KR20210007123A - ZnO-BASED VARISTOR COMPOSITION AND MANUFACTURING METHOD AND VARISTOR THEREOF - Google Patents

Abstract

According to the present invention, a ZnO-based varistor composition does not comprise Bi_2O_3, Pr_6O_11, and V_2O_5 but comprises ZnO, a liquid sintering aid simultaneously adding TeO_2 and Bi_2WO_6, and an Mn oxide. The varistor composition is formed in a disk shape and forms a sintered body by sintering in a temperature range of 800-900°C, and a disk-type varistor can be manufactured by attaching external electrodes to both sides of the sintered body. The present invention can lower a sintering temperature, increase nonlinearity, and obtain a composition having excellent material properties required in a varistor to greatly improve the characteristics of a varistor.

Description

ZnO-based varistor composition, its manufacturing method, and varistor {ZnO-BASED VARISTOR COMPOSITION AND MANUFACTURING METHOD AND VARISTOR THEREOF}

The present invention relates to a ZnO-based varistor composition, and more particularly, to a ZnO-based varistor composition containing zinc oxide (ZnO) as a main component, a method for producing the same, and a varistor.

The ZnO-based varistor is formed of a Bi-ZnO or Pr-ZnO-based composition of the varistor material composition system. Compared to SnO ₂ varistors, SiC varistors and SrTiO ₃ varistors, ZnO varistors have excellent voltage nonlinearity and excellent ability to protect electronic devices from static electricity (ESD) and various surges. It is widely used as a material.

Bi-ZnO-based varistors contain components such as Bi ₂ O ₃ , Sb ₂ O ₃ , Mn, Co, Ni, Cr, glass frit, Al, and K. However, Bi ₂ O ₃ components have four kinds of homogeneity or higher, and when the breakdown voltage is lowered to 10 V or less, ESD (Electro-Static Discharge) resistance is weak, so Bi-ZnO varistors including them also have poor ESD characteristics. .

However, Bi-ZnO-based varistors have attempted to increase the ESD resistance characteristics by adding V ₂ O ₅ as a sintering aid to the above composition. The V ₂ O ₅ component itself melts at 670°C, but when added to ZnO in a small amount of 20 mol% or less, it forms Zn ₃ V ₂ O ₈ or By forming intermediate products such as Zn ₄ V ₂ O ₉ at a higher temperature, sintering densification is possible at 900°C where these intermediate products are melted, increasing the sintering temperature to 900°C, high leakage current and low nonlinearity Has.

Pr-ZnO-based varistors have approximately good voltage nonlinearity, but have a drawback in that the leakage current is larger and surge tolerance is slightly lower than that of Bi-ZnO-based varistors, and Pr ₆ O ₁₁ (or Pr ₂ O ₃ )-Based components require high-temperature sintering (around 1200°C), and when manufacturing a stacked chip varistor, a large amount of expensive components (Pd, Pt, etc.) are used as internal electrodes, resulting in a high manufacturing cost.

An object of the present invention is to induce a process liquid phase that can be produced at a temperature lower than each melting point by simultaneously adding zinc oxide (ZnO) as a main component and TeO ₂ and Bi ₂ WO ₆ , and including Mn oxide as a _secondary component. It is to provide a ZnO-based varistor composition, a method of manufacturing the same, and a varistor that can secure the physical properties of a varistor by increasing its properties.

According to the features of the present invention for achieving the above object, the ZnO-based varistor composition of the present invention does not contain Bi ₂ O ₃ , Pr ₆ O ₁₁ and V ₂ O ₅ , and ZnO, TeO ₂ and Bi ₂ It includes a liquid phase sintering aid and Mn oxide for simultaneously adding WO ₆ .

The ZnO-based varistor composition further includes at least one or more from the group consisting of Co ₃ O ₄ , CaCO ₃ , Sb ₂ O ₃ , SiO ₂ and Cr ₂ O ₃ as an accessory component.

The ZnO-based varistor composition includes 99.6 to 86.7 mol% of ZnO, 0.3 to 2 mol% of a liquid sintering aid for simultaneously adding TeO ₂ and Bi ₂ WO ₆ and 0.1 to 1 mol% of Mn oxide based on the total weight of the composition.

The molar ratio of TeO ₂ and Bi ₂ WO ₆ (TeO ₂ /Bi ₂ WO ₆ ) is 0.5 to 2.0.

