 Insulating Layer 2 Hard Magnetic Layer 3 Glass Glaze Layer 4 Magnetoresistive Thin Film 5 Conductor Metallization Layer

Claims (8)

[Claims] 1. A glass / ceramic composition and an insulating layer made of glass, a glass glaze layer formed on the upper surface of the insulating layer, and a magnetoresistive thin film having a predetermined shape formed on the glass glaze layer. And a hard magnetic layer formed in contact with the lower surface of the insulating layer, and a conductor metallized layer connected to the magnetoresistive thin film on the insulating layer. 2. The magnetoresistive effect element according to claim 1, wherein the hard magnetic layer is sandwiched between insulating layers. 3. A step of producing a raw sheet for an insulating layer containing glass and ceramic raw material powder as a main component, a step of producing a raw sheet for a hard magnetic layer containing hard magnetic powder as a main component, and The process of pasting two kinds of raw sheets together,
A step of printing and drying a conductive paste and a glass paste for glass glaze on a green sheet for an insulating layer of the laminated green sheet, a step of firing at a high temperature, and a magnetoresistive effect on the glass glaze side of the obtained substrate. A method of manufacturing a magnetoresistive effect element, comprising: a step of forming a thin film as a magnetically sensitive portion having a predetermined shape; a step of dividing the substrate into pieces; and a step of holding the pieces in a magnetic field. 4. The step of laminating two kinds of green sheets is a raw sheet for a hard magnetic layer containing hard magnetic powder as a main component, and a raw sheet for an insulating layer containing raw material powders of glass and ceramic as a main component. The method of manufacturing a magnetoresistive effect element according to claim 3, which is a step of sandwiching and pasting. 5. The magnetoresistive element according to claim 3, wherein the step of producing a green sheet for a hard magnetic layer containing hard magnetic powder as a main component is a step of printing a paste containing hard magnetic powder as a main component. Manufacturing method. 6. A step of producing a green sheet for an insulating layer containing glass and ceramic raw material powder as a main component, a step of producing a raw sheet for a hard magnetic layer containing a hard magnetic powder as a main ingredient, The process of pasting two kinds of raw sheets together,
A step of printing and drying a conductive paste and a glass paste for glass glaze on a green sheet for an insulating layer of the laminated green sheet, a step of firing in a high temperature and magnetic field, and a glass glaze surface side of the obtained substrate. 1. A method of manufacturing a magnetoresistive effect element, comprising: a step of forming a magnetoresistive effect thin film as a magnetic sensitive part having a predetermined shape; and a step of dividing this substrate into individual pieces. 7. A raw sheet for a hard magnetic layer containing hard magnetic powder as a main component and a raw sheet for an insulating layer containing glass and ceramic raw material powder as a main component in the step of laminating two kinds of raw sheets. 7. The method for manufacturing a magnetoresistive effect element according to claim 6, which is a step of sandwiching and pasting. 8. The magnetoresistive effect element according to claim 6, wherein the step of producing a raw sheet for a hard magnetic layer containing hard magnetic powder as a main component is a step of printing a paste containing hard magnetic powder as a main component. Manufacturing method.