JP2000100601A - Chip resistor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a low TCR and low resistance value by paste-printing a resistance paste contg. a Cu-Ni alloy powder on a recess formed into a ceramic base and baking it in a neutral atmosphere. SOLUTION: Resistance layers 3 are printed on both sides of a square substrate 1 by a thick film forming method such as screen printing, etc., using a resistance paste. Top face electrode layers 2 are printed on a pair of opposed end faces of the substrate 1 so as to contact the resistance layers 3 plane to plane by the same material as the resistance layers 3, the resistance layers 3 and top face electrode layers 2 are baked at once in a neutral or reductive atmosphere. U-shaped end face electrode layers 4 are formed on both ends of the substrate 1. The resistance paste uses a mixture of a Cu-Ni alloy powder with a glass powder and a vehicle in which the mixture is dispersed. A terminal electrode paste uses a high-conductivity material such as commercially available metal Cu or metal Ni, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip resistor using a resistor paste.

[0002]

2. Description of the Related Art Conventionally, a resistor using a copper-nickel material has been realized by a method in which a copper-nickel alloy foil is attached to a substrate such as alumina. However, the resistors manufactured by this method require the cost of alloy foil production, shape processing, assembly, material and process steps, and it takes much time and effort to change the pattern of the resistor. Furthermore, since trimming using a laser cannot be performed, a conventionally established trimming line cannot be used.

[0003]

On the other hand, a technique for producing a resistor by printing and baking a resistor paste on a substrate is disclosed in Japanese Patent Application Laid-Open No. 2-308501. Glass is used for adhesion and resistance adjustment of the ceramic base material and contains a large amount of components other than copper and nickel, so that the temperature coefficient differs from the physical properties of the copper-nickel alloy, Since the diffusion behavior of the components in the metal components and the interface of the sintered particles differs depending on the firing conditions, stable resistance value characteristics were hardly obtained.

A resistor using a copper-nickel material is one of the following.
Since the resistance value range of 00 mΩ or less is handled, the characteristics of the terminal electrode of the power supply unit and the structure of the resistor / electrode interface greatly affect the characteristics of the resistor. In the ultra-low resistance value range of 10 mΩ or less, the resistance film is used. There was a problem that the thickness had to be formed on the order of tens to hundreds of μm.

A main object of the present invention is to stably manufacture a chip resistor having a low TCR and a low resistance value.

[0006]

According to the present invention, a copper-nickel alloy powder alone or a mixed powder containing a copper-nickel alloy powder and a glass powder dispersed in a vehicle is used as a resistor paste. After printing in the recesses on the ceramic substrate provided with the recesses, the chip resistor is manufactured by firing in a neutral atmosphere to minimize the diffusion of the glass component into the metal component, thereby achieving a low TCR,
It is intended to realize a chip resistor having a low resistance value.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is characterized in that the content of copper-nickel alloy powder is more than 97% by weight in a concave portion of a ceramic substrate having a concave portion on one side and is 550 ° C.
A resistor paste in which a mixed powder containing a glass powder having a softening point of less than 0 to less than 3% by weight is dispersed in a vehicle is completely printed, and high-conductivity such as commercially available metallic copper or metallic nickel is applied to both ends thereof. By printing on the concave portion with a chip resistor obtained by connecting with a metal paste having the following and firing in a neutral atmosphere, the resistor does not peel off from the ceramic base even if the glass content is small. In addition, since the diffusion of the glass component into the metal component and the interface with the sintered particles can be suppressed to a minimum, the obtained resistor can have a low TCR, and the thicker resistor film can be obtained by increasing the depth of the concave portion. This has the effect of lowering the resistance value and enabling laser trimming.

According to a second aspect of the present invention, a glass powder having a softening point of more than 97% by weight of copper-nickel alloy powder and less than 550 ° C. in a concave portion of a ceramic substrate having concave portions on both surfaces is reduced to 0 to 3%. A resistor paste in which a mixed powder containing less than 5% by weight is dispersed in a vehicle is completely printed and connected to both ends with a metal paste having a high conductivity such as commercially available metallic copper or metallic nickel to form electrodes on both sides. By printing in the recesses with a chip resistor obtained by connecting with the same paste and firing in a neutral atmosphere, the resistor does not peel off from the ceramic base even if the glass content is small.
In addition, since the diffusion of the glass component into the metal component and the interface to the sintered particle interface can be suppressed to a minimum, the resistor obtained can have a low TCR, and a thicker resistor film can be obtained by increasing the depth of the concave portion. Accordingly, the resistance value can be reduced and the laser can be trimmed. By providing the power supply portion on both sides, the heat resistance is improved.