ZnO-based varistor composition is a subcomponent based on the total weight of the composition.Co ₃ O ₄ 0.1 ~ 1 mol%, CaCO ₃ 0.2 ~ 3 mol%, Sb ₂ O ₃ 0.1 ~ 3 mol%, SiO ₂ 0.2 ~ 3 mol% and Cr ₂ O ₃ 0.1 ~ 0.3 It further includes at least one or more in the group consisting of mol%.

The Mn oxide is selected from the group consisting of MnO, MnO ₂ , Mn ₂ O ₃ and Mn ₃ O ₄ .

The ZnO-based varistor composition is molded into a disk shape and sintered in a temperature range of 800 to 900°C to form a disk-type sintered body, and external electrodes are attached to both surfaces of the disk-type sintered body to manufacture a disk-type varistor.

The ZnO-based varistor composition is tape-cast to form a plurality of sheets, and after coating and laminating an electrode material for forming internal electrodes on the surfaces of each of the plurality of sheets, the laminate is sintered at a temperature of 800 to 900°C. And forming external electrodes at both ends of the stack to be connected to the internal electrodes to manufacture a stacked chip varistor.

It includes a sintered body having a component of a ZnO-based varistor composition, and an external electrode formed on both surfaces of the sintered body to function as input/output of electric signals.

The sintered body of the ZnO-based varistor composition and the sintered body are buried so as to be spaced apart from each other up and down, and are formed at both ends of the sintered body and a plurality of internal electrodes that function to input and output an electric signal and external electrodes connected to the internal electrodes.

The internal electrode is one of 100% Ag, 100% Al, and an alloy of Ag and Al.

The present invention includes a liquid sintering aid and Mn oxide simultaneously adding ZnO, TeO ₂ and Bi ₂ WO ₆ without including Bi ₂ O ₃ , Pr ₆ O ₁₁ (Pr ₂ O ₃ ) and V ₂ O ₅ This lowers the sintering temperature, increases the nonlinearity, and secures the properties of the varistor.

Therefore, the present invention can secure the overall excellent physical properties (ESD, prevention of increase in leakage current) required by the varistor, while sintering at a temperature of 800 to 900°C, so that low-cost internal electrodes such as 100% Ag or Al or an alloy thereof can be used. It can be used and has the effect of significantly lowering the production cost.

In addition, the present invention further includes oxides such as Co, Ca, Sb, Si, Cr, etc. as an auxiliary component, so that a composition having excellent physical properties required for a varistor can be obtained, thereby greatly improving the properties of the varistor.

1 is a schematic diagram showing an example of a disk type varistor according to an embodiment of the present invention.
2 is a schematic diagram showing an example of a chip type varistor according to an embodiment of the present invention.
3 is a graph showing a current (I)-voltage (V) curve of the ZnO-based varistors prepared in Examples 1 to 7 of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The ZnO-based varistor composition of the present invention does not contain Bi ₂ O ₃ , Pr ₆ O ₁₁ (Pr ₂ O ₃ ) and V ₂ O ₅ , and a liquid sintering aid which simultaneously adds ZnO, TeO ₂ and Bi ₂ WO ₆ and Contains Mn oxide.

Bi ₂ O ₃ is not included because it negatively affects the ESD characteristics of the varistor by deteriorating the ZnO-based electro-static discharge (ESD) resistance. Pr ₆ O ₁₁ (Pr ₂ O ₃ ) is not included as it requires high-temperature sintering and causes an increase in the manufacturing cost of varistors. V ₂ O ₅ increases leakage current of varistors, has low nonlinearity, and is a single addition type capable of sintering above 900℃, so it is not included.

More specifically, Bi ₂ O ₃ has the advantages of high nonlinearity, high surge tolerance, and low sintering temperature, but has a disadvantage in that it forms a complex microstructure due to a large number of additives and lowers ESD resistance as a product with low capacitance. Pr ₆ O ₁₁ (Pr ₂ O ₃ ) has the advantage of forming a simpler microstructure and high ESD resistance due to fewer types of additives, but has disadvantages of having high sintering temperature, relatively low nonlinearity and surge tolerance.

Therefore, the ZnO-based varistor composition according to an embodiment of the present invention does not contain Bi ₂ O ₃ , Pr ₆ O ₁₁ (Pr ₂ O ₃ ) and V ₂ O ₅ , but instead TeO ₂ and Bi ₂ WO ₆ are simultaneously added. Thus, a eutectic liquid that can be generated at a temperature lower than each melting point is induced, and a varistor composition having excellent physical properties including Mn oxide is obtained.

