JP2004288667A - Non-linear voltage resistor porcelain composition, electronic part and multilayer chip varistor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-linear voltage resistor porcelain composition in which sintering can be sufficiently performed, in which an electrostatic capacitance can be lowered even when a circuit voltage is lowered, and which has excellent voltage load lifetime characteristics at a high temperature; and to provide an electronic part, such as a multilayer chip varistor, etc. using the composition. <P>SOLUTION: The non-linear voltage resistor porcelain composition contains a main component containing a zinc oxide, a first accessory constituent containing the oxide of a rare earth element, a second accessory constituent containing an Si oxide, and a third accessory constituent containing at least one type of oxide of Cr and Mo. A ratio of the third accessory constituent to a main constituent of 100 mol is 0 atomic %< third accessory constituent < 2 atomic % in terms of the Cr and the Mo. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００８２】
【表２】

【００８３】
【表３】

【００８４】
【表４】

【００８５】
【表５】

【００８６】
【表６】

【００８７】
【表７】

【００８８】
【表８】

評価
表１に示すように、第３副成分の添加量と電気特性の関係については、ＣｒまたはＭｏの添加量が増えるに従って、バリスタ電圧は増加していく。このとき、ＣｒまたはＭｏ添加量の多い場合を除いて、非直線性に大きな違いは認められなかった。試料１においては、高温負荷寿命試験において１００時間を待たずにショートしたのに対して、０．１原子％のＣｒを含有した試料５は、試験後もほとんど変化が認められず、Ｃｒの含有効果が分かる。試料８〜１３に示すように、Ｍｏについても同様であり、０．１原子％の添加が最も良好であることが確認できた。また、試料１４に示すように、ＣｒとＭｏを同時に含有させても同様の効果が認められた。表１に示す結果から、主成分１００モルに対する前記第３副成分の比率は、ＣｒおよびＭｏ換算で、０原子％＜第３副成分＜２原子％、好ましくは０．００５原子％≦第３副成分≦１原子％、さらに好ましくは０．０１原子％≦第３副成分≦１原子％であることが確認できた。
【００８９】
表２は、希土類元素であるＰｒの含有量と電気特性についてまとめたものである。ＣＶ積については、いずれについても問題なく小さい。しかし、Ｐｒ含有量が０．０１原子％である試料１５，２１では、バリスタ電圧が得られなかった。また、Ｐｒ含有量が１０原子％である試料２０，２６では、バリスタ電圧が急激に増大し２００Ｖを超えることが確認できた。表２に示す結果から、主成分１００モルに対する前記第１副成分の比率が、希土類元素換算で、好ましくは０．０１原子％＜第１副成分＜１０原子％、さらに好ましくは０．０５原子％≦第１副成分≦５原子％であることが確認できた。
【００９０】
表３は、Ｐｒの代わりに種々の希土類元素を含有したときの結果である。この表から、いずれの希土類元素も用いる事ができることが確認できた。
【００９１】
表４に示すように、第２副成分の添加量と電気特性の関係については、Ｓｉの添加量が増えるに従って、バリスタ電圧は増加していくが、ＣＶ積が減少していくことが確認された。試料５５に対して２原子％のＳｉを含有した試料５７は、ＣＶ積が約２５％減少し、Ｓｉの含有効果が分かる。さらに、ＣＶ積は、Ｓｉ含有量の増加とともに減少し、Ｓｉを１０原子％含有した試料５で、ＣＶ積が試料５５の半分以下となった。Ｓｉを３０原子％含有した試料６０では、非直線性が失われ抵抗体となることが確認された。表４に示す結果から、主成分１００モルに対する前記第２副成分の比率は、Ｓｉ換算で、好ましくは１原子％≦第２副成分＜３０原子％、より好ましくは２原子％≦第２副成分≦２０原子％、さらに好ましくは５原子％≦第２副成分≦２０原子％であることが確認できた。
【００９２】
表５は、Ｃｏ含有量と電気特性についてについてまとめたものであるが、ＣＶ積については、いずれについても問題なく小さい。しかし、Ｃｏ含有量が０．０５原子％である試料６７，７４では、バリスタ電圧が得られなかった。また、Ｃｏ含有量が５０原子％である試料７３，８０では、バリスタ電圧の増大と非直線性の低下が見られた。表５に示す結果から、主成分１００モルに対する該第４副成分の比率が、Ｃｏ換算で、好ましくは０．０５原子％＜第４副成分＜５０原子％、さらに好ましくは０．１原子％≦第４副成分≦３０原子％、特に好ましくは１原子％≦第４副成分≦２０原子％であることが確認できた。
【００９３】
表６は、ＩＩＩｂ族元素であるＢ、Ａｌ、ＧａおよびＩｎ含有した場合の結果を示した。Ａｌ含有量が０．０００１原子％の試料８１，９５では、バリスタ電圧が急激に増大し２００Ｖを超えた。また、Ａｌ含有量が１原子％の試料９４，１０８ではバリスタ電圧が得られなかった。さらにＡｌの代わりにＢ、ＧａおよびＩｎを用いることができ、Ｂ、Ａｌ、ＧａおよびＩｎから選ばれた２種類以上の組み合わせを用いる事ができることが確認できた。また、表６に示す結果から、主成分１００モルに対する該第５副成分の比率が、各Ｂ、Ａｌ、ＧａおよびＩｎ換算で、好ましくは０．０００１原子％＜第５副成分＜１原子％、さらに好ましくは０．０００５原子％≦第５副成分≦０．５原子％であることが確認できた。
【００９４】
表７は、アルカリ金属としてＮａ、Ｋ、Ｒｂ、Ｃｓを含有した場合の結果を示した。Ｋ含有量が０．００５原子％である試料１０９，１２４では、抵抗が低くバリスタ電圧が得られなかった。また、Ｋ含有量が５原子％の試料１２３，１３８では、試料が溶融状態となり電気特性を測定できなかった。さらにＫの代わりに他のアルカリ金属であるＮａ、Ｒｂ、Ｃｓを用いても構わないし、２種類以上のアルカリ金属を組み合わせて添加しても構わないことが確認できた。表７に示す結果から、主成分１００モルに対する該第６副成分の比率が、各Ｎａ、Ｋ、ＲｂおよびＣｓ換算で、好ましくは０．００５原子％＜第６副成分＜５原子％、さらに好ましくは０．０５原子％≦第６副成分≦２原子％であることが確認できた。
【００９５】
表８は、アルカリ土類金属としてＭｇ、Ｃａ、ＳｒおよびＢａを含有した場合の結果を示した。Ｃａ含有量が０．０５原子％の試料１３９，１４６では、非直線性が小さくなり、また、５原子％の試料１４５，１５２ではバリスタ電圧が急増した。また、Ｍｇ、ＳｒおよびＢａを用いた場合も同様の結果が得られ、さらにこれらを併用しても含有の効果が得られることが確認できた。表８に示す結果から、主成分１００モルに対する該第７副成分の比率が、各Ｍｇ、Ｃａ、ＳｒおよびＢａ換算で、好ましくは０．０５原子％＜第７副成分＜５原子％、さらに好ましくは０．１原子％≦第７副成分≦３原子％であることが確認できた。
【００９６】
実施例２
本実施例では、本発明に係る電圧非直線性抵抗体磁器組成物そのものの特性を評価した。
【００９７】
表１の試料５に示す組成の粉体（電圧非直線性抵抗体磁器組成物の材料）に、バインダとしてのポリビニルアルコールを添加して、顆粒状になるようにバインダと電圧非直線性抵抗体磁器組成物材料とを混合した。次に、この顆粒状の電圧非直線性抵抗体磁器組成物材料をプレス成形し、外径φ１６ｍｍ、厚み１．２ｍｍの円板状予備成形体を得た。
【００９８】
次に、この得られた予備成形体を、３５０℃で２時間、脱バインダーを行った後、１２００℃で２時間、大気中で焼成し、外径φ１４ｍｍ、厚みが１ｍｍの円板状半導体焼結体を得た。
【００９９】
次に、この円板状半導体焼結体の両面に、Ａｇを焼き付けることでφ１１．５ｍｍの電極を形成して、本発明の電圧非直線性抵抗体磁器組成物の試料としての円板状試料を得た。
【０１００】
得られた円盤状試料を用いて、実施例１と同様に、バリスタ電圧、非直線係数、ＣＶ積および高温負荷寿命特性を測定した。その結果、実施例１と同様の効果が得られることが確認できた。
【０１０１】
【発明の効果】
以上説明してきたように、本発明によれば、焼結を十分に行うことが可能であり、かつ回路電圧を低下させても、静電容量を低下させることができ、しかも高温下での電圧負荷寿命特性に優れた電圧非直線性抵抗体磁器組成物、および該組成物を用いた積層チップバリスタなどの電子部品を提供することができる。
【図面の簡単な説明】
【図１】図１は本発明の一実施形態に係る積層チップバリスタの断面図である。
【符号の説明】
２… 積層チップバリスタ
４，６… 内部電極層
８… 層間電圧非直線性抵抗体層
８ａ… 外側保護層
１０… 素子本体
１２，１４… 外部端子電極[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides, for example, a voltage non-linear resistor ceramic composition used as a voltage non-linear resistor layer of a multilayer chip varistor, and an electronic device using the voltage non-linear resistor composition as a voltage non-linear resistor layer. Related to parts.
[0002]
[Prior art]
A varistor as an example of an electronic component having a voltage non-linear resistor layer is used to absorb or remove an external surge (an abnormal voltage) such as static electricity or noise.
[0003]
With the recent increase in digital signal speed and communication speed, there has been a demand for a varistor having a low capacitance and little influence on the signal.
[0004]
The capacitance is C = ε₀ε_r(S / d) Expression 1 C is the capacitance, ε₀Is the dielectric constant of vacuum, ε_rIs the relative permittivity, S is the area of the counter electrode at which the capacitance appears, and d is the thickness between the counter electrodes. In the case of a zinc oxide varistor, care must be taken in handling the thickness d. Zinc oxide varistors exhibit characteristics due to crystal grain boundaries. That is, there is a large difference between the resistance at the grain boundary and the resistance in the grain in the steady state, and the resistance at the grain boundary is much larger than that in the grain. Therefore, in a steady state not exceeding the breakdown voltage (rising voltage), almost all of the applied electric field is applied to the grain boundaries. Therefore, the above-mentioned thickness d must take this point into consideration.
[0005]
The thickness d is represented by d = n · 2W... n is the number of grain boundaries parallel to the counter electrode, and 2W is the depletion layer width of one grain boundary.
[0006]
The varistor voltage V_1mAAnd the number of grain boundaries n, n = V_1mA/ Φ... Equation 3 holds. φ is the barrier height of the grain boundary and is a value representing the varistor voltage per grain boundary.
[0007]
Here, when Expression 2 and Expression 3 are substituted into Expression 1, and then transformed, C · V_1mA= Ε₀ε_r(Φ · S / 2W) Expression 4 When φ and 2W have appropriate varistor characteristics, they take a certain value (for example, φ = 0.8 eV 2W = about 30 nm). Therefore, when the electrode area S is constant, Expression 4 is constant. Conversely, to reduce the capacitance while maintaining the appropriate varistor characteristics, it is effective to reduce the electrode area S.
[0008]
