CN117561583A

CN117561583A - Resistor paste, chip resistor, and glass particles

Info

Publication number: CN117561583A
Application number: CN202280045496.7A
Authority: CN
Inventors: 青池祐树; 伊藤浩克; 松岛贤一; 中山祥吾; 藤田知宏; 大林孝志
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2021-08-18
Filing date: 2022-08-10
Publication date: 2024-02-13

Abstract

The problem addressed by the present disclosure is to enable a resistor to achieve a good balance between high resistivity and low TCR. The resistive paste according to the present disclosure includes metal particles, insulating particles, glass particles, and metal silicide. The metal particles comprise copper and nickel. The insulating particles contain at least one substance selected from the group consisting of aluminum oxide, zirconium oxide, zinc oxide, and boron nitride. The chip resistor (1) according to the present disclosure has a resistor (13) and a substrate (11). The resistor (13) is formed on the substrate (11) while being formed of the above-mentioned resistive paste.

Description

Resistor paste, chip resistor, and glass particles

Technical Field

The present disclosure relates generally to a resistive paste, a chip resistor, and glass particles, and in particular to a resistive paste containing metal particles, a chip resistor including a resistive element containing the resistive paste as a material, and glass particles contained in the resistive paste.

Background

Patent document 1 describes a resistive paste including a conductive portion formed of metal particles, an inorganic binder component formed of low-melting glass particles, a resistance value adjusting component formed of non-conductive inorganic particles (insulating particles), and an organic vehicle. The metal particles comprise copper and nickel. The non-conductive inorganic particles comprise, for example, alumina.

The resistance paste described in patent document 1 contains a resistance value adjusting component added thereto, and thus the specific resistance of a resistance element containing the resistance paste as a material is improved, but increasing the addition amount of the resistance value adjusting component in an attempt to further improve the specific resistance may excessively lower the temperature coefficient of resistance (hereinafter referred to as "TCR") of the resistance element.

Reference list

Patent literature

Patent document 1: JP 2015-46567A

Disclosure of Invention

It is an object of the present disclosure to provide a resistive paste, chip resistor and glass particles configured to achieve both high specific resistance and low TCR of a resistive element.

A resistive paste according to one aspect of the present disclosure includes metal particles, insulating particles, glass particles, and metal silicide. The metal particles comprise copper and nickel. The insulating particles include at least one of aluminum oxide, zirconium oxide, zinc oxide, or boron nitride.

A resistive paste according to another aspect of the present disclosure includes metal particles, insulating particles, metal silicide, and glass particles. The metal particles comprise copper and nickel. The insulating particles include at least one of aluminum oxide, zirconium oxide, zinc oxide, or boron nitride. The glass particles comprise at least boron oxide and aluminum oxide. When a resistive element of a chip resistor is formed from the resistive paste, a nickel compound containing nickel silicide is produced from the resistive paste.

A chip resistor according to one aspect of the present disclosure includes a resistive element and a substrate. The resistive element includes the resistive paste as a material and is disposed on the substrate.

Glass particles according to one aspect of the present disclosure are included in the resistive paste.

Drawings

Fig. 1 is a sectional view of a chip resistor including a resistive element including a resistive paste according to the first and second embodiments as a material; and

fig. 2 is a graph of TCR versus the ratio of glass particles B contained in the resistive paste according to the second embodiment relative to the total amount of glass particles a and B.

Detailed Description

The resistive paste, chip resistor, and glass particles according to the first and second embodiments will be described below with reference to the accompanying drawings. Fig. 1 referred to in the following description of the first embodiment and the second embodiment is a schematic diagram. That is, the ratio of the sizes (including thicknesses) of the respective constituent elements shown in the drawings does not always reflect their actual size ratios.

(first embodiment)

(1) Construction of resistor paste

First, the constitution of the resistive paste according to the first embodiment will be described.

The resistive paste according to the first embodiment is a material for a resistive element 13 (see fig. 1) of the chip resistor 1 to be described later, and is used to form the resistive element 13.

The resistive paste according to the first embodiment includes metal particles, insulating particles, glass particles, an organic carrier, and metal silicide.

The metal particles include copper (Cu) and nickel (Ni). More specifically, the metal particles are a combination of copper particles and nickel particles. Note that the metal particles are not limited to a combination of copper particles and nickel particles, but may be alloy particles of copper and nickel. Further, the metal particles may be a combination of copper particles and alloy particles, a combination of nickel particles and alloy particles, or a combination of copper particles, nickel particles, and alloy particles. The metal particles form a conductive path in the resistive element 13 (see fig. 1) after baking. The metal particles comprise at least copper and nickel, and may also comprise other metals.

The insulating particles include alumina (Al ₂ O ₃ ) Zirconium oxide (ZrO) ₂ ) At least one of zinc oxide (ZnO) or Boron Nitride (BN). In the resistive paste according to the first embodiment, the insulating particles include alumina. The insulating particles suppress melting and flowing of glass particles, which will be described later, to thereby suppress breakage of the conductive paths, while reducing the content of metal particles in the baked resistive element 13 (see fig. 1) to increase the resistance value.

The glass particles comprise, for example, silicon oxide (e.g., siO ₂ ). The glass particles may contain oxides other than silicon oxide. Examples of other oxides include boron oxide (B) ₂ O ₃ ). While the glass particles improve adhesion by improving wettability to a substrate 11 (see fig. 1) to be described later, the glass particles melt and solidify throughout the resistive element 13, thereby toughening the resistive element 13. In addition, the glass particles are insulators, and thus have a function of adjusting the resistance value.