Inducing a process liquid phase that can be generated at a temperature lower than each melting point can induce densification of ZnO and uniformity of the microstructure, thereby improving the properties of varistors.

ZnO is a non-stoichiometric n-type semiconductor with linear IV behavior. The higher the nonlinearity, the better the varistor characteristics. Therefore, Mn oxide is included to make non-linearity, and it acts as a liquid sintering aid by adding TeO ₂ and Bi ₂ WO ₆ at the same time.

The liquid sintering aid is simultaneously added with TeO ₂ and Bi ₂ WO ₆ to enable sintering at a temperature of 800 to 900°C. If sintering is possible at a temperature of 800 to 900°C, an ultra-high pressure disk type varistor or low-cost internal electrodes such as 100% Ag or Al or an alloy thereof can be used and the production cost can be greatly reduced.

In addition, oxides such as Co, Ca, Sb, Si, and Cr are further included as auxiliary components in order to obtain a composition having excellent overall physical properties required for the varistor. Specifically, it further includes at least one or more of Co ₃ O ₄ , CaCO ₃ , Sb ₂ O ₃ , SiO ₂ and Cr ₂ O ₃ as an auxiliary component. For example, each or part of Co ₃ O ₄ , CaCO ₃ , Sb ₂ O ₃ , SiO ₂ and Cr ₂ O ₃ are included as subcomponents.

The varistor composition basically contains 99.6 to 86.7 mol% of ZnO, 0.3 to 2 mol% of a liquid sintering aid for simultaneously adding TeO ₂ and Bi ₂ WO ₆ and 0.1 to 1 mol% of Mn oxide based on the total weight of the composition, and subcomponents therein At least in the group consisting of Co ₃ O ₄ 0.1~1 mol%, CaCO ₃ 0.2~3 mol%, Sb ₂ O ₃ 0.1~3 mol% SiO ₂ 0.2~3 mol% and Cr ₂ O ₃ 0.1~0.3 mol% It may further include one or more.

TeO ₂ and Bi ₂ WO ₆ are added at the same time, but the molar ratio (TeO ₂ /Bi ₂ WO ₆ ) is 0.5 to 2.0. Specifically, TeO ₂ and Bi ₂ WO ₆ are added at the same time, but the molar ratio (TeO ₂ /Bi ₂ WO ₆ ) is 0.5 to 2.0, and the total amount of TeO ₂ and Bi ₂ WO ₆ is 0.3 to 2 mol%.

TeO ₂ and Bi ₂ WO ₆ are added at the same time, but the molar ratio (TeO ₂ /Bi ₂ WO ₆ ) is 0.5 to 2.0, and the total amount of TeO ₂ and Bi ₂ WO ₆ is 0.3 to 2 mol%. This is to give the role of a liquid sintering aid by inducing the process liquid during (or sintering). This plays a similar role to the well-known Bi ₂ O ₃ , Pr ₆ O ₁₁ and V ₂ O ₅ in ZnO-based varistors, and when included in the above content range, sintering is possible at 800 to 900°C, yet required for varistors. A composition having excellent overall physical properties can be obtained.

Mn oxide is included to obtain high nonlinearity. The higher the nonlinearity, the better the varistor characteristics. The Mn oxide may be selected from the group consisting of MnO, MnO ₂ , Mn ₂ O ₃ and Mn ₃ O ₄ . Preferably, the Mn oxide may be Mn ₃ O ₄ .

When the Mn oxide is included in the range of 0.1 to 1 mol%, a composition having excellent overall physical properties required for the varistor can be obtained. If Mn oxide is contained in less than 0.1 mol%, it has no effect, and if it is contained in more than 1 mol%, ZnO suppresses densification and grain growth, and sintering of the composition is not well performed, resulting in lower sintering density and high varistor voltage. do.

The nonlinearity of the ZnO-based varistor is expressed by the grain boundary phenomenon, and excellent varistor characteristics are obtained only when uniform grain growth and uniform microstructure are formed during sintering. Therefore, by including Mn oxide in the range of 0.1 to 1 mol%, uniform grain growth and uniform microstructure are formed during sintering.

In the case of Co ₃ O _{4 in} the case of Co ₃ O ₄ , when it is included in the range of 0.1 to 1 mol%, a composition having excellent physical properties required for the varistor can be obtained, and when it exceeds 1 mol%, the composition is sintered by suppressing the densification and grain growth of ZnO. Due to this slowdown, the sintering density may decrease, and the properties of the varistor may also decrease.