A third aspect of the present invention is a glass powder having a copper-nickel alloy powder content of more than 97% by weight and a softening point of less than 550 ° C. in a concave portion of a ceramic substrate having a concave portion having a step on one surface. Of a mixed powder containing 0 to less than 3% by weight is dispersed in a vehicle and printed with a resistor paste, and connected to both ends with a commercially available metal paste having a high conductivity such as copper or nickel. By printing in a recess having a step with a chip resistor obtained by firing in a neutral atmosphere, the resistor does not peel off from the ceramic base even if the glass content is small. In addition, since the diffusion of the glass component into the metal component and the interface to the sintered particle interface can be suppressed to a minimum, the TCR of the obtained resistor can be reduced,
Further, by increasing the depth of the concave portion to form a thick resistor film, the resistance value can be reduced and laser trimming can be performed. By providing a step in the concave portion, the step with the electrode joint due to sintering of the resistor is reduced, and the electrode is less likely to break.

According to a fourth aspect of the present invention, there is provided a glass powder having a copper-nickel alloy powder content of more than 97% by weight and a softening point of less than 550 ° C. in a concave portion of a ceramic substrate having a concave portion having a step on both surfaces. Is printed on a resistor paste obtained by dispersing a mixed powder containing less than 0 to 3% by weight in a vehicle, and connected to both ends with a commercially available metal paste having high conductivity such as copper metal or nickel metal. By connecting the electrodes on both sides with the same paste and printing in a recess with a step with a chip resistor obtained by firing in a neutral atmosphere, the resistor can be peeled from the ceramic base even if the glass content is small. Absent. In addition, since the diffusion of the glass component into the metal component and the interface with the sintered particles can be suppressed to a minimum, the obtained resistor can have a low TCR, and the thicker resistor film can be obtained by increasing the depth of the concave portion. Accordingly, the resistance value can be reduced and the laser can be trimmed. By providing the power supply portion on both sides, the heat resistance is improved. By providing a step in the concave portion, the step with the electrode joint due to sintering of the resistor is reduced, and the electrode is less likely to break.

According to a fifth aspect of the present invention, the content of the copper-nickel alloy powder is 9% in the concave portion of the ceramic substrate having the concave portion in which at least the electrode / resistor connection side has no step on one side.
A resistor paste in which a mixed powder containing a glass powder having a softening point of more than 7% by weight and less than 550 ° C and less than 0 to 3% by weight is dispersed and printed in a vehicle, and commercially available metallic copper is coated on both ends thereof A chip resistor obtained by connecting with a metal paste having a high conductivity such as nickel or metal nickel and firing in a neutral atmosphere is printed in a recess with no step, so that even if the glass content is small, the resistor can be Does not peel off from the ceramic substrate. In addition, since the diffusion of the glass component into the metal component and the interface with the sintered particles can be suppressed to a minimum, the obtained resistor can have a low TCR, and the thicker resistor film can be obtained by increasing the depth of the concave portion. This has the effect of lowering the resistance value and enabling laser trimming. Since no step is provided in the concave portion, the step with the electrode joining portion due to sintering of the resistor is eliminated, and the electrode is not cut.

According to a sixth aspect of the present invention, the content of the copper-nickel alloy powder is more than 97% by weight in the concave portion of the ceramic substrate having the concave portion without the step at least the electrode / resistor connection side on both surfaces. In many cases, a resistor paste in which a mixed powder containing a glass powder having a softening point of less than 550 ° C. less than 0 to 3% by weight is dispersed in a vehicle is printed and printed, and commercially available metal copper, metal nickel, etc. The glass content is low by connecting the electrodes on both sides with the same paste, connecting the electrodes on both sides with the same paste, and firing in a neutral atmosphere and printing in a recess without steps with a chip resistor. However, the resistor does not peel off from the ceramic substrate. In addition, since the diffusion of the glass component into the metal component and the interface with the sintered particles can be suppressed to a minimum, the obtained resistor can have a low TCR, and the thicker resistor film can be obtained by increasing the depth of the concave portion. Accordingly, the resistance value can be reduced and the laser can be trimmed. By providing the power supply portion on both sides, the heat resistance is improved. Since no step is provided in the concave portion, the step with the electrode joining portion due to the sintering of the resistor is eliminated, and the electrode is not cut off.

According to a seventh aspect of the present invention, the content of the copper-nickel alloy powder is more than 97% by weight and 550 ° C. in the concave portion of the ceramic base having the concave portion having the concave and convex bottom surface on one side.
A resistor paste in which a mixed powder containing a glass powder having a softening point of less than 0 to less than 3% by weight is dispersed in a vehicle is completely printed, and high-conductivity such as commercially available metallic copper or metallic nickel is applied to both ends thereof. The resistor is peeled from the ceramic base even if the glass content is small by printing on the concave part with the bottom surface uneven by a chip resistor obtained by connecting with a metal paste having It adheres firmly without any. In addition, since the diffusion of the glass component into the metal component and the interface with the sintered particles can be suppressed to a minimum, the obtained resistor can have a low TCR, and the thicker resistor film can be obtained by increasing the depth of the concave portion. This has the effect of lowering the resistance value and enabling laser trimming.