The organic carrier includes at least one of, for example, an organic binder or an organic solvent. In the resistive paste according to the first embodiment, the organic vehicle includes both an organic binder and an organic solvent. The organic binder is, for example, a cellulose-based resin or an acrylic resin-based resin. The organic solvent is for example terpineol or butyl diglycol acetate. The mass percentage of the organic carrier is preferably, for example, 5 to 200, more preferably 10 to 150, and still more preferably 20 to 100, under the condition that the metal particles are set to 100.

The resistive paste contains as a metal silicide at least one of the following: titanium silicide (TiSi) ₂ ) Zirconium silicide (ZrSi) ₂ ) Hafnium silicide (HfSi) ₂ ) Niobium silicide (NbSi) ₂ ) Tantalum silicide (TaSi) ₂ ) Chromium silicide (CrSi) ₂ ) Tungsten silicide (WSi) ₂ ) Molybdenum silicide (MoSi) ₂ ) Iron silicide (FeSi) ₂ ) Magnesium silicide (Mg) ₂ Si), sodium silicide (Na ₂ Si) or platinum silicide (PtSi). The resistive paste according to the first embodiment contains titanium silicide as the metal silicide.

In the resistive paste according to the first embodiment, baking causes a reaction between the metal silicide and the metal particles (copper and nickel), and in response to the reaction, the composition of copper and nickel in the metal particles changes, and nickel silicide (Ni ₃₁ Si ₁₂ ). As a result, the TCR of the resistive element 13 (see fig. 1) formed by baking can be improved. That is, it becomes possible to suppress the decrease in TCR with the increase in the amount of the insulating particles added.

(2) Construction of chip resistor

Next, a chip resistor 1 according to a first embodiment will be described with reference to fig. 1.

As shown in fig. 1, a chip resistor 1 according to the first embodiment includes a substrate 11, a plurality of (two in the example shown in the drawing) upper electrodes 12, a resistive element 13, a protective film 14, a plurality of (two in the example shown in the drawing) lower electrodes 15, and a plurality of (two in the example shown in the drawing) end face electrodes 16. In addition, the chip resistor 1 according to the first embodiment further includes a plurality of (two in the example shown in the drawing) first plating layers 17, a plurality of (two in the example shown in the drawing) second plating layers 18, and a plurality of (two in the example shown in the drawing) third plating layers 19. That is, the chip resistor 1 according to the first embodiment includes the substrate 11 and the resistive element 13.

(2.1) substrate

The substrate 11 is, for example, a ceramic substrate. The material used for the ceramic substrate is, for example, an alumina sintered body having an alumina content percentage of 96% or more. The substrate 11 has a rectangular shape in a plan view in the first direction D1. As shown in fig. 1, the substrate 11 has a first main surface (upper surface) 111, a second main surface (lower surface) 112, and an outer peripheral surface 113. The first main surface 111 and the second main surface 112 face each other in the first direction D1. The first main surface 111 and the second main surface 112 are each flat surfaces along a second direction D2 perpendicular to the first direction D1. Further, the outer peripheral surface 113 includes four sides along the first direction D1. The first direction D1 is a direction (up-down direction in fig. 1) parallel to the thickness direction defined with respect to the substrate 11. The second direction D2 is a direction (left-right direction in fig. 1) parallel to the longitudinal direction or the width direction (short direction) of the substrate 11.

(2.2) upper electrode

A plurality of upper electrodes 12 are disposed on the first major surface 111 of the substrate 11. In the example shown in fig. 1, a plurality of upper electrodes 12 are provided at both ends in the second direction D2 on the first main surface 111 of the substrate 11. Examples of materials for the plurality of upper electrodes 12 include copper (Cu) based alloys. The plurality of upper electrodes 12 are formed, for example, by printing a thick film material and baking the thick film material.

(2.3) resistance element

The resistive element 13 is disposed on the first major surface 111 of the substrate 11. In the example shown in fig. 1, the resistive element 13 is provided at a central portion on the first main surface 111 of the substrate 11. Examples of the material for the resistive element 13 include the above-described resistive paste. Both ends of the resistive element 13 in the second direction D2 are in contact with the plurality of upper electrodes 12 and electrically connected to the plurality of upper electrodes 12. The resistive element 13 has a rectangular shape in a plan view in the first direction D1, for example, but may have an arbitrary shape according to the resistance value of the resistive element 13.

(2.4) protective film

The protective film 14 is a film for protecting the resistive element 13. The protective film 14 covers at least a part of the resistive element 13. In the example shown in fig. 1, the protective film 14 covers the entire area (entire portion) of the resistive element 13. Examples of the material for the protective film 14 include epoxy resin. The protective film 14 has a rectangular shape in a plan view in the first direction D1, for example, but may have an arbitrary shape matching the shape of the resistive element 13. The material for the protective film 14 is not limited to epoxy resin, but may be, for example, polyimide resin.

(2.5) lower electrode

A plurality of lower electrodes (back electrodes) 15 are provided on the second main surface 112 of the substrate 11. In the example shown in fig. 1, a plurality of lower electrodes 15 are provided at both ends in the second direction D2 on the second main surface 112 of the substrate 11. The plurality of lower electrodes 15 are in one-to-one correspondence with the plurality of upper electrodes 12. Examples of the material for the plurality of lower electrodes 15 include Cu-based alloys. The plurality of lower electrodes 15 are formed, for example, by printing a thick film material and baking the thick film material.

(2.6) end face electrode

A plurality of end face electrodes 16 are provided so as to cover the outer peripheral surface 113 of the substrate 11. In the example shown in fig. 1, a plurality of end face electrodes 16 are provided to cover two sides in the second direction D2 among four sides included in the outer peripheral surface 113 of the substrate 11. The plurality of end face electrodes 16 are in one-to-one correspondence with the plurality of upper electrodes 12 and in one-to-one correspondence with the plurality of lower electrodes 15. Examples of materials for the plurality of end face electrodes 16 include a mixture of carbon powder, silver (Ag), and epoxy. In the first direction D1, each of the plurality of end face electrodes 16 has a first end (upper end) in contact with a corresponding upper electrode 12 of the plurality of upper electrodes 12 and a second end (lower end) in contact with a corresponding lower electrode 15 of the plurality of lower electrodes 15. Accordingly, the plurality of upper electrodes 12 and the plurality of lower electrodes 15 are electrically connected via the plurality of end face electrodes 16.