Conventionally, as a method of reducing S, a method of directly reducing the area of a counter electrode of a varistor has been proposed (see Patent Document 1). However, if the area of the counter electrode is simply reduced, the energy resistance and the surge resistance are reduced as a result, and the reliability of the device is reduced. The varistor converts electrical energy such as surge from the outside into thermal energy and absorbs it. In order to minimize the reduction of the energy resistance and the surge resistance and to reduce the capacitance, it is considered that the fine structure of the ceramic should be controlled.
[0009]
That is, the area of the varistor crystal grain boundary for developing the varistor capacitance between the electrodes is reduced by making the area of the counter electrode the same as the conventional one, and the second phase other than zinc oxide is introduced to control the volume ratio. It is. At this time, it is preferable to make the distribution of the second phase uniform, disperse the heat generated at the crystal grain boundary when absorbing the surge to the second phase, and prevent the temperature of the crystal boundary from rising too much.
[0010]
Further, with the recent reduction in circuit voltage, it is desired to further reduce the varistor voltage (V). Since the electrical characteristics of the varistor appear at the crystal grain boundaries, it is necessary to reduce the number of crystal grain boundaries existing between the counter electrodes in order to reduce the varistor voltage. As a technique for lowering the varistor voltage, a multilayer varistor in which an internal electrode is embedded in a sintered body made of a semiconductor ceramic containing zinc oxide as a main component and an oxide of Pr as a rare earth element is proposed. (See Patent Document 2). In this varistor, the varistor voltage can be made relatively low, and a relatively inexpensive Ag-Pd alloy can be used for the internal electrode without using expensive Pt.
[0011]
However, if the number of crystal grain boundaries existing between the counter electrodes is simply reduced in order to lower the varistor voltage, the number of crystal grain boundaries in series decreases, which leads to an increase in capacitance. There is an inconvenience.
[0012]
In order to reduce the capacitance while maintaining the varistor characteristics, a zinc oxide, an oxide of Pr, an oxide of Co, an oxide of Al, an oxide of K, and an oxide of lithium are added to zinc oxide. (Patent Document 3) has been proposed. However, even with the technique described in this publication, there is a problem in balancing the reduction in varistor voltage and the reduction in capacitance.
[0013]
Therefore, the present applicant has previously proposed a technique for balancing the reduction in the varistor voltage and the reduction in the capacitance. After that, a new problem was found that it is desirable to improve the varistor characteristics even in a voltage load life test at a high temperature.
[0014]
[Patent Document 1] JP-A-6-13260
[Patent Document 2] JP-A-5-283209
[Patent Document 3] JP-A-2000-68112
[Patent Document 4] Japanese Patent Application No. 2002-184640
[Patent Document 5] Japanese Patent Application No. 2002-31272
[Problems to be solved by the invention]
An object of the present invention is to provide a voltage capable of sufficiently performing sintering, and capable of reducing the capacitance even when the circuit voltage is reduced, and having excellent voltage load life characteristics at high temperatures. An object of the present invention is to provide a nonlinear resistor porcelain composition and an electronic component such as a multilayer chip varistor using the composition.
[0015]
[Means for Solving the Problems]
To achieve the above object, according to the present invention,
A main component containing zinc oxide;
A first subcomponent containing a rare earth element oxide;
A second subcomponent containing an oxide of Si;
A voltage non-linear resistor porcelain composition comprising: a third subcomponent containing at least one oxide of Cr and Mo;
A voltage non-linear resistor ceramic composition is provided in which the ratio of the third subcomponent to 100 mol of the main component is 0 atomic% <third subcomponent <2 atomic% in terms of Cr and Mo.
[0016]
According to the present invention,
An electronic component having a voltage non-linear resistor layer,
The voltage non-linear resistor layer is composed of a voltage non-linear resistor ceramic composition,
The voltage nonlinear resistor porcelain composition,
A main component containing zinc oxide;
A first subcomponent containing a rare earth element oxide;
A second subcomponent containing an oxide of Si;
A third subcomponent containing at least one oxide of Cr and Mo,
An electronic component is provided in which the ratio of the third subcomponent with respect to 100 mol of the main component is 0 atomic% <third subcomponent <2 atomic% in terms of Cr and Mo.
[0017]
The electronic component according to the present invention is not particularly limited, and examples thereof include a multilayer chip varistor, a disk varistor, and a varistor composite element.
[0018]
According to the present invention,
A multilayer chip varistor having a voltage non-linear resistor layer,
The voltage non-linear resistor layer is composed of a voltage non-linear resistor ceramic composition,
The voltage nonlinear resistor porcelain composition,
A main component containing zinc oxide;
A first subcomponent containing a rare earth element oxide;
A second subcomponent containing an oxide of Si;
A third subcomponent containing at least one oxide of Cr and Mo,
There is provided a multilayer chip varistor in which a ratio of the third subcomponent to 100 mol of the main component is 0 atomic% <third subcomponent <2 atomic% in terms of Cr and Mo.
[0019]
Preferably, the oxide of the rare earth element contained in the first subcomponent is selected from Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. At least one oxide.
[0020]
Preferably, the ratio of the first subcomponent with respect to 100 mol of the main component is 0.01 atomic% <first subcomponent <10 atomic% in terms of rare earth element.
[0021]
Preferably, the ratio of the second subcomponent with respect to 100 mol of the main component is 1 atomic% ≦ second subcomponent <30 atomic% in terms of Si.
[0022]
Preferably, the composition further includes a fourth subcomponent containing an oxide of Co, wherein the ratio of the fourth subcomponent to 100 mol of the main component is 0.05 atom% <fourth sub component <50 atom in terms of Co. %.
[0023]
Preferably, the semiconductor device further includes a fifth subcomponent containing at least one oxide selected from B, Al, Ga, and In, and the ratio of the fifth subcomponent to 100 mol of the main component is set to B, Al, 0.0001 atomic% <fifth subcomponent <1 atomic% in terms of Ga and In.
[0024]