According to the present invention, the content of the copper-nickel alloy powder is more than 97% by weight and 550 ° C. in the concave portion of the ceramic base having concave portions with uneven bottom surfaces on both surfaces.
A resistor paste in which a mixed powder containing a glass powder having a softening point of less than 0 to less than 3% by weight is dispersed in a vehicle is completely printed, and high-conductivity such as commercially available metallic copper or metallic nickel is applied to both ends thereof. Even if the glass content is low by printing on the concave part with the bottom surface uneven by a chip resistor obtained by connecting with a metal paste having the same and connecting the electrodes on both sides with the same paste and firing in a neutral atmosphere The resistor adheres firmly without peeling from the ceramic substrate.
In addition, since the diffusion of the glass component into the metal component and the interface with the sintered particles can be suppressed to a minimum, the obtained resistor can have a low TCR, and the thicker resistor film can be obtained by increasing the depth of the concave portion. Accordingly, the resistance value can be reduced and the laser can be trimmed. By providing the power supply portion on both sides, the heat resistance is improved.

According to a ninth aspect of the present invention, there is provided a resistor which masks both ends of a concave portion of a ceramic base having a concave portion with a resin to leave a concave portion only at a central portion, and contains an alloy powder containing at least copper-nickel therein. After printing and drying the paste and removing the masking, commercially available metal copper or metal nickel paste is printed as an electrode in the recess, dried and fired in a neutral atmosphere, and the resistor and electrode are metal-bonded. A chip resistor obtained by taking out from the substrate as a metal plate, connecting the resistor and the electrode to the concave shape of the substrate,
It can be controlled by the masking shape. Therefore, the resistance value and the TCR characteristic of the obtained resistor can be easily adjusted. The obtained resistor film is less likely to reflect laser energy than a metal foil or a plating film, and thus has an effect capable of laser trimming.

According to a tenth aspect of the present invention, a mixed powder containing a glass powder having a copper-nickel alloy powder content of more than 97% by weight and a softening point of less than 550 ° C of less than 0 to 3% by weight is provided as a vehicle. After the resistor paste dispersed in the recesses on one side of the ceramic substrate is completely printed and dried,
A commercially available metal copper paste is printed and dried on both ends as a lower electrode, and then a metal nickel paste is printed and dried on the lower electrode as an upper electrode and baked in a neutral atmosphere. Detachment from the substrate due to the internal stress of the body film can be mitigated by providing recesses in the substrate, and by making the glass component a few percent, the diffusion of the glass component into the metal component and the interface to the sintered particles can be suppressed to a minimum. The connection between the resistor and the electrode can be controlled by the printing pattern. Therefore, the obtained resistor can have low resistance and low TCR. Further, the obtained resistor film is less likely to reflect laser energy as compared with a metal foil or a plating layer, and thus has an effect capable of laser trimming. Further, by using a mixture of copper and nickel for the electrode, the electrode component has an effect of suppressing a change in composition of the electrode component into a resistor component due to diffusion of the resistor layer.

[0017] According to the present invention, a mixed powder containing a glass powder having a copper-nickel alloy powder content of more than 97% by weight and a softening point of less than 550 ° C of less than 0 to 3% by weight is provided as a vehicle. After the resistor paste dispersed in the recesses on both sides of the ceramic substrate is printed and dried,
A commercially available metal copper paste is printed and dried on both ends as a lower electrode, and then a metal nickel paste is printed and dried on the lower electrode as an upper electrode. And baking in a neutral atmosphere to alleviate the separation from the substrate due to the internal stress of the resistor film generated during sintering by providing recesses in the substrate, and reducing the glass component to several percent to reduce the glass component Can be minimized in the metal component and at the interface of the sintered particles, and the connection between the resistor and the electrode can be controlled by the printing pattern.
Therefore, the obtained resistor can have low resistance and low TCR. Further, by forming a resistor film on both sides and providing a power supply portion on both sides, it is possible to further reduce the resistance value and to withstand electric power. Further, the obtained resistor film is less likely to reflect laser energy as compared with a metal foil or a plating layer, and thus has an effect capable of laser trimming. Further, by using a mixture of copper and nickel for the electrode, the electrode component has an effect of suppressing a change in composition of the electrode component into a resistor component due to diffusion of the resistor layer.

According to a twelfth aspect of the present invention, a mixed powder containing a copper-nickel alloy powder content of more than 97% by weight and a glass powder having a softening point of less than 550 ° C of less than 0 to 3% by weight is provided as a vehicle. After the resistor paste dispersed in the recesses on one side of the ceramic substrate is completely printed and dried,
A commercially available metal nickel paste is printed and dried on both ends thereof as a lower electrode, and then a metal copper paste is printed and dried on the lower electrode as an upper electrode and baked in a neutral atmosphere. Detachment from the substrate due to the internal stress of the body film can be mitigated by providing recesses in the substrate, and by making the glass component a few percent, the diffusion of the glass component into the metal component and the interface to the sintered particles can be suppressed to a minimum. The connection between the resistor and the electrode can be controlled by the printing pattern. Therefore, the obtained resistor can have low resistance and low TCR. Further, the obtained resistor film is less likely to reflect laser energy as compared with a metal foil or a plating layer, and thus has an effect capable of laser trimming. Further, by using a mixture of copper and nickel for the electrode, the electrode component has an effect of suppressing a change in composition of the electrode component into a resistor component due to diffusion of the resistor layer.