(2.7) first coating

The plurality of first plating layers 17 include, for example, copper (Cu) plating layers. In the example shown in fig. 1, a plurality of first plating layers 17 cover a plurality of upper electrodes 12, a plurality of lower electrodes 15, and a plurality of end face electrodes 16 at both ends of the substrate 11 in the second direction D2. Further, a plurality of first plating layers 17 are in contact with the surface of the protective film 14. In the chip resistor 1 according to the first embodiment, the provision of the first plating layer 17 enables adjustment of the resistance value of the chip resistor 1. Note that the first plating layer 17 may be omitted.

(2.8) second coating

The plurality of second plating layers 18 include, for example, nickel (Ni) plating layers. In the example shown in fig. 1, a plurality of second plating layers 18 cover a plurality of first plating layers 17 at both ends of the substrate 11 in the second direction D2. Further, a plurality of second plating layers 18 are in contact with the protective film 14.

(2.9) third coating

The plurality of third plating layers 19 includes, for example, tin (Sn) plating layers. In the example shown in fig. 1, a plurality of third plating layers 19 cover a plurality of second plating layers 18 at both ends of the substrate 11 in the second direction D2. Further, a plurality of third plating layers 19 are in contact with the surface of the protective film 14.

(3) Method for manufacturing chip resistor

Next, a method for manufacturing the chip resistor 1 according to the first embodiment will be described.

The method for manufacturing the chip resistor 1 according to the first embodiment includes first to ninth steps.

The first step includes preparing the substrate 11. More specifically, in the first step, a substrate body is prepared as a base (base) of the substrate 11 of each of the plurality of chip resistors 1. The substrate body is, for example, a ceramic substrate. The material for ceramic substrate used as the substrate body is, for example, an alumina sintered body having an alumina content percentage of 96% or more.

The second step includes forming a plurality of lower electrodes 15 of each of the plurality of chip resistors 1 on the second main surface of the substrate body. More specifically, in the second step, for example, a thick film material is printed and then baked to form a Cu-based alloy film on the second main surface of the substrate body, thereby forming a plurality of lower electrodes 15 of each of the plurality of chip resistors 1. The second main surface of the substrate body is a surface of the second main surface 112 of the substrate 11 to be each of the plurality of chip resistors 1.

The third step includes forming a plurality of upper electrodes 12 on the first main surface of the substrate body. The first main surface of the substrate body is a surface of the first main surface 111 of the substrate 11 to be each of the plurality of chip resistors 1. More specifically, in the third step, for example, a thick film material is printed and then baked to form a Cu-based alloy film on the first main surface of the substrate body, thereby forming the plurality of upper electrodes 12 of each of the plurality of chip resistors 1.

The fourth step includes forming the resistive element 13 of each of the plurality of chip resistors 1. More specifically, in the fourth step, the resistive paste is printed on the first main surface of the substrate main body and then baked to form the resistive element 13. At this time, in the resistive element 13, metal silicide (titanium silicide) and metal particles (copper and nickel) react with each other, thereby generating metal silicide (nickel silicide) different from the metal silicide (titanium silicide). That is, in the chip resistor 1 according to the first embodiment, the resistance element 13 contains nickel silicide.

The fifth step includes forming the protective film 14 of each of the plurality of chip resistors 1. More specifically, in the fifth step, an epoxy resin is coated to cover the entire resistive element 13, and then the epoxy resin is thermally cured, thereby forming the protective film 14. As shown in fig. 1, the protective film 14 covers contact portions of the plurality of upper electrodes 12 with the resistive element 13.

The sixth step includes dividing the plurality of chip resistors (excluding the end face electrode 16, the first plating layer 17, the second plating layer 18, and the third plating layer 19) integrally formed through the first step to the fifth step into a plurality of strip-shaped chip resistors excluding the end face electrode 16, the first plating layer 17, the second plating layer 18, and the third plating layer 19. More specifically, in the sixth step, for example, stress is applied to the plurality of chip resistors integrally formed by the upper roller and the lower roller (not shown), thereby dividing the plurality of chip resistors into a plurality of strip-shaped chip resistors.

The seventh step includes forming a plurality of end face electrodes 16 for each of the plurality of slatted chip resistors. More specifically, in the seventh step, for example, an end face electrode paste (not shown) made of the mixture is set on a roller (not shown) made of stainless steel, and then the roller is rotated, thereby forming a plurality of end face electrodes 16 of each of the plurality of slat-type chip resistors. Accordingly, for each of the plurality of the strip-like chip resistors, the plurality of upper electrodes 12 and the plurality of lower electrodes 15 are electrically connected via the plurality of end face electrodes 16.

The eighth step includes rotating the roller to divide the plurality of strip-like chip resistors into individual pieces of the chip resistors.

The ninth step includes forming first to third plating layers 17 to 19 of each of the plurality of chip resistors. More specifically, in the ninth step, three plating layers, that is, the first plating layer 17, the second plating layer 18, and the third plating layer 19 are formed in order for each of the plurality of chip resistors.

Through the above-described first to ninth steps, the chip resistor 1 according to the first embodiment can be manufactured.

(4) Characteristics of chip resistor

Next, characteristics of the chip resistor 1 including the resistive paste according to the first embodiment will be described with reference to comparative examples. The volume resistivity of the chip resistor 1 is preferably, for example, 200 μΩ·cm or more. Further, the TCR of the chip resistor 1 is preferably, for example, greater than or equal to-50 ppm/. Degree.C.and less than or equal to +50 ppm/. Degree.C..