Preferably, it further has a sixth subcomponent containing at least one oxide selected from Na, K, Rb and Cs, and the ratio of the sixth subcomponent to 100 mol of the main component is Na, K, In terms of Rb and Cs, 0.005 atomic% <sixth subcomponent <5 atomic%.
[0025]
Preferably, it further has a seventh subcomponent containing at least one oxide selected from Mg, Ca, Sr and Ba, and the ratio of the seventh subcomponent to 100 mol of the main component is such that each of Mg, Ca, In terms of Sr and Ba, 0.05 atomic% <seventh subcomponent <5 atomic%.
[0026]
In the present invention, the varistor voltage refers to a voltage when a current of 1 mA flows. The varistor characteristic (voltage non-linearity) refers to a phenomenon in which a current flowing through an element increases non-linearly when a gradually increasing voltage is applied to an electronic component.
[0027]
[Action]
In the present invention, a third subcomponent containing an oxide of Cr and / or Mo is contained in a specific amount with respect to the main component containing zinc oxide. For this reason, the uniformity of the particle diameter of the zinc oxide crystal particles contained in the main component can be improved. By improving the uniformity of the particle diameter of the zinc oxide crystal particles, the applied voltage during the high-temperature load test is uniformly applied to the crystal grain boundaries, and as a result, the high-temperature load life is improved (for example, a change in the varistor voltage). Rate ((△ V_1mA) / V_1mA) Can be within ± 50%, preferably within ± 10%).
[0028]
Further, in the present invention, the developed capacitance can be reduced (for example, the counter electrode area is 1 cm).²The CV product represented by the product of the capacitance C of 1 MHz and the varistor voltage V can be made 290,000 or less, preferably 270,000 or less, and more preferably 200,000 or less.
[0029]
Further, in the present invention, Bi that easily reacts with Pd is not contained in the voltage non-linear resistor ceramic composition, so that Pd can be used as the internal electrode, and the ceramic can be sufficiently sintered.
[0030]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described based on embodiments shown in the drawings. put it here,
FIG. 1 is a sectional view of a multilayer chip varistor according to one embodiment of the present invention.
[0031]
Multilayer chip varistor
As shown in FIG. 1, a multilayer chip varistor 2 as an example of an electronic component has an element body 10 having a configuration in which internal electrode layers 4 and 6 and an interlayer voltage non-linear resistor layer 8 are stacked. At both ends of the element body 10, a pair of external terminal electrodes 12, 14 that are electrically connected to the internal electrode layers 4, 6 disposed inside the element body 10 are formed. Although the shape of the element body 10 is not particularly limited, it is usually a rectangular parallelepiped. The size is not particularly limited, and may be an appropriate size depending on the application. Usually, the length (0.6 to 5.6 mm) × the width (0.3 to 5.0 mm) × the thickness ( 0.3 to 1.9 mm).
[0032]
The internal electrode layers 4 and 6 are laminated such that each end face is exposed on the surface of two opposing end portions of the element body 10. The pair of external terminal electrodes 12 and 14 are formed at both ends of the element body 10 and connected to the exposed end faces of the internal electrode layers 4 and 6, respectively, to form a circuit.
[0033]
In the element body 10, outer protective layers 8 a are disposed at both outer ends in the laminating direction of the internal electrode layers 4 and 6 and the interlayer voltage non-linear resistor layer 8, thereby protecting the inside of the element body 10. ing. The material of the outer protective layer 8a may be the same as or different from the material of the interlayer voltage non-linear resistor layer 8. The thickness of the outer protective layer 8a is, for example, about 100 to 500 μm.
[0034]
Internal electrode layer
The conductive material contained in the internal electrode layers 4 and 6 is not particularly limited, but is preferably made of Pd or an Ag-Pd alloy. The Pd content in the alloy is preferably at least 95% by weight. The thickness of the internal electrode layers 4 and 6 may be appropriately determined according to the application, but is usually about 0.5 to 5 μm.
[0035]
External terminal electrode
The conductive material contained in the external terminal electrodes 12 and 14 is not particularly limited, but usually Ag or an Ag-Pd alloy is used. The thickness of the external terminal electrodes 12 and 14 may be appropriately determined depending on the application, but is usually about 10 to 50 μm.
[0036]
Interlayer voltage nonlinear resistor layer
The interlayer voltage non-linear resistor layer 8 is composed of the voltage non-linear resistor ceramic composition of the present invention.
[0037]
The voltage non-linear resistor ceramic composition of the present invention has a main component containing zinc oxide. The main component containing zinc oxide acts as a substance that exhibits excellent voltage non-linearity in voltage-current characteristics and large surge withstand capability.
[0038]
The voltage non-linear resistor ceramic composition of the present invention further has a first subcomponent containing an oxide of a rare earth element. The first subcomponent has a property that it does not easily react with the conductive material forming the internal electrode layers 4 and 6, and also acts as a substance that increases the rate of diffusion of oxygen to crystal grain boundaries. When this is added, it does not easily react with the conductive material constituting the internal electrode layers 4 and 6, so that the sintered body can be sufficiently sintered.
Oxides of rare earth elements contained in the first subcomponent are from Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, excluding Sc and Pm. It is preferably at least one selected oxide, and more preferably contains at least Pr oxide.
The ratio of the first subcomponent with respect to 100 mol of the main component is not particularly limited, but is preferably 0.01 atom% <first subcomponent <10 atom%, more preferably 0.05 atom% ≦ 1 subcomponent ≦ 5 atomic%. By setting the ratio of the first subcomponent in a predetermined range, the composition can be maintained in a semiconducting state, and the rate of diffusion of oxygen to crystal grain boundaries can be increased. If the ratio of the first subcomponent is too low, the voltage non-linearity tends to be hardly obtained, and if the ratio is too high, the varistor voltage tends to increase rapidly.
[0039]