According to a thirteenth aspect of the present invention, a mixed powder containing a glass powder having a copper-nickel alloy powder content of more than 97% by weight and a softening point of less than 550 ° C. of less than 0 to 3% by weight is provided as a vehicle. After the resistor paste dispersed in the recesses on one side of the ceramic substrate is completely printed and dried,
A commercially available metal nickel paste is printed and dried on both ends as a lower electrode, and then a metal copper paste is printed and dried on the lower electrode as an upper electrode. And baking in a neutral atmosphere to alleviate the separation from the substrate due to the internal stress of the resistor film generated during sintering by providing recesses in the substrate, and reducing the glass component to several percent to reduce the glass component Can be minimized in the metal component and at the interface of the sintered particles, and the connection between the resistor and the electrode can be controlled by the printing pattern.
Therefore, the obtained resistor can have low resistance and low TCR. Further, by forming a resistor film on both sides and providing a power supply portion on both sides, it is possible to further reduce the resistance value and to withstand electric power. Further, the obtained resistor film is less likely to reflect laser energy than a metal foil or a plating layer, and thus has an effect capable of laser trimming. Further, by using a mixture of copper and nickel for the electrode, the electrode component has an effect of suppressing a change in composition of the electrode component into a resistor component due to diffusion of the resistor layer.

(Embodiment 1) FIG. 1 is a schematic cross-sectional view of a chip resistor according to a first embodiment of the present invention. In the drawing, reference numeral 3 denotes a resistance layer, which is formed by printing on both sides of a rectangular substrate 1 by a thick film forming technique such as screen printing using a resistor paste having an alloy composition as shown in (Table 1).

Next, an upper surface electrode layer 2 is formed by printing in the same manner as that of the resistance layer 3 so as to be in surface contact with the resistance layer 3 at a pair of opposite ends facing the substrate 1. Are simultaneously fired in a neutral atmosphere or a reducing atmosphere.
Next, U-shaped end face electrode layers 4 are formed on both ends of the substrate 1.

The method for producing the resistor paste will be described below. As the copper-nickel alloy powder, atomized powder having an average particle diameter of 2 μm was used, and a mixed powder obtained by adding glass thereto was used as an inorganic composition. In addition, as a vehicle, a solution obtained by dissolving ethyl cellulose as an organic binder with terpineol was used as an organic composition. These inorganic composition and organic composition were kneaded with a three-roll mill to obtain a thick film resistor paste.

Next, a method for producing the upper electrode paste will be described.
As the copper powder, a powder having an average particle diameter of 2 μm was used as an inorganic composition. In addition, as a vehicle, a solution obtained by dissolving ethyl cellulose as an organic binder with terpineol was used as an organic composition. These inorganic composition and organic composition were kneaded with a three-roll mill to obtain a terminal electrode paste.

Hereinafter, a method of manufacturing a chip resistor will be described. First, a resistor paste is printed on both sides of the substrate (a 96% alumina substrate 6.4 × 3.2 mm), and the paste is printed at a temperature of 100 ° C.
Dry for 0 minutes. An upper electrode paste is screen-printed and dried so as to have a structure in which the upper electrode paste comes into surface contact with the upper surface of the resistor. Next, a commercially available copper electrode paste was applied as a terminal electrode to the end face so as to have a thickness of about 50 to 100 μm, and baked in a nitrogen atmosphere at 900 ° C. for 10 minutes to produce a chip resistor.

An evaluation method of the chip resistor will be described. The inter-terminal electrode distance of the chip resistor was 4.0 mm, the resistor sintered film width was 2.5 mm, the probe was fixed to the terminal electrode portion, and the inter-terminal resistance was determined by a four-terminal method. For the TCR characteristics, the chip resistor was placed in a thermostat and the resistance values at 25 ° C. and 125 ° C. were measured to determine the rate of change. As shown in FIGS. 7 and 8, the change in the resistance value when left at a high temperature is applied to the protective film layer 5 as shown in FIGS.
And the resistance change rate when left at 160 ° C. for 1000 hours was determined.

The structure of the cross section of the fabricated chip resistor was clarified using a scanning electron microscope, an electron beam microanalyzer, and an X-ray micro diffractometer.

The results are shown in (Table 1).

[0028]

[Table 1]

As is clear from Table 1, in the chip resistor obtained in this embodiment, the upper electrode layer 2 is metal-bonded on the resistance layer 3 and the resistance layer 3 is formed on both sides of the substrate 1. This shows that a chip resistor having a low resistance value, a low TCR, and a high reliability can be obtained.

When the chip resistor as described above is manufactured, trimming must be performed in accordance with a required resistance value. Usually, the trimming is performed using a YAG laser. Particles having a particle diameter of greater than 40 μm and a layer thickness of greater than 30 μm cannot be trimmed by a YAG laser, and metal foils and wires cannot be laser trimmed because they reflect laser energy. The chip resistors are laser-trimmable.