First, the resistor paste in comparative example 1 contains metal particles, glass particles, an organic vehicle, and insulating particles. The metal particles comprise copper and nickel. The ratio of copper to nickel in the metal particles was 6:4. Further, the insulating particles contain alumina. In comparative example 1, as the proportion of insulating particles (alumina) in the resistive paste increases, the resistance value of the resistive element including the resistive paste as a material increases, but the TCR of the resistive element excessively decreases.

In addition, the resistor paste in comparative example 2 includes metal particles, glass particles, an organic carrier, and metal silicide. The metal particles comprise copper and nickel. The ratio of copper to nickel in the metal particles was 55:45. In addition, the metal silicide is titanium silicide. In comparative example 2, as the proportion of metal silicide (titanium silicide) in the resistive paste increases, the resistance value of the resistive element including the resistive paste as a material increases, and the TCR of the resistive element also increases.

In contrast, in the first embodiment, the resistive paste contains metal particles, glass particles, insulating particles, an organic carrier, and metal silicide. The metal particles comprise copper and nickel. The ratio of copper to nickel in the metal particles was 55:45. Further, the insulating particles include aluminum oxide, and the metal silicide includes titanium silicide.

In one example, when the proportion of the metal particles is 70 wt%, the proportion of the glass particles is 7 wt%, the proportion of the insulating particles (alumina) is 20 wt%, and the proportion of the metal silicide (titanium silicide) is 3 wt% in the resistance paste, the resistance value of the resistance element 13 including the resistance paste as a material is 364mΩ, and the TCR of the resistance element 13 is-19 ppm. Here, the volume of the resistive element 13 is 5.44×10 ^-2 mm ³ (length 1.6 mm. Times. Width 1.7 mm. Times. Thickness 20. Mu.m), the volume resistivity of the resistive element 13 including the resistive paste according to the first embodiment as a material satisfies the above-described reference. Further, in the resistive element 13 including the resistive paste according to the first embodiment as a material, TCR at the temperature change from 25 ℃ to 125 ℃ is-19 ppm, and thus, the above-described reference baseline of TCR is satisfied. In summary, when the resistive element 13 is formed of the resistive paste according to the first embodiment, the TCR of the resistive element 13 may be reduced while the resistance value of the resistive element 13 is increased. That is, the resistive paste according to the first embodiment enables to achieve both high specific resistance and low TCR of the resistive element 13.

(5) Effects of

As described above, the resistive paste according to the first embodiment contains insulating particles. Therefore, when the resistive element 13 of the chip resistor 1 is formed of the resistive paste according to the first embodiment, the specific resistance of the resistive element 13 can be increased. Further, as described above, the resistive paste according to the first embodiment further includes a metal silicide (e.g., titanium silicide). Therefore, when the resistive element 13 of the chip resistor 1 is formed of the resistive paste according to the first embodiment, it is possible to suppress excessive decrease in TCR of the resistive element 13 due to increase in the addition amount of the insulating particles. That is, the resistive paste according to the first embodiment enables to achieve both high specific resistance and low TCR of the resistive element 13.

(6) Variation scheme

The first embodiment is merely one example of various embodiments of the present disclosure. The first embodiment may be variously changed according to design or the like as long as the object of the present disclosure is achieved. Variations of the first embodiment will be described below. Note that any of the variations described below may be appropriately combined.

In the first embodiment, the resistive paste contains titanium silicide as the metal silicide, but the resistive paste may contain metal silicide other than titanium silicide. The resistive paste may contain, for example, the following as metal silicide: zirconium silicide, hafnium silicide, niobium silicide, tantalum silicide, chromium silicide, tungsten silicide, molybdenum silicide, iron silicide, magnesium silicide, sodium silicide, or platinum silicide. In addition, the resistive paste may contain two or more of the above materials as metal silicide. In general terms, the resistive paste comprises at least one of the following as metal silicide: titanium silicide, zirconium silicide, hafnium silicide, niobium silicide, tantalum silicide, chromium silicide, tungsten silicide, molybdenum silicide, iron silicide, magnesium silicide, sodium silicide, or platinum silicide.

In the first embodiment, the resistive paste contains alumina as insulating particles, but the resistive paste may contain insulating particles other than alumina. The resistive paste may contain zirconia, zinc oxide, or boron nitride as insulating particles. Further, the resistive paste may contain two or more of the above materials as insulating particles. In general, the resistor paste contains at least one of alumina, zirconia, zinc oxide, or boron nitride as insulating particles.

In the first embodiment, each end face electrode 16 has a U-shape when viewed in a direction (a direction perpendicular to the paper surface of fig. 1) perpendicular to both the first direction D1 and the second direction D2. However, the shape of each end face electrode 16 is not limited to the U-shape, but may be, for example, an I-shape in the first direction D1. In this case, a first end (upper end) of each end face electrode 16 in the first direction D1 is in contact with a side face of a corresponding one of the upper electrodes 12, and a second end (lower end) of each end face electrode 16 in the first direction D1 is in contact with a side face of a corresponding one of the lower electrodes 15. Accordingly, the plurality of upper electrodes 12 and the plurality of lower electrodes 15 may be electrically connected via the plurality of end face electrodes 16.

(second embodiment)

The resistive paste, the chip resistor 1, and the glass particles according to the second embodiment will be described. With respect to the chip resistor 1 according to the second embodiment, parts similar to those of the chip resistor 1 according to the first embodiment are denoted by the same reference numerals, and a description thereof may be omitted.

The resistive paste according to the second embodiment is different from the resistive paste according to the first embodiment in that the composition of the glass particles is different from that in the first embodiment.