The voltage nonlinear resistor porcelain composition of the present invention further includes a second subcomponent containing an oxide of Si. This second subcomponent acts as a substance that reduces the CV product (product of capacitance C and varistor voltage V) of the composition. By adding this, the capacitance can be reduced even if the circuit voltage is reduced.
The ratio of the second subcomponent with respect to 100 mol of the main component is preferably 1 atomic% ≦ second subcomponent <30 atomic%, more preferably 2 atomic% ≦ second subcomponent ≦ 20 atomic%, more preferably, in terms of Si. Is 5 atomic% ≦ second subcomponent ≦ 20 atomic%. If the ratio of the second subcomponent is too high, the varistor voltage is too high, and sintering tends to be impossible. If the ratio of the second subcomponent is too low, a decrease in the CV product, that is, a decrease in capacitance can be expected. Instead, the effect of balancing the reduction in varistor voltage and the reduction in capacitance tends to be small.
[0040]
The voltage nonlinear resistor porcelain composition of the present invention further has a third subcomponent containing at least one oxide of Cr and Mo. This third subcomponent acts as a substance that improves the high temperature load life characteristics of the composition.
A feature of the present invention is that a predetermined amount of the third subcomponent is added together with the second subcomponent to 100 mol of the main component containing zinc oxide. By adding such a third subcomponent in a predetermined amount, the capacitance can be reduced even if the circuit voltage is reduced, and the high-temperature load life characteristics can be improved.
Specifically, the ratio of the third subcomponent with respect to 100 mol of the main component is 0 atomic% <third subcomponent <2 atomic%, preferably 0.005 atomic% ≦ third subcomponent in terms of Cr and Mo. Component ≦ 1 atomic%, more preferably 0.01 atomic% ≦ third subcomponent ≦ 1 atomic%. In the present invention, the effect of improving the characteristics of the voltage load life at high temperatures can be obtained by adding the third subcomponent. However, if the ratio of the third subcomponent is too large, the effect of improving the characteristics is small. Tend to be.
[0041]
The voltage nonlinear resistor porcelain composition according to the present invention preferably further includes a fourth subcomponent containing an oxide of Co. This fourth subcomponent acts as an acceptor (electron capture agent) and acts as a substance that maintains voltage non-linearity.
The ratio of the fourth subcomponent with respect to 100 mol of the main component is preferably 0.05 atomic% <the fourth subcomponent <50 atomic%, more preferably 0.1 atomic% ≦ the fourth subcomponent ≦ 30 in terms of Co. Atomic%, particularly preferably 1 atomic% ≦ fourth subcomponent ≦ 20 atomic%. If the ratio of the fourth subcomponent is too low, it tends to be difficult to obtain varistor characteristics. If it is too high, the varistor voltage increases and the voltage non-linearity tends to decrease.
[0042]
The voltage non-linear resistor ceramic composition according to the present invention preferably further includes a fifth subcomponent containing at least one oxide selected from B, Al, Ga and In. The fifth subcomponent acts as a donor for controlling the amount of electrons to the main component including zinc oxide, increases the amount of electrons to the main component, and functions as a substance that turns the composition into a semiconductor.
The ratio of the fifth subcomponent with respect to 100 mol of the main component is preferably 0.0001 atomic% <fifth subcomponent <1 atomic%, more preferably 0.0005 atomic%, in terms of B, Al, Ga and In. .Ltoreq.fifth subcomponent.ltoreq.0.5 at%. If the ratio of the fifth subcomponent is too low, the varistor voltage tends to increase. If the ratio is too high, the resistance tends to be low, and it tends to be difficult to obtain varistor characteristics.
[0043]
The voltage nonlinear resistor porcelain composition according to the present invention preferably further includes a sixth subcomponent containing at least one oxide selected from Na, K, Rb and Cs. This sixth subcomponent acts as a substance that improves the voltage nonlinearity of the composition. The ratio of the sixth subcomponent with respect to 100 mol of the main component is preferably 0.005 atomic% <sixth subcomponent <5 atomic%, more preferably 0.05 atomic%, in terms of Na, K, Rb and Cs. <6th subcomponent <2 atomic%. If the ratio of the sixth subcomponent is too low, the resistance tends to be low and a varistor voltage tends not to be obtained. If the ratio is too high, the melting point of the ceramic tends to decrease, and the ceramic tends to melt during firing.
[0044]
The voltage non-linear resistor ceramic composition according to the present invention preferably further includes a seventh subcomponent containing at least one oxide selected from Mg, Ca, Sr, and Ba. This seventh subcomponent acts as a substance that improves voltage non-linearity. The ratio of the seventh subcomponent with respect to 100 mol of the main component is preferably 0.05 atom% <seventh sub component <5 atom%, more preferably 0 atom%, in terms of Mg, Ca, Sr and Ba in the oxide. .1 atomic% ≦ seventh subcomponent ≦ 3 atomic%. If the ratio of the seventh subcomponent is too low, the voltage non-linearity tends to decrease, and if the ratio is too high, the varistor voltage tends to increase.
[0045]
Various conditions such as the number of layers and the thickness of the interlayer voltage non-linear resistor layer 8 may be appropriately determined according to the purpose and application. In the present embodiment, the thickness of the interlayer voltage non-linear resistor layer 8 is, for example, about 5 to 100 μm.
[0046]
In the interlayer voltage nonlinear resistor layer 8 according to the present embodiment, the nonlinear coefficient (α) is preferably 8 or more, more preferably 10 or more, and particularly preferably 15 or more.
Further, in the interlayer voltage non-linear resistor layer 8, when the capacitance is measured at a reference temperature of 25 ° C., a measurement frequency of 1 MHz, and an input signal level (measurement voltage) of 1 Vrms, a CV product (capacitance C and varistor) is obtained. Product of the voltage V) and the counter electrode area is 1 cm²In this case, it is usually 290,000 or less, preferably 270,000 or less, more preferably 200,000 or less.
Furthermore, in the interlayer voltage non-linear resistor layer 8, the change rate of the varistor voltage ((△ V_1mA) / V_1mA) Is usually within ± 50%, preferably within ± 10%.
[0047]
Manufacturing method of multilayer chip varistor
Next, an example of a method for manufacturing the multilayer chip varistor 2 according to the present embodiment will be described.
[0048]
In the present embodiment, a green chip is produced by a normal printing method or sheet method using a paste, fired, and then printed or transferred to an external terminal electrode and fired. Hereinafter, the manufacturing method will be specifically described.