(Embodiment 2) FIG. 2 is a schematic sectional view of a chip resistor according to a second embodiment of the present invention. In the drawing, 3 is a resistance layer, and 8 is a metal foil (6.4 × 3.2 mm thickness = 0.04 mm) described in (Table 2). The thick film resistor paste was printed on the metal foil 8 and dried at a temperature of 100 ° C. for 10 minutes. Then, this was fired in a neutral atmosphere or a reducing atmosphere.

For the preparation of the thick film resistor paste, an atomized powder having an average particle diameter of 2 μm was used as the copper-nickel alloy powder, and this was used as an inorganic composition. In addition, as a vehicle, a solution obtained by dissolving ethyl cellulose as an organic binder with terpineol was used as an organic composition. These inorganic composition and organic composition were kneaded with a three-roll mill to obtain a thick film resistor paste.

A method for manufacturing a chip resistor will be described below. First, a thick film resistor paste is printed on the metal foil 8 and
Dry at a temperature of 0 ° C. for 10 minutes. Next, baking was performed at 900 ° C. for 10 minutes in a nitrogen atmosphere to produce a chip resistor.

An evaluation method of the chip resistor will be described. The inter-terminal electrode distance of the chip resistor was 4.0 mm, the resistor sintered film width was 2.5 mm, the probe was fixed to the terminal electrode portion, and the inter-terminal resistance was determined by a four-terminal method. For the TCR characteristics, the chip resistor was placed in a thermostat and the resistance values at 25 ° C. and 125 ° C. were measured to determine the rate of change. As shown in FIG. 9, the change in the resistance value when left at a high temperature was obtained by coating the sintered resistor film with a protective film layer 5 as shown in FIG.

The structure of the cross section of the manufactured chip resistor was clarified using a scanning electron microscope, an electron beam microanalyzer, and an X-ray micro diffractometer.

The results are shown in (Table 2).

[0037]

[Table 2]

As is clear from Table 2, the chip resistor obtained in the present embodiment has a low resistance value, a low TCR, and high reliability by bonding the resistance layer 3 to the metal foil 8 with metal. It can be seen that the chip resistor of No. is obtained.

When the above-described chip resistor is manufactured, trimming must be performed in accordance with a required resistance value. Usually, the trimming is performed using a YAG laser. Particles having a particle diameter of greater than 40 μm and a layer thickness of greater than 30 μm cannot be trimmed by a YAG laser, and metal foils and wires cannot be laser trimmed because they reflect laser energy. The chip resistor can be laser-trimmed, and the resistor can be obtained inexpensively with less production steps.

(Embodiment 3) FIG. 3 is a schematic sectional view of a chip resistor according to a third embodiment of the present invention. In the figure, reference numeral 3 denotes a resistance layer, and 8 denotes a metal foil, which is printed on one surface of the rectangular substrate 1 by a thick film forming technique such as screen printing using a resistor paste having an alloy composition as shown in (Table 3). Has formed.

Next, the upper electrode layer 2 is printed and formed on both ends of the substrate 1 in the same manner as the resistance layer 3 so as to be in surface contact with the resistance layer 3, and the resistance layer 3 and the upper electrode layer 2 are placed in a neutral atmosphere. Alternatively, they are fired simultaneously in a reducing atmosphere. Next, U-shaped end face electrode layers 4 are formed on both ends of the substrate 1.

The method of producing the resistor paste is the same as in the first embodiment. The method for producing the upper surface electrode paste is the same as that in Embodiment 1.

Hereinafter, a method of manufacturing a chip resistor will be described. First, the substrate 1 (96% alumina substrate 6.4 × 3.2 m
m) on the metal foil 8 (3.8 × 2.3 mm thickness = 0.02 m)
m), print the resistor paste on it,
Dry for 10 minutes at a temperature of ° C. The upper surface electrode paste is screen-printed and dried so as to have a structure in which it is in surface contact with the upper surface of the resistor as shown in FIG. Next, using a commercially available copper electrode paste as a terminal electrode, a film thickness of about 5
Coated to a thickness of 0 to 100 μm and 9 in a nitrogen atmosphere
Baking was performed at 00 ° C. for 10 minutes to produce a chip resistor.

The evaluation method of the chip resistor will be described. The inter-terminal electrode distance of the chip resistor was 4.0 mm, the resistor sintered film width was 2.5 mm, the probe was fixed to the terminal electrode portion, and the inter-terminal resistance was determined by a four-terminal method. For the TCR characteristics, the chip resistor was placed in a thermostat and the resistance values at 25 ° C. and 125 ° C. were measured to determine the rate of change. As shown in FIG. 10, the change in resistance value when left at high temperature was obtained by coating the sintered resistor film with a protective film layer 5 as shown in FIG.

The structure of the cross section of the fabricated chip resistor was clarified using a scanning electron microscope, an electron beam microanalyzer, and an X-ray micro diffractometer.

The results are shown in (Table 3).

[0047]

[Table 3]

As is clear from Table 3, the chip resistor obtained in the present embodiment has a low resistance value, a low TCR, and a high reliability by metal-bonding the upper electrode layer 2 on the resistance layer 3. It can be seen that the chip resistor of No. is obtained.