(1) Construction of resistor paste

The resistive paste according to the second embodiment includes metal particles (metal conductors), insulating particles (insulators), metal silicide, and glass particles (glass). That is, glass particles are contained in the resistor paste. In addition, the resistive paste according to the second embodiment further comprises an organic vehicle.

The metal particles comprise copper and nickel. In a second embodiment, the metal particles comprise, for example, a copper-nickel alloy. The metal particles form a conductive path in the resistive element 13 (see fig. 1) after baking. The metal particles comprise at least copper and nickel, and may also comprise other metals.

The insulating particles include at least one of aluminum oxide, zirconium oxide, zinc oxide, or boron nitride. In a second embodiment, the insulating particles comprise, for example, alumina. The insulating particles suppress melting and flowing of glass particles, which will be described later, to thereby suppress breakage of the conductive paths, while reducing the content of metal particles in the baked resistive element 13 (see fig. 1) to increase the resistance value.

The metal silicide includes, for example, titanium silicide.

The glass particles contain boron oxide (B) ₂ O ₃ ) As a main component, silicon oxide (SiO ₂ ) Alumina (Al) ₂ O ₃ ) And tantalum oxide (Ta) ₂ O ₅ ) And contains at least one of magnesium oxide (MgO), calcium oxide (CaO) or barium oxide (BaO) as a minor component. In a second embodiment, the glass particles comprise three of magnesium oxide, calcium oxide, and barium oxide.

The glass particles react with copper, nickel and metal silicide (titanium silicide) in the baking step of the resistive paste, thereby generating nickel silicide (Ni ₃₁ Si ₁₂ ) And nickel aluminum boride (Ni ₂₀ Al ₃ B ₆ ). These nickel silicide and nickel aluminum boride have a function of adjusting the Temperature Coefficient of Resistance (TCR) of the resistive element 13, which will be described later. In the second embodiment, glass particles B to be described later correspond to the above-described glass particles.

In addition, in order to improve the adhesion between the substrate 11 and the resistive element 13, which will be described later, while melting and solidifying the entire resistive element 13 to toughen the resistive element 13, the resistive paste may further contain glass particles containing lead oxide (PbO) as a main component, such as glass particles a, which will be described later. Note that, in order not to suppress the formation of nickel silicide and nickel aluminum boride, the proportion of lead oxide contained in the individual glass particles (glass particles a) is preferably set to 80% by weight or less, and the proportion of the total amount of lead oxide contained in the glass particles a and lead oxide contained in the glass particles B in the total amount of glass particles a and B is preferably set to 45% by weight or less. For example, the glass particles a contain lead oxide as a main component, and boron oxide, silicon oxide, and zinc oxide as minor components. In addition, the glass particles are insulators, and thus have a function of adjusting the resistance value.

In the resistive paste according to the second embodiment, as described above, the glass particles (glass particles B) contain at least boron oxide and aluminum oxide. Further, in the resistive paste according to the second embodiment, the glass particles (glass particles B) further contain silicon oxide, tantalum oxide, magnesium oxide, calcium oxide, and barium oxide.

The organic carrier includes at least one of, for example, an organic binder or an organic solvent. In the resistive paste according to the second embodiment, the organic vehicle includes both an organic binder and an organic solvent. The organic binder is, for example, a cellulose-based resin or an acrylic resin-based resin. The organic solvent is for example terpineol or butyl diglycol acetate. The mass percentage of the organic carrier is preferably, for example, 5 to 200, more preferably 10 to 150, and still more preferably 20 to 100, with the metal ion set to 100.

(2) Construction of chip resistor

Next, a chip resistor 1 according to a second embodiment will be described with reference to fig. 1.

As shown in fig. 1, a chip resistor 1 according to the second embodiment includes a substrate 11, a plurality of (two in the example shown in the drawing) upper electrodes 12, a resistive element 13, a protective film 14, a plurality of (two in the example shown in the drawing) lower electrodes 15, and a plurality of (two in the example shown in the drawing) end face electrodes 16. In addition, the chip resistor 1 according to the second embodiment further includes a plurality of (two in the example shown in the drawing) first plating layers 17, a plurality of (two in the example shown in the drawing) second plating layers 18, and a plurality of (two in the example shown in the drawing) third plating layers 18. In summary, the chip resistor 1 according to the second embodiment includes: a substrate 11; and a resistive element 13 containing the above electrode paste as a material and provided on the substrate 11.

The resistive element 13 contains a nickel compound. The nickel compound comprises, for example, nickel silicide. The nickel silicide is, for example, nickel silicide (Ni ₃₁ Si ₁₂ ). The nickel compound further comprises nickel aluminum boride. The nickel aluminum boride is, for example, nickel aluminum boride (Ni ₂₀ Al ₃ B ₆ ). In other words, when the resistive element 13 of the chip resistor 1 is formed of the above-described resistive paste, a nickel compound containing nickel silicide is generated.

(3) Method for manufacturing chip resistor

Next, a method for manufacturing the chip resistor 1 according to the second embodiment will be described.

The method for manufacturing the chip resistor 1 according to the second embodiment includes first to eighth steps.

The first step includes preparing the substrate 11. More specifically, in the first step, a substrate body that is a substrate of the substrate 11 of each of the plurality of chip resistors 1 is prepared. The substrate body is, for example, a ceramic substrate. The material for the ceramic substrate as the substrate body is, for example, an alumina sintered body having an alumina content percentage of 96% or more.

The second step includes forming a plurality of upper electrodes 12 on the first main surface of the substrate body. The first main surface of the substrate body is a surface of the first main surface 111 of the substrate 11 to be each of the plurality of chip resistors 1. More specifically, in the second step, for example, a thick film material is printed and then baked to form a Cu-based alloy film on the first main surface of the substrate body, thereby forming the plurality of upper electrodes 12 of each of the plurality of chip resistors 1.