[0049]
First, a paste for a voltage non-linear resistor layer, a paste for an internal electrode layer, and a paste for an external terminal electrode are prepared. The interlayer voltage non-linear resistor layer 8 and the outer protective layer 8a shown in FIG. 1 can be formed using the voltage non-linear resistor layer paste.
[0050]
The voltage nonlinear resistor layer paste may be an organic paint obtained by kneading a voltage nonlinear resistor ceramic composition raw material and an organic vehicle, or may be an aqueous paint.
[0051]
In the voltage non-linear resistor ceramic composition raw material, according to the composition of the above-described voltage non-linear resistor ceramic composition of the present invention, a raw material forming a main component and a raw material forming each subcomponent are included. Used.
[0052]
As a raw material constituting the main component, an oxide of Zn and / or a compound which becomes an oxide by firing is used. As a raw material constituting the first subcomponent, an oxide of a rare earth element and / or a compound which becomes an oxide by firing is used. As a raw material constituting the second subcomponent, an oxide of Si and / or a compound which becomes an oxide by firing is used. As a raw material constituting the third subcomponent, oxides of Cr and Mo and / or compounds which become these oxides by firing are used. As a raw material constituting the fourth subcomponent, an oxide of Co and / or a compound which becomes an oxide by firing is used. As a raw material constituting the fifth subcomponent, one or more single oxides or composite oxides selected from oxides of B, Al, Ga, and In and / or compounds that become these oxides after firing are used. Can be As a raw material constituting the sixth subcomponent, one or more single oxides or composite oxides selected from oxides of Na, K, Rb, and Cs and / or compounds that become these oxides after firing are used. Can be As a raw material constituting the seventh subcomponent, one or more single oxides or composite oxides selected from oxides of Mg, Ca, Sr, and Ba and / or compounds that become these oxides after firing are used. Can be
In addition, as a compound which turns into an oxide by baking, a hydroxide, a carbonate, a nitrate, an oxalate, an organometallic compound, etc. are illustrated, for example. Of course, an oxide and a compound that becomes an oxide by firing may be used in combination. The content of each compound in the raw material of the voltage non-linear resistor ceramic composition may be determined so that the composition of the voltage non-linear resistor ceramic composition after firing is obtained. These raw material powders usually have an average particle diameter of about 0.3 to 2 μm.
[0053]
The organic vehicle is obtained by dissolving a binder in an organic solvent, and the binder used for the organic vehicle is not particularly limited, and may be appropriately selected from ordinary various binders such as ethyl cellulose and polyvinyl butyral. Also, the organic solvent used at this time is not particularly limited, and may be appropriately selected from organic solvents such as terpineol, butyl carbitol, acetone, and toluene according to a method to be used such as a printing method and a sheet method.
[0054]
In addition, the water-based paint is obtained by dissolving a water-soluble binder, a dispersant, and the like in water, and the water-based binder is not particularly limited, and is appropriately selected from polyvinyl alcohol, cellulose, a water-soluble acrylic resin, an emulsion, and the like. do it.
[0055]
The internal electrode layer paste is prepared by kneading the above-mentioned various conductive materials or various oxides, organometallic compounds, resinates, etc. which become the above-mentioned conductive materials after firing, and the above-mentioned organic vehicle. Also, the paste for the external terminal electrodes is prepared in the same manner as the paste for the internal electrode layers.
[0056]
The content of the organic vehicle in each paste is not particularly limited, and may be a usual content, for example, about 1 to 5% by weight of a binder and about 10 to 50% by weight of a solvent. Each paste may contain additives selected from various dispersants, plasticizers, dielectrics, insulators, and the like, as necessary.
[0057]
When the printing method is used, the voltage non-linear resistor layer paste is printed a plurality of times on a substrate such as polyethylene terephthalate with a predetermined thickness to form the outer protective layer 8a shown in FIG. Next, the internal electrode layer paste is printed in a predetermined pattern on the outer protective layer 8a to form the internal electrode layer 4 in a green state. Next, on the internal electrode layer 4, the voltage non-linear resistor layer paste is printed a plurality of times with a predetermined thickness in the same manner as described above to form the interlayer voltage non-linear resistor layer 8 shown in FIG. . Next, an internal electrode layer paste is printed on the interlayer voltage non-linear resistor layer 8 in a predetermined pattern to form the internal electrode layer 6. The internal electrode layers 4 and 6 are printed so as to be exposed on different end surfaces facing each other. Lastly, the voltage non-linear resistor layer paste is printed a plurality of times with a predetermined thickness on the internal electrode layer 6 in the same manner as described above to form the outer protective layer 8a shown in FIG. Then, it is pressurized and pressed while heating, and cut into a predetermined shape to obtain a green chip.
[0058]
When the sheet method is used, a green sheet is formed using a voltage non-linear resistor layer paste, and then a predetermined number of the green sheets are laminated to form an outer protective layer 8a shown in FIG. Next, the internal electrode layer paste is printed in a predetermined pattern on the outer protective layer 8a to form the internal electrode layer 4 in a green state. Similarly, the internal electrode layer 6 is formed on another outer protective layer 8a shown in FIG. These are sandwiched between the interlayer voltage non-linear resistance layers 8 shown in FIG. 1 formed by laminating a predetermined number of green sheets, and the internal electrode layers 4 and 6 are opposed to each other on different end surfaces. The chips are stacked so as to be exposed, pressurized and pressed while heating, and cut into a predetermined shape to obtain a green chip.
[0059]
Next, the green chip is subjected to binder removal processing and firing to produce a sintered body (element body 10).
[0060]