In the case of CaCO ₃ , if it is included in the range of 0.2 to 3 mol%, it promotes sintering to increase the ZnO particles, lower the varistor voltage, and increase nonlinearity, and when added in excess of 3 mol%, initial sintering It suppresses densification and results in an increase in leakage current.

In the case of Sb ₂ O _{3 as} a subcomponent, when it is included in the range of 0.1 to 3 mol%, a composition with somewhat excellent overall physical properties required for the varistor can be obtained, and ZnO grain growth by forming a spinel phase such as Zn ₇ Sb ₂ O ₁₂ By effectively suppressing the control of the varistor properties and the varistor voltage can be obtained more stable. In the case of Sb ₂ O ₃ , if it is added in excess of 3 mol%, the sintering density decreases and the sintering temperature is increased, resulting in a large increase in varistor voltage.

In the case of SiO ₂ , when the sub-component is included in the range of 0.2 to 3 mol%, the nonlinearity is improved to a certain degree and the ZnO grain growth is somewhat suppressed. In the case of SiO ₂ , if it contains more than 3 mol%, the nonlinearity continues to improve, but the sintering density decreases and a higher varistor voltage is formed.

In the case of Cr ₂ O _{3 in} the case of Cr ₂ O ₃ , when it is included in the range of 0.1 to 0.3 mol%, a composition having excellent overall physical properties required for the varistor can be obtained, and when it exceeds 0.3 mol%, the leakage current increases and the nonlinearity is low. The result is that the sintering density is lowered.

It can be manufactured as an ultra-high pressure disk type varistor or a stacked chip type varistor using the above-described ZnO-based varistor composition.

On the other hand, the manufacturing method of a disc-type varistor using a ZnO-based varistor composition includes the steps of mixing and pulverizing a ZnO-based varistor composition containing a liquid sintering aid, Mn oxide and subcomponents in a ZnO powder into a ball mill, and assembling by dehydrating and drying treatment. It includes preparing powder and using it as a starting material, putting a predetermined amount of starting material powder into a molding mold and preforming to form a disk type, and sintering the disk type to produce a sintered body.

Sintering is carried out in the range of 800 to 900°C.

The method of manufacturing a ZnO chip type varistor includes the steps of preparing a slurry by putting a ZnO-based varistor composition into a ball mill and mixing it into a slurry, and preparing a ceramic sheet having a thickness of several tens of µm by tape casting, and applying an Ag or Al electrode paste on the sheet. It includes a step of printing by coating or screen printing, laminating into multiple layers, cutting into chips, and sintering.

The method of manufacturing the disk-type or chip-type varistor described above is a liquid phase in which the molar ratio of ZnO 99.6 to 86.7 mol%, TeO ₂ and Bi ₂ WO ₆ (TeO ₂ /Bi ₂ WO ₆ ) to the total weight of the composition is 0.5 to 2.0. Sintering aid 0.3~2 mol%, Mn oxide 0.1~1 mol% as the basic composition, and as subcomponents here, Co ₃ O ₄ 0.1~1 mol%, CaCO ₃ 0.2~3 mol%, Sb ₂ O ₃ 0.1~3 mol%, SiO ₂ 0.2 ~ 3 mol% and Cr ₂ O _{3 In} the group consisting of 0.1 ~ 0.3 mol%, except for the use of a ZnO-based varistor composition further containing at least one or more, it can be carried out by employing a method known in the art. have.

1 is a schematic diagram showing an example of a disk type varistor according to an embodiment of the present invention.

As shown in Fig. 1, the ZnO-based varistor composition powder is molded and sintered into a single disk 12, and then a metal electrode material is coated on both surfaces of the disk 12 or printed by screen printing to provide external electrodes. By forming (13), it can be manufactured into a general disk type varistor (10). In the disk type varistor 10 having a shape that cannot be surface mounted, a lead wire 14 may be attached to the external electrode 13 for inputting an electric signal.

As shown in FIG. 2, the ZnO-based varistor composition powder is formed into a plurality of sheets, and then a plurality of these sheets are stacked to form a stacked body 32, but dummy sheets to be disposed on the uppermost layer and the lowermost layer respectively (electrode materials are On the sheets to be laminated therein, except for sheets that are not coated), an electrode material for forming the internal electrodes 33 is applied on the surface or printed by screen printing, and the sheets and dummy sheets therein are sequentially. The laminated varistor 30 may be manufactured by laminating and sintering. As the electrode material, an electrode material such as Ag, Al, or Ag/Al alloy may be used. In addition, external electrodes 35 may be formed at both ends of the varistor for input/output of electrical signals, and may be electrically connected to the internal electrodes 33, respectively. The stacked varistor 30 may be based on a known MLCC (Multi-Layer Ceramic Capacitor) manufacturing method.