The third step includes forming the resistive element 13 of each of the plurality of chip resistors 1. More specifically, in the third step, the resistive paste is printed on the first main surface of the substrate main body and then baked to form the resistive element 13. At this time, in the resistive element 13, metal silicide (titanium silicide) and metal particles (copper and nickel) react with each other via glass particles, thereby generating metal silicide different from the metal silicide (titanium silicide), specifically nickel silicide (Ni ₃₁ Si ₁₂ ). In addition, at this time, titanium in the titanium silicide contained in the resistive paste is absorbed into the glass particles, and silicon in the titanium silicide reacts with the metal particles (copper and nickel), and therefore, almost all of the titanium silicide contained in the resistive paste disappears. In addition, the metal particles (copper and nickel) react directly with the glass particles, thereby further generating metal borides, in particular nickel aluminium boride (Ni ₂₀ Al ₃ B ₆ ). Therefore, in the chip type electric according to the second embodimentIn the resistor 1, the resistive element 13 includes at least nickel silicide (nickel silicide).

The fourth step includes forming the protective film 14 of each of the plurality of chip resistors 1. More specifically, in the fourth step, an epoxy resin is coated to cover the entire resistive element 13, and then the epoxy resin is thermally cured, thereby forming the protective film 14. As shown in fig. 1, the protective film 14 covers contact portions of the plurality of upper electrodes 12 with the resistive element 13.

The fifth step includes forming a plurality of lower electrodes 15 of each of the plurality of chip resistors 1 on the second main surface of the substrate body. More specifically, in the second step, for example, a thick film material is printed and then baked to form a Cu-based alloy film on the second main surface of the substrate main body, thereby forming a plurality of lower electrodes 15 of each of the plurality of chip resistors 1. The second main surface of the substrate body is a surface of the second main surface 112 of the substrate 11 to be each of the plurality of chip resistors 1.

The sixth step includes cutting the plurality of chip resistors 1 integrally formed through the first to fifth steps into individual pieces of the chip resistor 1. More specifically, in the sixth step, the plurality of chip resistors 1 integrally formed are cut into individual pieces of the chip resistor 1, for example, using a laser or by cutting.

The seventh step includes forming a plurality of end face electrodes 16 of each of the individual plurality of pieces of the chip resistor 1. More specifically, in the seventh step, for example, the end face electrode paste (not shown) made of the mixture is set on a roller (not shown) made of stainless steel, and then the roller is rotated, thereby forming the plurality of end face electrodes 16 of each of the plurality of chip resistors 1. Accordingly, for each of the plurality of chip resistors 1, the plurality of upper electrodes 12 and the plurality of lower electrodes 15 are electrically connected via the plurality of end face electrodes 16.

The eighth step includes forming first to third plating layers 17 to 19 of each of the plurality of chip resistors. More specifically, in the eighth step, three plating layers, that is, the first plating layer 17, the second plating layer 18, and the third plating layer 19 are formed in order for each of the plurality of chip resistors 1.

Through the above-described first to eighth steps, the chip resistor 1 according to the second embodiment can be manufactured.

Note that in the above-described method for manufacturing the chip resistor 1, the fifth step may be performed, for example, before the second step.

(4) Characteristics of chip resistor

Next, characteristics of the chip resistor 1 including the above-described resistive paste will be described with reference to fig. 2 and tables 1 to 3. The abscissa axis of fig. 2 shows the proportion of the glass particles B with respect to the total amount of the glass particles a and B, and the ordinate axis of fig. 2 shows the TCR of the resistive element 13. Table 1 shows the composition ratio of glass particles a. Table 2 shows the composition ratio of the glass particles B. Table 3 shows the relationship among the formulation of the resistive paste, the electrical characteristics of the chip resistor including the resistive paste, and the reference intensity ratio (reference intensity ratio, RIR) of the resistive element.

TABLE 1

Component (A)	Proportion (wt.%)
		PbO	60～80
B ₂ O ₃	15～20
		ZnO	1～5
SiO ₂	5～15

TABLE 2

Component (A)	Proportion (wt.%)
		SiO ₂	2～7
Al ₂ O ₃	4～9
		B ₂ O ₃	41～50
CaO	1～5
		MgO	1～5
BaO	30～35
		Ta ₂ O ₅	3～10

TABLE 3

(unit: wt%)

As shown in Table 1, glass particles A contain lead oxide (PbO) and boron oxide (B ₂ O ₃ ) Zinc oxide (ZnO) and silicon oxide (SiO) ₂ ). In the glass particle a, the proportion of lead oxide is greater than or equal to 60 wt% and less than or equal to 80 wt%, the proportion of boron oxide is greater than or equal to 15 wt% and less than or equal to 20 wt%, the proportion of zinc oxide is greater than or equal to 1 wt% and less than or equal to 5 wt%, and the proportion of silicon oxide is greater than or equal to 5 wt% and less than or equal to 15 wt%. In the second embodiment, for example, the proportion of lead oxide is 71 wt%, the proportion of boron oxide is 16 wt%, the proportion of zinc oxide is 5 wt%, and the proportion of silicon oxide is 8 wt%.

As shown in Table 2, glass particles B contained silicon oxide, aluminum oxide, boron oxide, calcium oxide (CaO), magnesium oxide (MgO), barium oxide (BaO), and tantalum oxide (Ta ₂ O ₅ ). In the glass particles B, the proportion of silicon oxide is greater than or equal to 2 wt% and less than or equal to 7 wt%, the proportion of aluminum oxide is greater than or equal to 4 wt% and less than or equal to 9 wt%, and the proportion of boron oxide is greater than or equal to 41 wt% and less than or equal to 50 wt%. Further, in the glass particles B, the proportion of calcium oxide is greater than or equal to 1 wt% and less than or equal to 5 wt%, the proportion of magnesium oxide is greater than or equal to 1 wt% and less than or equal to 5 wt%, the proportion of barium oxide is greater than or equal to 30 wt% and less than or equal to 35 wt%, and the proportion of tantalum oxide is greater than or equal to 3 wt% and less than or equal to 10 wt%. In the second embodiment, for example, the proportion of silicon oxide is 4 wt%, the proportion of aluminum oxide is 6 wt%, the proportion of boron oxide is 46 wt%, and the proportion of calcium oxide is 3 wt%. Further, the proportion of magnesium oxide was 3 wt%, the proportion of barium oxide was 33 wt%, and the proportion of tantalum oxide was 5 wt%.

As shown in Table 3, the resistor paste in comparative example 1 contains copper-nickel alloy (CuNi), titanium silicide (TiSi ₂ ) Alumina and glass particlesSon a. In comparative example 1, copper-nickel alloy and titanium silicide reacted with each other via glass particles a, thereby producing nickel silicide (Ni ₃₁ Si ₁₂ ). In comparative example 1, the resistive element 13 included copper-nickel alloy, titanium silicide, and aluminum oxide in addition to nickel silicide. That is, in comparative example 1, as shown in table 3, nickel silicide, copper-nickel alloy, titanium silicide, and aluminum oxide were contained in the resistive element 13. In comparative example 1, TCR was-126.8 ppm and less than-50 ppm due to nickel silicide (see point P1 in FIG. 2). Further, in comparative example 1, the average resistance value of the chip resistor was 300mΩ. That is, in comparative example 1, the TCR was less than-50 ppm, and was not included in this range of greater than or equal to-50 ppm and less than or equal to +50ppm (hereinafter referred to as "predetermined range").

As shown in table 3, the resistor paste in example 1 contains copper-nickel alloy (metal particles), titanium silicide (metal silicide), aluminum oxide (insulating particles), glass particles a, and glass particles B (glass particles). That is, in example 1, the resistive paste further contains glass particles B. In comparative example 1, the proportion of glass particles a in the resistive paste was 7.76 wt%, whereas in example 1, the proportion of glass particles a in the resistive paste was 3.88 wt%, and the proportion of glass particles B in the resistive paste was 3.88 wt%. In example 1, the resistive paste contains glass particles B containing highly reactive boron oxide as a main component, and thus, the reaction of titanium silicide is promoted, and nickel silicide (Ni ₃₁ Si ₁₂ ) The amount of production of (2) increases. Thus, in embodiment 1, the TCR of the resistive element 13 is-38.0 ppm, and is included in a predetermined range (see point P2 in fig. 2). Note that, in example 1, as shown in table 3, the average resistance value of the chip resistor 1 was 350mΩ. Further, in embodiment 1, as shown in table 3, the resistive element 13 includes copper-nickel alloy, aluminum oxide, and nickel silicide.

As shown in table 3, the resistor paste in example 2 contains copper-nickel alloy (metal particles), titanium silicide (metal silicide), aluminum oxide (insulating particles), glass particles a, and glass particles B (glass particles). In example 2, the ratio of each of the glass particles a and the glass particles B in the resistive paste was changed as compared with that in example 1. Specifically, in example 2, the proportion of the glass particles a in the resistive paste was 2.16 wt%, and the proportion of the glass particles B in the resistive paste was 5.60 wt%. Therefore, in embodiment 2, the TCR of the resistive element 13 is-15.1 ppm, and thus is included in a predetermined range (see point P3 in fig. 2). Note that, in example 2, as shown in table 3, the average resistance value of the chip resistor 1 was 414mΩ. Further, in example 2, as shown in table 3, the resistive element 13 includes copper-nickel alloy, aluminum oxide, and nickel silicide.

As shown in table 3, the resistor paste in example 3 contains copper-nickel alloy (metal particles), titanium silicide (metal silicide), aluminum oxide (insulating particles), and glass particles B (glass particles). That is, in example 3, all of the glass particles a were replaced with glass particles B. In example 3, the proportion of glass particles B in the resistor paste was 7.76 wt%. In example 3, all of the glass particles a were replaced with glass particles B, thereby also activating the reaction between the copper-nickel alloy and glass particles B, and therefore, except for nickel silicide (Ni ₃₁ Si ₁₂ ) In addition to this, nickel aluminum boride (Ni ₂₀ Al ₃ B ₆ ). Therefore, in embodiment 3, the TCR of the resistive element 13 is-0.5 ppm, and is thus included within a predetermined range (see point P4 in fig. 2). Note that, in embodiment 3, the average resistance value of the chip resistor 1 is 363mΩ. Further, in example 3, as shown in table 3, the resistance element 13 contains copper-nickel alloy, aluminum oxide, nickel silicide, and nickel aluminum boride.

Here, the approximation formula of the points P2 to P4 corresponding to the above embodiments 1 to 3, respectively, is formula (1) (see the broken line a1 in fig. 2). Note that "x" in the formula (1) is a ratio of the glass particles B to the total amount of the glass particles a and B, and "y" in the formula (1) is TCR.

[ 1]

y ＝ -102.52x ² + 228.81x - 126.8 … (1)

When glass particles a and B are contained in the resistive paste at the same time as in the above-described embodiments 1 and 2, nickel silicide (nickel silicide) is generated when the resistive element 13 of the chip resistor 1 is formed from the resistive paste. Further, when the resistor paste contains only the glass particles B as in example 3, nickel aluminum boride is generated in addition to nickel silicide when the resistor element 13 of the chip resistor 1 is formed from the resistor paste.

(aspect)

The present specification discloses the following aspects.

The resistive paste of the first aspect includes metal particles, insulating particles, glass particles, and metal silicide. The metal particles comprise copper and nickel. The insulating particles include at least one of aluminum oxide, zirconium oxide, zinc oxide, or boron nitride.