The binder removal processing may be performed under normal conditions. For example, in an air atmosphere, the temperature raising rate is about 5 to 300 ° C./hour, the holding temperature is about 180 to 400 ° C., and the temperature holding time is about 0.5 to 24 hours.
[0061]
The firing of the green chips may be performed under normal conditions. For example, in an air atmosphere, the heating rate is about 50 to 500 ° C./hour, the holding temperature is about 1000 to 1400 ° C., the temperature holding time is about 0.5 to 8 hours, and the cooling rate is about 50 to 500 ° C./hour. I do. If the holding temperature is too low, the densification becomes insufficient, and if the holding temperature is too high, the electrodes tend to break due to abnormal sintering of the internal electrodes.
[0062]
The obtained sintered body (element main body 10) is subjected to end surface polishing by, for example, barrel polishing or sand blasting, and the external terminal electrode paste is printed or transferred and baked to form external terminal electrodes 12, 14. The firing conditions for the external terminal electrode paste are preferably, for example, about 600 minutes to about 900 ° C. for about 10 minutes to 1 hour in an air atmosphere.
[0063]
The multilayer chip varistor 2 of the present embodiment manufactured as described above is used for absorbing or removing external surges (abnormal voltage) such as static electricity, noise, and the like.
[0064]
Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments at all, and it is needless to say that the present invention can be implemented in various modes without departing from the gist of the present invention. .
[0065]
For example, in the embodiment described above, the multilayer chip varistor is exemplified as the electronic component according to the present invention. However, the electronic component according to the present invention is not limited to the multilayer chip varistor, and the voltage non-linear resistor ceramic having the above composition is used. Any material may be used as long as it has a voltage non-linear resistor layer composed of a composition.
[0066]
Further, as shown in FIG. 1, the present invention is not limited to a multilayer chip varistor having only one pair of internal electrode layers. Although FIG. 1 shows only one pair of internal electrode layers, a plurality of pairs of internal electrodes may be laminated, or a laminated chip varistor in which many internal electrodes are laminated.
[0067]
【Example】
Hereinafter, the present invention will be described based on more detailed examples, but the present invention is not limited to these examples.
[0068]
Example 1
In this example, the multilayer chip varistor shown in FIG. 1 was manufactured, and its characteristics were evaluated.
[0069]
First, a main component material (ZnO) and first to seventh subcomponent materials were prepared in order to produce a material for a voltage non-linear resistor ceramic composition constituting a varistor layer. As the raw materials, oxides, carbonates, carbonate hydrates, and the like were used.
[0070]
Next, these raw materials were blended so that the composition after firing was as shown in the following tables with respect to 100 mol of ZnO as a main component, and an organic binder, an organic solvent, and an organic plasticizer were added. In addition, the mixture was wet-mixed with a ball mill for about 20 hours to prepare a slurry.
[0071]
A green sheet having a thickness of 30 μm was prepared from the slurry by a doctor blade method on a PET (polyethylene terephthalate) base film, and the desired green sheet was screen-printed using a palladium paste using a palladium paste. Printing is performed to obtain a shape, and drying is performed to form the internal electrode 4 illustrated in FIG. Next, the internal electrodes 6 shown in FIG. 1 are formed in the same manner.
[0072]
Further, the outer protective layer 8a as the outermost layer was formed by stacking a plurality of green sheets having the same composition.
[0073]
Thereafter, these were heated and pressed, and then cut into a predetermined chip shape to obtain a green chip.
[0074]
After debinding the green chip at 350 ° C. for 2 hours, the green chip was fired at 1200 ° C. for 2 hours in air to obtain a sintered body to be a laminated chip varistor element.
[0075]
Next, an electrode paste mainly composed of Ag was applied to both ends of the obtained sintered body and baked at 800 ° C. to form terminal electrodes 12 and 14. Thus, a multilayer chip varistor having the configuration shown in the sectional view of FIG. 1 was obtained. The obtained multilayer chip varistor has an overlapping area of the internal electrodes of 0.05 mm.²Met.
[0076]
Using the obtained multilayer chip varistor sample, the varistor voltage, the nonlinear coefficient, the CV product and the high temperature load life characteristic were measured.
Varistor voltage (V_1mA)) Connect the multilayer chip varistor sample to a DC constant current power supply, measure the voltage acting between both electrodes of the multilayer chip varistor sample with a voltmeter, and read the current flowing through the multilayer chip varistor sample with an ammeter. Determined by Specifically, when the current flowing through the multilayer chip varistor sample was 1 mA, the voltage acting between the electrodes of the multilayer chip varistor sample was read by a voltmeter, and the value was defined as the varistor voltage. The unit was V.
[0077]
The nonlinear coefficient (α) indicates the relationship between the voltage and the current applied between the electrodes of the multilayer chip varistor sample when the current flowing through the multilayer chip varistor sample changes from 1 mA to 10 mA, and was calculated from the following equation.
[0078]
α = log (I₁₀/ I₁) / Log (V10 / V1) = 1 / log (V10 / V1)
V10 is the value of I₁₀= Varier voltage when a current of 10 mA flows, and V1 is I₁= 1 means a varistor voltage when a current of 1 mA flows. The larger the nonlinear coefficient α, the better the varistor characteristics.
[0079]
The CV product was measured for a multilayer chip varistor sample at a reference temperature of 25 ° C. using a digital LCR meter (HP 4284A) at a frequency of 1 MHz and an input signal level (measurement voltage) of 1 Vrms. ) (Unit is pF) and varistor voltage V_1mAAnd the product.
[0080]
High temperature load life characteristics (varistor voltage change: (△ V_1mA) / V_1mA) Is to solder a multilayer chip varistor sample onto a substrate and apply a varistor voltage (V_1mA) Was measured and set as an initial value, and then 0.7 times the varistor voltage was applied at 85 ° C. for 100 hours, and then the varistor voltage (V) was again measured at room temperature._1mA) Was measured and calculated from the following formula (unit is%).
｛(△ V_1mA) / V_1mA｝ = ｛(V_1mA＠_100h-V_1mA＠_0h) / V_1mA＠_0h｝ × 100
The results are shown in the following tables.
[0081]
[Table 1]