When the chip resistor as described above is manufactured, trimming must be performed in accordance with a required resistance value. Usually, the trimming is performed using a YAG laser. Particles having a particle diameter of greater than 40 μm and a layer thickness of greater than 30 μm cannot be trimmed by a YAG laser, and metal foils and wires cannot be laser trimmed because they reflect laser energy. The chip resistor can be laser-trimmed, and the use of a substrate improves heat radiation of components.

(Embodiment 4) FIG. 4 is a schematic sectional view of a chip resistor according to a fourth embodiment of the present invention. In the figure, 3 is a resistance layer, 9 is a metal wire, and is printed on both surfaces of the rectangular substrate 1 by a thick film forming technique such as screen printing using a resistor paste having an alloy composition as shown in (Table 4). Has formed. Next, the upper electrode layer 2 is printed and formed on both ends of the substrate 1 in the same manner as the resistance layer 3 so as to be in surface contact with the resistance layer 3, and the resistance layer 3 and the upper electrode layer 2 are formed in a neutral atmosphere or a reducing atmosphere. Co-fired inside. Next, U-shaped end face electrode layers 4 are formed on both ends of the substrate 1.

The method of producing the resistor paste is the same as in the first embodiment. The method for producing the upper surface electrode paste is the same as that in Embodiment 1.

Hereinafter, a method for manufacturing a chip resistor will be described. First, the substrate 1 (96% alumina substrate 6.4 × 3.2 m
m) On top of metal wire 9 (diameter = 0.6mm length = 3.8mm)
Was placed and a resistor paste was printed thereon and dried at a temperature of 100 ° C. for 10 minutes. An upper electrode paste is screen-printed and dried so as to have a structure in which the upper electrode paste comes into surface contact with the upper surface of the resistor. Next, using a commercially available copper electrode paste as a terminal electrode, it was applied to the end face so as to have a thickness of about 50 to 100 μm, and baked in a nitrogen atmosphere at 900 ° C. for 10 minutes to produce a chip resistor.

The evaluation of the chip resistor will be described. The inter-terminal electrode distance of the chip resistor was 4.0 mm, the resistor sintered film width was 2.5 mm, the probe was fixed to the terminal electrode portion, and the inter-terminal resistance was determined by a four-terminal method. For the TCR characteristics, the chip resistor was placed in a thermostat and the resistance values at 25 ° C. and 125 ° C. were measured to determine the rate of change. The resistance change during high-temperature storage is as follows.
The resistance value change rate when left for 00 hours was determined.

The cross section of the manufactured chip resistor was clarified by using a scanning electron microscope, an electron beam microanalyzer, and an X-ray micro diffractometer.

The results are shown in (Table 4).

[0056]

[Table 4]

As is clear from Table 4, the chip resistor obtained in the present embodiment has a low resistance value, a low TCR, and a high resistance by connecting the upper electrode layer 2 to the resistance layer 3 with a metal.
It can be seen that a highly reliable chip resistor can be obtained.

When the above-described chip resistor is manufactured, trimming must be performed in accordance with a required resistance value. Usually, the trimming is performed using a YAG laser. Particles having a particle diameter of greater than 40 μm and a layer thickness of greater than 30 μm cannot be trimmed by a YAG laser, and metal foils and wires cannot be laser trimmed because they reflect laser energy. The chip resistor can be laser-trimmed, and can be fixed by forming a slit or the like on a substrate by using a metal wire, so that productivity is good.

(Fifth Embodiment) FIG. 5 is a schematic sectional view of a chip resistor according to a fifth embodiment of the present invention. In the figure, 3 is a resistance layer, 8 is a metal foil shown in (Table 5), and screen printing or the like using a resistor paste having an alloy composition as shown in (Table 5) on one surface of the rectangular substrate 1. It is formed by printing using thick film forming technology. Next, the upper electrode layer 2 is printed and formed on both ends of the substrate 1 in the same manner as the resistance layer 3 so as to be in surface contact with the resistance layer 3, and the resistance layer 3 and the upper electrode layer 2 are formed in a neutral atmosphere or a reducing atmosphere. Co-fired inside. Next, U-shaped end face electrode layers 4 are formed on both ends of the substrate 1. The method for producing the resistor paste is the same as in the first embodiment.

The method for producing the upper electrode paste is the same as in the first embodiment. Hereinafter, a method of manufacturing a chip resistor will be described. First, the substrate 1 (96% alumina substrate 6.4 × 3.
Metal foil 8 (6.4 × 2.5 mm thickness = 2 mm)
0.1 mm). The resistor paste is printed on the surface opposite to the substrate metal foil and dried at a temperature of 100 ° C. for 10 minutes. An upper electrode paste is screen-printed and dried so as to have a structure in which the upper electrode paste comes into surface contact with the upper surface of the resistor.

Then, a commercially available copper electrode paste was applied as a terminal electrode to the end face so as to have a thickness of about 50 to 100 μm, and baked in a nitrogen atmosphere at 900 ° C. for 10 minutes to produce a chip resistor.