This aspect enables to achieve both a high specific resistance and a low TCR of the resistive element (13).

The resistive paste of the second aspect (related to the first aspect) contains at least one of the following as the metal silicide: titanium silicide, zirconium silicide, hafnium silicide, niobium silicide, tantalum silicide, chromium silicide, tungsten silicide, molybdenum silicide, iron silicide, magnesium silicide, sodium silicide, or platinum silicide.

This aspect makes it possible to suppress the TCR reduction of the resistive element (13).

The resistive paste of the third aspect contains metal particles, insulating particles, metal silicide, and glass particles. The metal particles comprise copper and nickel. The insulating particles include at least one of aluminum oxide, zirconium oxide, zinc oxide, or boron nitride. The glass particles comprise at least boron oxide and aluminum oxide. When a resistive element (13) of a chip resistor (1) is formed from the resistive paste, a nickel compound containing nickel silicide is produced from the resistive paste.

In the resistor paste of the fourth aspect (related to the third aspect), the nickel compound further contains nickel aluminum boride.

This aspect enables further reduction of the TCR of the resistive element (13).

In the resistor paste of the fifth aspect (related to the fourth aspect), the nickel silicide is Ni ₃₁ Si ₁₂ And the nickel aluminum boride is Ni ₂₀ Al ₃ B ₆ 。

This aspect enables further reduction of the TCR of the resistive element (13).

In the resistor paste of the sixth aspect (relating to any one of the third to fifth aspects), the glass particles further contain silicon oxide, tantalum oxide, magnesium oxide, calcium oxide, and barium oxide.

This aspect enables further improvement of reactivity to metal particles and metal silicides.

In the resistor paste according to the seventh aspect (related to the sixth aspect), in the glass particles, the proportion of the boron oxide is 41 wt% or more and 50 wt% or less, the proportion of the aluminum oxide is 4 wt% or more and 9 wt% or less, the proportion of the silicon oxide is 2 wt% or more and 7 wt% or less, the proportion of the tantalum oxide is 3 wt% or less and 10 wt% or less, the proportion of the magnesium oxide is 1 wt% or more and 5 wt% or less, the proportion of the calcium oxide is 1 wt% or more and 5 wt% or less, and the proportion of the barium oxide is 30 wt% or more and 35 wt% or less.

This aspect enables the formation of nickel silicide.

In the resistor paste of the eighth aspect (relating to any one of the third to seventh aspects), the metal silicide includes titanium silicide.

This aspect enables the formation of nickel silicide.

The resistive paste of the ninth aspect (related to any one of the first to eighth aspects) further comprises an organic carrier.

This aspect enables the materials to be mixed with each other and uniformly dispersed.

The chip resistor (1) of the tenth aspect includes a resistive element (13) and a substrate (11). The resistive element (13) contains the resistive paste of any one of the first to ninth aspects as a material and is provided on the substrate (11).

In the chip resistor (1) of the eleventh aspect (related to the tenth aspect), the resistance element (13) contains nickel silicide.

The glass particles of the twelfth aspect are contained in the resistive paste of any one of the third to ninth aspects.

The constitution of the second aspect and the fourth aspect to the ninth aspect are not essential constitution of the resistive paste, and thus can be omitted accordingly.

List of reference numerals

1. Chip resistor

11. Substrate

13. Resistor element

Claims

1. A resistive paste, the resistive paste comprising:

metal particles comprising copper and nickel;

insulating particles including at least one of alumina, zirconia, zinc oxide, or boron nitride;

glass particles; and

And (3) metal silicide.

2. The resistive paste of claim 1, comprising as the metal silicide at least one of: titanium silicide, zirconium silicide, hafnium silicide, niobium silicide, tantalum silicide, chromium silicide, tungsten silicide, molybdenum silicide, iron silicide, magnesium silicide, sodium silicide, or platinum silicide.

3. A resistive paste, the resistive paste comprising:

metal particles comprising copper and nickel;

a metal silicide; and

the glass particles are used as a material for the glass particles,

the glass particles comprise at least boron oxide and aluminum oxide,

when a resistive element of a chip resistor is formed from the resistive paste, a nickel compound containing nickel silicide is produced from the resistive paste.

4. A resistive paste according to claim 3, wherein

The nickel compound further comprises nickel aluminum boride.

5. The resistive paste of claim 4, wherein

The nickel silicide is Ni ₃₁ Si ₁₂ And (2) and

the nickel aluminum boride is Ni ₂₀ Al ₃ B ₆ 。

6. The resistive paste according to any one of claims 3 to 5, wherein

The glass particles also comprise silicon oxide, tantalum oxide, magnesium oxide, calcium oxide, and barium oxide.

7. The resistive paste of claim 6, wherein

In the glass particles, the proportion of the boron oxide is 41% by weight or more and 50% by weight or less, the proportion of the aluminum oxide is 4% by weight or more and 9% by weight or less, the proportion of the silicon oxide is 2% by weight or more and 7% by weight or less, the proportion of the tantalum oxide is 3% by weight or more and 10% by weight or less, the proportion of the magnesium oxide is 1% by weight or more and 5% by weight or less, the proportion of the calcium oxide is 1% by weight or more and 5% by weight or less, and the proportion of the barium oxide is 30% by weight or more and 35% by weight or less.

8. The resistive paste according to any one of claims 3 to 7, wherein

The metal silicide includes titanium silicide.

9. The resistive paste of any one of claims 1 to 8, further comprising:

an organic carrier.

10. A chip resistor, the chip resistor comprising:

a substrate; and

a resistive element on the substrate, the resistive element comprising the resistive paste according to any one of claims 1 to 9 as a material.

11. The chip resistor of claim 10 wherein

The resistive element comprises nickel silicide.

12. Glass particles contained in the resistive paste according to any one of claims 3 to 9.