[0082]
[Table 2]

[0083]
[Table 3]

[0084]
[Table 4]

[0085]
[Table 5]

[0086]
[Table 6]

[0087]
[Table 7]

[0088]
[Table 8]

Evaluation
As shown in Table 1, as for the relationship between the addition amount of the third subcomponent and the electrical characteristics, the varistor voltage increases as the addition amount of Cr or Mo increases. At this time, no significant difference was found in the non-linearity except for the case where the added amount of Cr or Mo was large. Sample 1 was short-circuited without waiting for 100 hours in the high-temperature load life test, whereas Sample 5 containing 0.1 atomic% of Cr showed almost no change even after the test. You can see the effect. As shown in Samples 8 to 13, the same was true for Mo, and it was confirmed that the addition of 0.1 atomic% was the best. Further, as shown in Sample 14, the same effect was observed when Cr and Mo were simultaneously contained. From the results shown in Table 1, the ratio of the third subcomponent to 100 mol of the main component is 0 atomic% <third subcomponent <2 atomic%, preferably 0.005 atomic% ≦ third in terms of Cr and Mo. It was confirmed that the sub-component ≦ 1 at%, more preferably 0.01 at% ≦ the third sub-component ≦ 1 at%.
[0089]
Table 2 summarizes the content and electrical properties of Pr, a rare earth element. The CV product is small without any problem. However, in Samples 15 and 21 in which the Pr content was 0.01 atomic%, no varistor voltage was obtained. Further, in samples 20 and 26 having a Pr content of 10 atomic%, it was confirmed that the varistor voltage rapidly increased and exceeded 200 V. From the results shown in Table 2, the ratio of the first subcomponent with respect to 100 moles of the main component is preferably 0.01 atom% <first subcomponent <10 atom%, more preferably 0.05 atom, in terms of rare earth element. % ≦ first subcomponent ≦ 5 at%.
[0090]
Table 3 shows the results when various rare earth elements were contained instead of Pr. From this table, it was confirmed that any of the rare earth elements could be used.
[0091]
As shown in Table 4, with respect to the relationship between the added amount of the second subcomponent and the electrical characteristics, it was confirmed that as the added amount of Si increased, the varistor voltage increased, but the CV product decreased. Was. In the sample 57 containing 2 atomic% of Si with respect to the sample 55, the CV product is reduced by about 25%, and the effect of containing Si is understood. Further, the CV product decreased with an increase in the Si content, and the CV product of Sample 5 containing 10 atomic% of Si was less than half that of Sample 55. In sample 60 containing 30 atomic% of Si, it was confirmed that the non-linearity was lost and the sample became a resistor. From the results shown in Table 4, the ratio of the second subcomponent with respect to 100 mol of the main component is preferably 1 atomic% ≦ second subcomponent <30 atomic%, more preferably 2 atomic% ≦ second subcomponent in terms of Si. It was confirmed that the component ≦ 20 atomic%, more preferably 5 atomic% ≦ the second subcomponent ≦ 20 atomic%.
[0092]
Table 5 summarizes the Co content and the electrical characteristics, but the CV product is small without any problem. However, no varistor voltage was obtained in samples 67 and 74 having a Co content of 0.05 atomic%. In samples 73 and 80 having a Co content of 50 atomic%, an increase in varistor voltage and a decrease in non-linearity were observed. From the results shown in Table 5, the ratio of the fourth subcomponent with respect to 100 mol of the main component is preferably 0.05 atomic% <the fourth subcomponent <50 atomic%, more preferably 0.1 atomic%, in terms of Co. ≦ fourth subcomponent ≦ 30 at%, particularly preferably 1 at% ≦ fourth subcomponent ≦ 20 at%.
[0093]
Table 6 shows the results when B, Al, Ga and In, which are Group IIIb elements, were contained. In Samples 81 and 95 having an Al content of 0.0001 atomic%, the varistor voltage rapidly increased and exceeded 200 V. Also, no varistor voltage was obtained in samples 94 and 108 having an Al content of 1 atomic%. Further, it was confirmed that B, Ga, and In can be used instead of Al, and that a combination of two or more kinds selected from B, Al, Ga, and In can be used. Also, from the results shown in Table 6, the ratio of the fifth subcomponent to 100 mol of the main component is preferably 0.0001 atomic% <fifth subcomponent <1 atomic% in terms of B, Al, Ga and In. More preferably, 0.0005 atomic% ≦ fifth subcomponent ≦ 0.5 atomic%.
[0094]
Table 7 shows the results when Na, K, Rb, and Cs were contained as alkali metals. In samples 109 and 124 having a K content of 0.005 atomic%, the resistance was low and no varistor voltage was obtained. In the case of samples 123 and 138 having a K content of 5 atomic%, the samples were in a molten state, and electrical characteristics could not be measured. Further, it was confirmed that other alkali metals such as Na, Rb and Cs may be used instead of K, or two or more kinds of alkali metals may be added in combination. From the results shown in Table 7, the ratio of the sixth subcomponent with respect to 100 mol of the main component is preferably 0.005 atomic% <sixth subcomponent <5 atomic%, in terms of Na, K, Rb, and Cs. It was confirmed that preferably 0.05 atomic% ≦ sixth subcomponent ≦ 2 atomic%.
[0095]
Table 8 shows the results when Mg, Ca, Sr and Ba were contained as alkaline earth metals. In the samples 139 and 146 having a Ca content of 0.05 atomic%, the nonlinearity was small, and in the samples 145 and 152 having a Ca content of 5 atomic%, the varistor voltage was rapidly increased. In addition, similar results were obtained when Mg, Sr and Ba were used, and it was confirmed that even when these were used in combination, the effect of containing was obtained. From the results shown in Table 8, the ratio of the seventh subcomponent with respect to 100 mol of the main component is preferably 0.05 atomic% <seventh subcomponent <5 atomic%, in terms of Mg, Ca, Sr and Ba. It was confirmed that preferably 0.1 atomic% ≦ seventh subcomponent ≦ 3 atomic%.
[0096]
Example 2
In this example, the characteristics of the voltage non-linear resistor ceramic composition itself according to the present invention were evaluated.
[0097]
Polyvinyl alcohol as a binder was added to powder (material of the voltage non-linear resistor ceramic composition) having the composition shown in Sample 5 of Table 1, and the binder and the voltage non-linear resistor were formed into granules. The porcelain composition material was mixed. Next, the granular voltage non-linear resistor ceramic composition material was press-molded to obtain a disk-shaped preform having an outer diameter of 16 mm and a thickness of 1.2 mm.
[0098]
Next, the obtained preformed body was subjected to binder removal at 350 ° C. for 2 hours, and then fired at 1200 ° C. for 2 hours in the air to obtain a disc-shaped semiconductor having an outer diameter of 14 mm and a thickness of 1 mm. I got a body.
[0099]
Next, an electrode having a diameter of 11.5 mm was formed by baking Ag on both sides of the disc-shaped semiconductor sintered body, and a disc-shaped sample as a sample of the voltage non-linear resistor ceramic composition of the present invention. Got.
[0100]
Using the obtained disk-shaped sample, the varistor voltage, the nonlinear coefficient, the CV product, and the high-temperature load life characteristic were measured in the same manner as in Example 1. As a result, it was confirmed that the same effect as in Example 1 was obtained.
[0101]
【The invention's effect】
As described above, according to the present invention, sintering can be performed sufficiently, and even if the circuit voltage is reduced, the capacitance can be reduced, and the voltage at a high temperature can be reduced. It is possible to provide a voltage non-linear resistor ceramic composition having excellent load life characteristics, and an electronic component such as a multilayer chip varistor using the composition.
[Brief description of the drawings]
FIG. 1 is a sectional view of a multilayer chip varistor according to one embodiment of the present invention.
[Explanation of symbols]
2. Multilayer chip varistor
4,6 ... Internal electrode layer
8. Interlayer voltage non-linear resistor layer
8a ... Outside protective layer
10. Element body
12, 14 ... External terminal electrodes