Hereinafter, the present invention will be described through examples.

Table 1 shows the ZnO-based varistor composition.

Composition table POWER (mol%) ZnO TeO ₂ Bi ₂ WO ₆ Mn ₃ O ₄ Co ₃ O ₄ CaCO ₃ Sb ₂ O ₃ SiO ₂ Example 1 98.5 0.5 0.5 0.5 Example 2 98.5 0.5 0.5 0.5 Example 3 97.5 0.5 0.5 0.5 0.5 0.5 Example 4 98.0 0.5 0.5 0.5 0.5 Example 5 97.5 0.5 0.5 0.5 0.5 0.5 Example 6 97.0 0.5 0.5 0.5 0.5 0.5 0.5 Example 7 96.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

The ZnO-based varistor composition of Table 1 was put into a ball mill containing 3 times of distilled water and 5 mmφ partially stabilized zirconia (YSZ), mixed, and pulverized. Then, for dehydration and drying treatment, granulated powder was prepared and used as a starting material. A predetermined amount of the starting material powder was put into a 10mmφ molding mold and uniaxially formed into a disk type by temporary molding at a pressure of 50 MPa at 800°C (Example 1), 900°C (Examples 2 to 3), and 950°C (Example 4). It was sintered in air for 1 hour at ~7).

The sintered body obtained by the above method is polished on both sides to make a thickness of about 1 mm, and then Ag paste for ohmic contact is applied to both ends of the ceramic sintered body, and then baked at 550℃ for 10 minutes to form external electrodes. A specimen for measurement was prepared.

The current (I)-voltage (V) characteristics of the ZnO-based varistors fabricated in Examples 1 to 7 above were measured in a log stair pulse waveform at room temperature using a DC current voltage power supply and a high voltage source measure (Keithley 237). It was measured by applying.

The varistor voltage (Vn), which is a current-voltage characteristic parameter, is the voltage when 1mA/㎠ current flows, measured in [V/mm], and the leakage current (I _L ) is the current measured at 80% of Vn [㎂/ Cm2], and the nonlinear coefficient (α) was calculated using the following equation. The measured values are shown in Table 2 below.

[Equation 1]

Here, E1 and E2 are electric fields at J ₁ (=1mA/cm2) and J ₂ (=10mA/cm2), respectively.

Table 2 shows the measured values of the relative density, voltage, nonlinear coefficient, and leakage current of the ZnO-based varistors manufactured in Examples 1 to 7 of Table 1.

division Sintering temperature
(℃) Relative density
(g/cm3) Vn
(V/mm) Nonlinear coefficient
(α) Leakage current
(㎂/㎠) Example 1 800 97.3 935 53 17 Example 2 900 98.4 767 69 0.5 Example 3 900 97.4 604 35 5 Example 4 950 98.0 445 39 0.7 Example 5 950 97.5 731 65 9 Example 6 950 98.2 420 37 0.1 Example 7 950 96.6 934 46 5

According to Table 2, it can be seen that the varistor prepared from the ZnO-based varistor composition of the present invention has a high density, excellent nonlinearity in the composition range, a low leakage current, and excellent varistor characteristics.

In the case of Examples 1 to 3 sintered at a temperature of 800 to 900°C, there was no shortage in density, nonlinearity, and leakage current even compared to Examples 4 to 7 sintered at 950°C. This means that even when the ZnO-based varistor composition of the embodiment is sintered at 800 to 900°C, excellent varistor properties can be secured.

3 is a graph showing a current (I)-voltage (V) curve of the ZnO-based varistors manufactured in Examples 1 to 7 of the present invention.

As shown in FIG. 3, it is confirmed that the varistors of Examples 1 to 7 exhibit high nonlinearity. High nonlinearity causes a large current to flow in response to a small increase in voltage. The degree of nonlinearity is expressed as I = CV ^α and is determined by the flatness (nonlinear coefficient α) of the nonlinear IV curve. The larger the α value, the better the varistor characteristics.

Varistors are semiconducting variable resistance devices with nonlinear current-voltage characteristics, and are electronic ceramic components that repeatedly detect and limit instantaneous voltage fluctuations within 1ns without destroying the product. Therefore, high nonlinearity, high surge tolerance, and low sintering temperature are required.

ZnO based varistor composition of the present invention to increase the Bi ₂ O _3, leakage currents have a negative effect on the ESD properties of the non-linearity is low and is required to sinter the possible sole cheomgahyeong V ₂ O _5, the high temperature sintering at above 900 ℃ manufacturing costs It does not contain the Pr ₆ O ₁₁ (Pr ₂ O ₃ ) component causing an increase, and includes TeO ₂ and Bi ₂ WO ₆ as a new liquid sintering aid by replacing it. In addition, it is possible to secure overall excellent physical properties required by varistors, including Mn oxide and subcomponents.

In addition, since it is sintered at a temperature of 800 to 900°C, it is possible to use a disk type varistor for ultra-high pressure or a low-cost internal electrode such as 100% Ag or Al or an alloy thereof, and the production cost can be greatly reduced.

Varistors prepared using the above-described ZnO-based varistor composition can be used in various automotive modules in the case of a disk type, and can be applied to various high-tech devices in the case of a chip type.

The present invention has been disclosed in the drawings and the specification, the best embodiments. Here, specific terms have been used, but these are only used for the purpose of describing the present invention, and are not used to limit the meaning or the scope of the present invention described in the claims. Therefore, the present invention will be understood by those of ordinary skill in the art that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical scope of the present invention should be determined by the technical idea of the appended claims.

10: disc type varistor 12: disc
13: external electrode 14: lead wire
30: chip varistor 32: laminate
33: internal electrode 35: external electrode

Claims (11)

Does not contain Bi ₂ O ₃ , Pr ₆ O ₁₁ and V ₂ O ₅ ,
ZnO;
Liquid sintering aid for simultaneously adding TeO ₂ and Bi ₂ WO ₆ ; And
Mn oxide; ZnO-based varistor composition comprising a. The method according to claim 1,
ZnO-based varistor composition further comprising at least one or more from the group consisting of Co ₃ O ₄ , CaCO ₃ , Sb ₂ O ₃ , SiO ₂ and Cr ₂ O ₃ as an accessory component. The method according to claim 1,
To the total weight of the composition
ZnO-based varistor composition comprising 99.6 to 86.7 mol% of ZnO, 0.3 to 2 mol% of a liquid sintering aid for simultaneously adding TeO ₂ and Bi ₂ WO ₆ and 0.1 to 1 mol% of Mn oxide. The method according to claim 2
The mole ratio of TeO ₂ and Bi ₂ WO ₆ (TeO ₂ /Bi ₂ WO ₆ ) is 0.5 to 2.0 ZnO-based varistor composition. The method according to claim 2,
Based on the total weight of the composition
At least one from the group consisting of Co ₃ O ₄ 0.1 ~ 1 mol%, CaCO ₃ 0.2 ~ 3 mol%, Sb ₂ O ₃ 0.1 ~ 3 mol%, SiO ₂ 0.2 ~ 3 mol%, and Cr ₂ O ₃ 0.1 ~ 0.3 mol% ZnO-based varistor composition further comprising. The method according to claim 1,
The Mn oxide is
MnO, MnO ₂ , Mn ₂ O ₃ and Mn ₃ O ₄ ZnO-based varistor composition selected from the group consisting of. The ZnO-based varistor composition of any one of claims 1 to 6 is molded into a disk shape, and sintered at a temperature of 800 to 900°C to form a disk-type sintered body, and external electrodes are attached to both sides of the disk-type sintered body. ZnO-based varistor manufacturing method for manufacturing type varistor. The ZnO-based varistor composition of any one of claims 1 to 6 is tape-cast to form a plurality of sheets, and after coating and laminating an electrode material forming an internal electrode on each surface of the plurality of sheets, 800 to 900°C A method of manufacturing a ZnO-based varistor for manufacturing a multilayer chip varistor by sintering at a temperature range of to form a laminate, and forming external electrodes at both ends of the laminate to be connected to the internal electrodes. The sintered body of the ZnO-based varistor composition according to any one of claims 1 to 6; And
ZnO-based varistor comprising; external electrodes formed on both sides of the sintered body to function input/output of electric signals. The sintered body of the ZnO-based varistor composition according to any one of claims 1 to 6;
A plurality of internal electrodes buried in the sintered body so as to be spaced apart from each other up and down so as to input and output electrical signals; And
External electrodes formed on both ends of the sintered body and connected to the internal electrodes;
ZnO-based varistor containing a. The method of claim 10,
The internal electrode is 100% Ag, 100% Al, ZnO-based varistor, one of an alloy of Ag and Al.

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