A method for evaluating a chip resistor will be described. The inter-terminal electrode distance of the chip resistor was 4.0 mm, the resistor sintered film width was 2.5 mm, the probe was fixed to the terminal electrode portion, and the inter-terminal resistance was determined by a four-terminal method. For the TCR characteristics, the chip resistor was placed in a thermostat and the resistance values at 25 ° C. and 125 ° C. were measured to determine the rate of change. The change in resistance value when left at high temperature was obtained by coating the sintered resistor film with a protective resin, and then determining the rate of change in resistance value when left at 160 ° C. for 1000 hours.

The structure of the cross section of the manufactured chip resistor was clarified using a scanning electron microscope, an electron beam microanalyzer, and an X-ray micro diffractometer.

The results are shown in (Table 5).

[0065]

[Table 5]

As is clear from Table 5, the chip resistor obtained in the present embodiment has a low resistance value, a low TCR, and a low resistance by bonding the upper electrode layer 2 to the resistance layer 3 with metal.
It can be seen that a highly reliable chip resistor can be obtained.

When the chip resistor as described above is manufactured, trimming must be performed in accordance with a required resistance value. Usually, the trimming is performed using a YAG laser. Particles having a particle diameter of greater than 40 μm and a layer thickness of greater than 30 μm cannot be trimmed by a YAG laser, and metal foils and wires cannot be laser trimmed because they reflect laser energy. The chip resistor can be laser-trimmed, and the resistance can be further reduced by using a metal foil.

(Embodiment 6) FIG. 6 is a schematic sectional view of a chip resistor according to a sixth embodiment of the present invention. In the figure, 3 is a resistance layer, 9 is a metal wire shown in (Table 6), and screen printing or the like is performed on both surfaces of the rectangular substrate 1 by using a resistor paste having an alloy composition shown in (Table 9). It is formed by printing using thick film forming technology. Next, the upper electrode layer 2 is printed and formed on both ends of the substrate 1 in the same manner as the resistance layer 3 so as to be in surface contact with the resistance layer 3, and the resistance layer 3 and the upper electrode layer 2 are formed in a neutral atmosphere or a reducing atmosphere. Co-fired inside. Next, U-shaped end face electrode layers 4 are formed on both ends of the substrate 1. The method for producing the resistor paste is the same as in the first embodiment.

The method for producing the upper electrode paste is the same as in the first embodiment. Hereinafter, a method of manufacturing a chip resistor will be described. First, the substrate 1 (96% alumina substrate 6.4 × 3.
Metal wire 9 (diameter = 0.6 mm, length = 3.
8mm). The resistor paste was printed on both sides of the substrate 1 and dried at a temperature of 100 ° C. for 10 minutes. An upper electrode paste is screen-printed and dried so as to have a structure in which the upper electrode paste comes into surface contact with the upper surface of the resistor.

Then, a commercially available copper electrode paste was applied as a terminal electrode to the end face so as to have a thickness of about 50 to 100 μm, and baked in a nitrogen atmosphere at 900 ° C. for 10 minutes to produce a chip resistor.

An evaluation method of the chip resistor will be described. The inter-terminal electrode distance of the chip resistor was 4.0 mm, the resistor sintered film width was 2.5 mm, the probe was fixed to the terminal electrode portion, and the inter-terminal resistance was determined by a four-terminal method. For the TCR characteristics, the chip resistor was placed in a thermostat and the resistance values at 25 ° C. and 125 ° C. were measured to determine the rate of change. As shown in FIG. 11, the change in the resistance value when left at a high temperature was obtained by coating the sintered resistor film with a protective film layer 5 as shown in FIG.

The structure of the cross section of the manufactured chip resistor was clarified by using a scanning electron microscope, an electron beam microanalyzer, and an X-ray micro diffractometer.

The results are shown in (Table 6).

[0074]

[Table 6]

As is clear from Table 6, in the chip resistor obtained in this embodiment, the upper electrode layer 2 is metal-bonded on the resistance layer 3 and the resistance layer 3 is formed on both sides of the substrate 1. This shows that a chip resistor having a low resistance value, a low TCR, and a high reliability can be obtained.

When the above-described chip resistor is manufactured, trimming must be performed in accordance with a required resistance value. Usually, the trimming is performed using a YAG laser. Particles having a particle diameter of greater than 40 μm and a layer thickness of greater than 30 μm cannot be trimmed by a YAG laser, and metal foils and wires cannot be laser trimmed because they reflect laser energy. The chip resistor can be laser-trimmed, can further reduce resistance by using a metal wire, and can be fixed by forming a slit or the like on a substrate, so that productivity is good.

In this embodiment, an example in which the terminal electrode layer conducts the upper and lower surface resistors is shown. However, a through hole or the like is formed in the ceramic base, and a metal paste or metal is buried to conduct the conduction, thereby reducing the resistance. It is also possible to form chip resistors. When a metal foil or a metal wire is used, it is desirable to form a resistor after forming a concave and convex (slit) on the ceramic base and fixing the metal foil and the metal wire to the concave portion. Further, when the protective resin is not used, the rate of change in resistance value when left at a high temperature is higher than when the protective resin is used.