Claims (10)

A main component containing zinc oxide;
A first subcomponent containing a rare earth element oxide;
A second subcomponent containing an oxide of Si;
A voltage non-linear resistor porcelain composition comprising: a third subcomponent containing at least one oxide of Cr and Mo;
A voltage nonlinear resistor porcelain composition in which the ratio of the third subcomponent to 100 mol of the main component is 0 atomic% <third subcomponent <2 atomic% in terms of Cr and Mo. 2. The voltage non-linear resistor ceramic composition according to claim 1, wherein a ratio of the first subcomponent with respect to 100 mol of the main component is 0.01 at% <first sub component <10 at% in terms of rare earth element. 3. object. 3. The non-linear resistor ceramic composition according to claim 1, wherein a ratio of the second subcomponent with respect to 100 mol of the main component is 1 atomic% ≦ second subcomponent <30 atomic% in terms of Si. 4. . A fourth subcomponent including an oxide of Co;
The voltage non-linearity according to any one of claims 1 to 3, wherein a ratio of the fourth subcomponent with respect to 100 mol of the main component is 0.05 atomic% <fourth subcomponent <50 atomic% in terms of Co. Resistor porcelain composition. A fifth subcomponent containing at least one oxide selected from B, Al, Ga and In,
The ratio of the fifth subcomponent with respect to 100 mol of the main component is 0.0001 atomic% <fifth subcomponent <1 atomic% in terms of B, Al, Ga and In. 3. The voltage nonlinear resistor porcelain composition according to claim 1. Further comprising a sixth subcomponent containing at least one oxide selected from Na, K, Rb and Cs,
The ratio of the sixth subcomponent with respect to 100 mol of the main component is 0.005 atomic% <sixth subcomponent <5 atomic% in terms of Na, K, Rb and Cs. 3. The voltage nonlinear resistor porcelain composition according to claim 1. Further comprising a seventh subcomponent containing at least one oxide selected from Mg, Ca, Sr and Ba;
The ratio of the seventh subcomponent with respect to 100 mol of the main component is 0.05 atomic% <seventh subcomponent <5 atomic% in terms of Mg, Ca, Sr and Ba. 3. The voltage nonlinear resistor porcelain composition according to claim 1. An electronic component having a voltage non-linear resistor layer,
The voltage non-linear resistor layer is composed of a voltage non-linear resistor ceramic composition,
The voltage nonlinear resistor porcelain composition,
A main component containing zinc oxide;
A first subcomponent containing a rare earth element oxide;
A second subcomponent containing an oxide of Si;
A third subcomponent containing at least one oxide of Cr and Mo,
An electronic component in which the ratio of the third subcomponent to 100 mol of the main component is 0 atomic% <third subcomponent <2 atomic% in terms of Cr and Mo. A multilayer chip varistor having a voltage non-linear resistor layer,
The voltage non-linear resistor layer is composed of a voltage non-linear resistor ceramic composition,
The voltage nonlinear resistor porcelain composition,
A main component containing zinc oxide;
A first subcomponent containing a rare earth element oxide;
A second subcomponent containing an oxide of Si;
A third subcomponent containing at least one oxide of Cr and Mo,
A multilayer chip varistor in which the ratio of the third subcomponent with respect to 100 mol of the main component is 0 atomic% <third subcomponent <2 atomic% in terms of Cr and Mo. A multilayer chip varistor having a voltage non-linear resistor layer,
The voltage non-linear resistor layer is composed of a voltage non-linear resistor ceramic composition,
The voltage nonlinear resistor porcelain composition,
A main component containing zinc oxide;
A first subcomponent containing a rare earth element oxide;
A second subcomponent containing an oxide of Si;
A third subcomponent containing at least one oxide of Cr and Mo;
A fourth subcomponent containing an oxide of Co;
A fifth subcomponent containing at least one oxide selected from B, Al, Ga, and In;
A sixth subcomponent containing at least one oxide selected from Na, K, Rb and Cs;
A seventh subcomponent containing at least one oxide selected from Mg, Ca, Sr, and Ba;
The ratio of each component to 100 moles of the main component,
0.01 atomic% in terms of rare earth element <first subcomponent <10 atomic%,
1 atomic% in terms of Si ≦ second subcomponent <30 atomic%,
0 atomic% in terms of Cr and Mo <third subcomponent <2 atomic%,
0.05 atomic% in terms of Co <fourth subcomponent <50 atomic%,
0.0001 atomic% in terms of B, Al, Ga and In <fifth subcomponent <1 atomic%,
0.005 atomic% in terms of Na, K, Rb and Cs <sixth subcomponent <5 atomic%,
0.05 atomic% in terms of Mg, Ca, Sr and Ba <seventh subcomponent <5 atomic%,
Is a multilayer chip varistor.

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