[0078]

As described above, according to the present invention, a low TC
A resistor with low R, low resistance and high reliability can be formed by a thick film forming method, and a process with good productivity in which resistance can be adjusted using laser trimming can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of Embodiment 1 of the present invention.

FIG. 2 is a schematic sectional view of Embodiment 2 of the present invention.

FIG. 3 is a schematic sectional view of Embodiment 3 of the present invention.

FIG. 4 is a schematic sectional view of Embodiment 4 of the present invention.

FIG. 5 is a schematic sectional view of a fifth embodiment of the present invention.

FIG. 6 is a schematic sectional view of Embodiment 6 of the present invention.

FIG. 7 is a perspective view of the first embodiment of the present invention.

FIG. 8 is a schematic sectional view of Embodiment 1 of the present invention.

FIG. 9 is a schematic sectional view of Embodiment 2 of the present invention.

FIG. 10 is a schematic sectional view of Embodiment 3 of the present invention.

FIG. 11 is a schematic sectional view of Embodiment 6 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Upper electrode layer 3 Resistance layer 4 End electrode layer 5 Protective film layer

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5E032 BA07 BB01 BB13 CA02 CC06 CC18 5E033 AA18 AA22 BA03 BD12 BE01 BE04 BF05 BG02 BH02

Claims (13)

[Claims] 1. A resistor paste containing at least a copper-nickel alloy powder is printed in a concave portion of a ceramic substrate having a concave portion on one side, and both ends thereof are connected with a metal or a metal paste having higher conductivity than the copper-nickel alloy. A chip resistor obtained by firing in a neutral atmosphere. 2. A resistive paste containing at least a copper-nickel alloy powder is printed in a concave portion of a ceramic substrate having concave portions on both sides, and both ends thereof are connected with a metal or a metal paste having higher conductivity than the copper-nickel alloy. A chip resistor obtained by firing in a neutral atmosphere. 3. A resistor paste containing at least a copper-nickel alloy powder is printed in a recess of a ceramic substrate having a recess having a step on one surface, and a metal having higher conductivity than the copper-nickel alloy is printed on both ends thereof. Chip resistor obtained by connecting with a metal paste and firing in a neutral atmosphere. 4. A resistor having at least copper-nickel alloy powder is printed in a recess of a ceramic substrate having a recess having a step on both surfaces, and a metal having a higher conductivity than the copper-nickel alloy on both ends thereof. Chip resistor obtained by connecting with a metal paste and firing in a neutral atmosphere. 5. A resistor paste containing at least a copper-nickel alloy powder is printed in a concave portion of a ceramic substrate having a concave portion having at least two sides having no step on one side, and a higher conductivity than the copper-nickel alloy is applied to both ends thereof. A chip resistor obtained by connecting with a metal or a metal paste having the above and firing in a neutral atmosphere. 6. A resistor paste containing at least a copper-nickel alloy powder is printed in a concave portion of a ceramic substrate having a concave portion having at least two sides having no steps on both surfaces, and a higher conductivity than the copper-nickel alloy is applied to both ends thereof. A chip resistor obtained by connecting with a metal or a metal paste having the above and firing in a neutral atmosphere. 7. A resistor paste containing at least a copper-nickel alloy powder is printed on a concave portion of a ceramic substrate having a concave portion having a concave and convex bottom surface on one side, and copper paste is printed on both ends thereof.
A chip resistor obtained by connecting with a metal or metal paste having higher conductivity than nickel alloy and firing in a neutral atmosphere. 8. A resistor paste containing at least a copper-nickel alloy powder is printed in a concave portion of a ceramic substrate having concave portions having a concave and convex bottom surface on both sides, and copper-containing paste is applied to both ends thereof.
A chip resistor obtained by connecting with a metal or metal paste having higher conductivity than nickel alloy and firing in a neutral atmosphere. 9. Masking both ends of a concave portion of a ceramic substrate having a concave portion, printing a resistor paste containing an alloy powder containing at least copper-nickel, removing the masking, and having a higher conductivity than the copper-nickel alloy. A chip resistor obtained by printing a metal paste having the composition and firing it in a neutral atmosphere. 10. A resistive paste containing at least a copper-nickel alloy powder is printed in a concave portion of a ceramic substrate having a concave portion on one side, and a lower copper-upper nickel paste is connected to both ends of the resistor paste and fired in a neutral atmosphere. Chip resistor obtained by: 11. A resistor paste containing at least a copper-nickel alloy powder is printed in a concave portion of a ceramic substrate having concave portions on both sides, and a lower copper-upper nickel paste is connected to both ends thereof and fired in a neutral atmosphere. Chip resistor obtained by: 12. A resistor paste containing at least a copper-nickel alloy powder is printed in a concave portion of a ceramic base having a concave portion on one side, and a lower layer nickel-upper layer copper paste is connected to both ends thereof and fired in a neutral atmosphere. Chip resistor obtained by: 13. A resistive paste containing at least a copper-nickel alloy powder is printed in a concave portion of a ceramic base having concave portions on both surfaces, connected to both ends with a lower nickel-upper copper paste and fired in a neutral atmosphere. Chip resistor obtained by: