JPS60152004A - Method of producing zinc oxide nonlinear resistor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to a method for manufacturing a zinc oxide nonlinear resistor.

[Prior art and problems]

Generally, zinc oxide nonlinear resistor (hereinafter referred to as ZnO element)
For example, a device with a formulation containing at2o3 as the main additive and several other metal oxides is used. This element undergoes a heat treatment process at 400'C to 900°C to improve fire resistance and insulate the outer periphery of the element, but this heat treatment significantly reduces the voltage-current nonlinear characteristics of the element. There are drawbacks to this. The reason for this property deterioration is that the B12O3 crystal structure is changed by heat treatment. In addition, the above element has a certain current range (usually 1
The non-linear characteristic at 00 μA to IA) has a non-linear index (b) greater than or equal to the sum, but there is a drawback that the characteristic deteriorates extremely below or above this value. Furthermore, B12O3, which is the main additive, has a Clark number of 2×10 2 for the Bi element, which is a poor resource.

[Purpose of the invention]

It is an object of the present invention to provide a method for manufacturing a zinc oxide nonlinear resistor that eliminates the above-mentioned drawbacks, prevents deterioration of nonlinear characteristics due to heat treatment, and reduces leakage current even when the current is low. purpose.

[Summary of the invention]

In order to achieve the above object, this invention
, 5b2o3 was heat-treated at 800 to 1100°C to form ZnO, MnO2, 15b205, Cr2O5.
, Co2O3 and ZnO, MnO2, 5b203, C
r2O5, Co2O3 and Az2o5.

C020 and zinc borosilicate glass, Co2O3, Al2
It has a structure in which O5 and zinc borosilicate glass powder are mixed together, pressure molded, and the molded product is heat-treated.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

First, predetermined amounts of pbo and 5b2o5 were weighed out at a molar ratio of 2:1, mixed well in a centrifugal ball mill, and then calcined at 1000° C. for 4 hours in an alumina crucible. The calcined powder thus calcined is pulverized in an f++I ball mill to obtain a reaction product. After that, 2no: 9
8.0 mail, MnO2: 0.5 mail, 5
b2o3: 0.5 mail, Cr2O3: 0.5
mail, CO2O3: A predetermined amount of 0.5 mo1% is weighed, two of the above reactants are added thereto in a weight ratio, the powders are mixed well, and the powder is press-molded into a disk shape. after that,
After firing the molded body in air at 1100°C for 6 hours, both end surfaces of the molded body ? Polished, coated with Ag electrode, heated at 590°C for 1
Perform heat treatment for an hour.

FIG. 1 is a characteristic diagram showing the voltage-current characteristics of the ZnO device manufactured according to the above example and the voltage-current characteristics of the ZnO device without adding CO2O3. In the figure, curve A is that of the device according to this example, curve I ! J! B is the latter element. As is clear from FIG. 1, the non-linear IllIlIrf property in the current region does not deteriorate significantly in this embodiment. However, in the same way as described as the prior art to those of the latter element, non-direct &! Characteristics become extremely poor.

Figure 2 shows the amount of Co2O3 added when 2 is added to 1.
1 is a characteristic diagram of a curve A showing a 1α1.0 value (a nonlinear index when the current is between 0.1 kite and 1.0 mA) and a curve B showing a change in v1 mA/−.

As is clear from the above FIGS. 1 and 2, the device according to this example has superior nonlinear characteristics as compared to the device to which Co2O3 is not added.

The best heat treatment temperature for the sintered body is 500°C to 850°C; below that, the life characteristics will not improve, and above 850°C, the non-glandular properties will deteriorate. Furthermore, the heat treatment time varies depending on the size of the element, but is preferably 1 hour or more, and the temperature rising and cooling rate is 200°C/F so that the element does not become distorted due to rapid heating, cooling, etc. j or less is preferable. Note that, if the firing temperature is preferably 1,000 to 1,300°C, a dense sintered body will not be obtained, and if it is higher than 1,300°C, pbo will volatilize and non-linearity will be a problem. The firing time is preferably 1 to 20 hours, but a uniform sintered body cannot be obtained within 1 hour. And above the gap, the volatilization of pbo and 5b2o3 near the surface cannot be ignored.

From the above results, the range of each additive component in the ZnO element manufacturing method is PbO, 5bzO3 reactant, 0.2 to 20 w
t section, MnO2f 0.1~5 tnolqb, 5b
203 f 0.1~5rno1%, Cr2O3f 0
．． 1~5 mo 1%, Co20s'it O-1~
It is preferable to set it to 5 molcS; if it is less than this range, no effect will appear, and if it is more than this, nonlinearity will be lowered.

Although a centrifugal ball mill, an alumina crucible, etc. were used in the above embodiments, other types of these may be used.

Ic, to describe the second embodiment of this invention, pbo
, Reactant for 5b205? I: The means for obtaining is the same as in the first embodiment. After obtaining the reaction product of Pb0, 8b203, ZnO: 97.997 mail, MnO
2: 0.5 moH6,5b205: 0.5 m
ail, Cr2O3: 0.5 mall, Co2
O3: (L5 mail, klzo5: 3/100
A predetermined amount of 0 mol f is weighed, two parts of the above-mentioned reactant is added thereto in a weight ratio, these powders are mixed well, and the powder is press-molded into a disk shape. Thereafter, processing is performed in the same manner as in the previous embodiment.

FIG. 3 is a characteristic diagram showing the voltage-current characteristics of the ZnO element manufactured according to the second example and the voltage-current characteristics of the ZnO element added only with Co20B. In the figure, curve A is that of the element according to the present example. , curve B is for the latter element.

Figure 4 t-1 [2 Actual Ifi Examples Nioee C1klz05
Curve A showing the nonlinear index α value of devices manufactured by fixing k and V to 1000 mol and changing the amount of CO2O3 added.
and α of the device manufactured by changing only the amount of Co2O3 added.
FIG. 3 is a characteristic diagram of a curve B showing the α value and a curve C showing the α value of elements manufactured by changing only the amount of ht2o5 added.

As is clear from FIGS. 3 and 4 above, the device according to this example has excellent non-@Ivi1 characteristics up to a large current range, compared to devices in which Co2O3 and At203 are individually added.

Note that the heat treatment temperature, time, etc. of the element in the second example are the same as in the first example. In addition, each additive component contains 0.2 to 20 wt% of pbo and 5b2o3 reactants.
, MnO2 Q, 1~5 mo 1%, 5b203
f Q,l ~5m01%, Cr2O5k 0.1~5
mail, Co20skO01~5mol1%, At2
05k 0.2/1000~20/1000 mo
It is preferable to set it to 11; if it is less than this range, no effect will be seen, and if it is more than this range, nonlinearity will decrease.

Next, to describe a third embodiment of the present invention, pbo
The means for obtaining the reactant from +5b205 is the same as in the first embodiment. After obtaining the reactants of PbO and 5bzO5, ZnO: 98. Omoil, MnO2: 0.5
moil, 5b205: 0.5 moil, Cr
2O5: 0.5 mail, CO2O3: 0.5
mo 1%, n, zinc silicate glass X: 0.2 w
A sufficient amount of t9Ji is weighed, two of the above reactants are added thereto in a weight ratio, the powders are mixed well, and the powder is press-molded into a disk shape. Thereafter, processing is performed in the same manner as in the previous embodiment.

Figure 5 shows the voltage-current characteristics of the ZnO element manufactured according to the third example and the ZnO element to which only zinc silicate glass was added.
A characteristic diagram showing the voltage-current characteristics of an O element.

In the figure, curve A is for the element according to this example, and curve B is for the latter element.

FIG. 6 shows curve A showing the nonlinear index α value of the device manufactured by fixing the amount of CO2O3 and changing the amount of added zinc silicate glass in the third embodiment, and the curve A showing the nonlinear index α value of the zinc silicate glass. Only the amount added? It is a characteristic diagram of a curve B showing the α value of the element manufactured by changing the amount of 0203 and a curve C showing the α value of the element manufactured by changing only the amount of added 0203.

Figure 7 is a characteristic diagram showing the increase in leakage current when a DC voltage of 85°C of VzrrA is applied in a constant temperature oven at 130°C.
Straight line A shows the fF properties of the element according to the third embodiment and the addition of CO2O3&''j, and straight line B shows the properties when only zinc borosilicate glass is added.

As is clear from FIGS. 5 to 7 above, the device according to this example has superior nonlinear characteristics up to a large current range, compared to devices in which each of CO2O3 and zinc silicate glass is added individually.

Note that the heat treatment temperature, time, etc. of the element in the third example are the same as in the first example. In addition, the range of each additive component is PbO, 5b203 reactant from 0.2 to 20wt96,
MnO2k 0.1~5 mall, 5b2o3 wo0
．． 1-5 mol, Cr205k 0.1-5 mo
11. It is preferable that Co2O3 is 0.1 to 5 mo1% and lI zinc silicate glass is 0.01 to 5 wt. If it is less than this range, no effect will be obtained, and if it is more than this, nonlinearity will decrease. .

Next, to describe a fourth embodiment of the present invention, PbO
, 5b205 is the same as in the first embodiment. After obtaining the reactants of pbo, 5b2o3, ZnO: 97.997 mol (16, MnO2
: 0.5mole, 5bzo5: 0. S mol
Cr2O5: 0. S mol staff, Co2O3
: 0.5 molli, Al2O5: 3/10
00 mol of zinc silicate glass: Weigh the necessary amount of 0.2 wt, add 2 of the above reactants in a weight ratio, mix these powders well, and pressurize into a disk shape. Acid form. Thereafter, processing is performed in the same manner as in the previous embodiment.

FIG. 8 shows the voltage-current characteristics of the ZnO element manufactured according to the fourth example, and the characteristics of the ZnO element manufactured according to the fourth example.
Zinc silicate glass, ZnO from which Co2O3 has been removed
This is a characteristic diagram showing the voltage-current characteristics of the device. In the figure, curve A is the device according to this example, curve B is the device from which At2o3 is removed, curve C is the device from which zinc borosilicate glass is removed, and the curved line is for the device from which CO2O3 was removed. This is from the removed element.

FIG. 9 shows a curve A showing the nonlinear index α value of a device manufactured in Example 4, using a composition other than zinc silicate glass and varying the amount of zinc silicate glass added. , Example p Curve B showing the α value of elements manufactured by changing the amount of zinc silicate glass added with a formulation in which Al2O3 was removed, and a formulation in which the zinc glass was also removed, C
Curve C showing the α value of elements manufactured with different amounts of O2O3 added, and curve C showing the α values of elements manufactured with the same formulation with Co2O3 removed but with different amounts of zinc glass added. be.

Figure 1θ shows the increase in leakage current ΔI/I when a DC voltage of 85 VlmA is applied in a constant temperature bath at 130°C.

In this characteristic diagram, straight line A represents the device of this example, and straight line B represents I? E This is the element after removing the zinc silicate glass. Note that ΔI/1. of the element with At2o5 and CO2O3k removed. was the same as that of the device of this example.

As is clear from Fig. 8 to Fig. 1O above, the element of this example was compared with an element doped with At205, CO2O3, Az2O, and zinc silicate glass, and an element doped with Co2O3 and zinc silicate glass. It has excellent life characteristics and Co2O3, l'! It has superior non-linear characteristics at IOA or higher compared to elements to which zinc silicate glass is added.

Note that the heat treatment temperature, time, etc. of the element in the fourth example are the same as in the first example. In addition, the range line pbo of each additive component, 5b2o3 reactant is 0.2 to 20wt1
, MnO2f 0.1-5 mo 1%, 5b2o3 0.1-5 molc A, C: r205 0.1-5
mo 11, CO2O3 o, i~5mo1%,
Az,, o3 from 0.2/1000 to 20/1000 m
It is preferable to set the content to 0.01 to 5 wt% for curved lead silicate glass, and if it is less than this range, no effect will be obtained.
If it is too large, nonlinearity will decrease.

〔Effect of the invention〕

As described above, according to the present invention, the crystal structure does not change even through heat treatment, so the nonlinear characteristics do not deteriorate, and the nonlinear characteristic value is high even from a region where the current is as small as 10μA, and the applied voltage is In addition, the leakage current is small, and the increase in leakage current due to the energization time is also small, so the durability is significantly increased.
Clark number of pbo (pb is 1.5 compared to XlO)
Since it uses X10), it has the advantage of being abundant as a resource.

FIG. 1 shows ZnO produced according to an embodiment of the present invention.
Figure 2 shows the voltage-current characteristics of confectionery and the voltage-current characteristics of ZnO confectionery added with Co2O3.
A characteristic diagram showing changes in A/m; FIG. 3 is a voltage-current characteristic diagram of a ZnOi element manufactured according to the second embodiment of the present invention and a ZnO element doped with only Co20,5; FIG.
Non-surface lines of ZnO confectionery manufactured by fixing t2o5 and changing the addition of Co2O3, ZnO confectionery manufactured by changing only the amount of 00203 added, and ZnO confectionery manufactured by changing only the amount of At2o3 added. The exponential characteristic diagram, FIG. 5, was produced according to a third embodiment of the invention. Voltage of ZnO element and ZnO element added with curved lead silicate glass Figure 7 shows the non-linear exponential characteristic diagrams of ZnO confectionery, ZnO confectionery manufactured by changing only the added amount of bent silicate glass, and ZnO confectionery manufactured by changing only the added amount of co203.
A characteristic diagram showing the rate of increase in leakage tL flow in Examples, FIG. 8 shows a ZnOX element manufactured according to the fourth example of the present invention, At2O5, curved silicate glass, and CO2O3.
t-The voltage of each removed ZnO element is shown in the flow tube diagram, and Figure 9 shows the voltage of the ZnO element manufactured by changing the amount of curved borosilicate glass added.
element, by removing At2o5 and changing the amount of glass added, j! ! ! The remaining ZnOiR child, Z manufactured by changing the amount of CO2O3 added with the formulation from which the glass was removed
Figure 1 is a diagram showing the leakage current increase rate characteristic diagram of the fourth example.

Figure 1 Figure 2 CO2O3:6. n [1g Cmo 0/,) Figure 3 Figure 4 CO2O3J,,int(moi'm)Figure 5 Figure 6 70 tons of CO2O3 (moiolo) Figure 7 When charging P Figure 8

Claims (1)

[Claims] (1) After reacting pbo, 8b203' at a predetermined temperature in advance, the reactants f ZnO, MnO2, 5
A method for manufacturing a zinc oxide nonlinear resistor, which comprises adding and mixing B205, Cr2O3, and Co2O3, pressure molding, and heat-treating the molded product. (2) PbO, 5b205 reaction 1h t-0,2 color 20 wt%, MnO2 0.1 to 5 mol%
, 5b2o3 from 0.1 to 5mo1%, Cr2O3k
'O61 to 5 mol '16, Co2O3ft0.
The method for manufacturing a zinc oxide nonlinear resistor according to claim 1, characterized in that 1 to 5 mo1% k ZnOK is added. (3) The molar ratio of PbO and 5b205 is 2=
1 to 2: 1.5. A method for producing a zinc oxide nonlinear resistor according to item 1. (4) After reacting pbO, 5b203 at a predetermined temperature in advance, the reaction product 1 fl ZnO, Mn0z + 8b
203, Cr2O5, Co20y, At2C)
A method for manufacturing a zinc oxide non-linear resistor, which comprises adding and mixing the zinc oxide non-linear resistor in the form of a heat-treated molded product. (5) PbO, 5b205 k O-2 to 20
wt4, MnO2 from 0.1 to 5mol%, 5b2o3
1: 0.1 to 5mo1%, Cr2O3f sail 1 to 5
mol %, Co2O3f 0.1 to 5 mol T
o, Al2O5k 0.2/1000 to 20/1
5. The method of manufacturing a zinc oxide nonlinear resistor according to claim 4, wherein the ZnO is added at 1% by mole of 000 mo1%. (6) The method for producing a zinc oxide nonlinear resistor according to claim 4, wherein the reactants have a molar ratio of pbo and 5b2o5 of 2:1 to 2:1.5. (7) After reacting in advance at a temperature of pbo, 5b2o52, the reactant was mixed with ZnO, MnO2, 5b20
5. Cr2O5*CO2O3* is added to zinc silicate glass, mixed, pressure molded, and the molded product is heat treated and molded [method for use]. (8) 0.2 to 20 wt of the PbO, 5b20s
%, MnO2'j-0,1 to 5 mol%, 5
b205't: 0.1 to 5mall. 0.1 to 5 mol% in Cr2O31, Co2O3
0.1 to 5 mol of zinc silicate glass, 0°0
8. The method for manufacturing a zinc oxide nonlinear resistor according to claim 7, wherein 1 to 5 wt% f is added to ZnO. (9) The molar ratio of PbO and 5b205 is 2:1
Claim 7, wherein the reactant is 2:1.5.
The method for manufacturing the zinc oxide nonlinear resistor described in Section 1. (11) After reacting pbo and 5b2o5 at a sufficient temperature in advance, the reactants 'II' ZnO, MnO2
, 51) 205 + Cr2O5, Co2O3, Al2
1. A method for manufacturing a zinc oxide nonlinear resistor, which comprises adding O5 to zinc silicate glass, mixing the mixture, pressure molding, and heat-treating the molded product. α1) PbO, 5b2o310,2 to 20 wt
%, MnO2 0.1 to 5 mo1%, 5b203 sail 1 to 5 mol (16, Cr2O5f 0.1 to 5 mo1%, Co2O3f 0.1 to 5 mall, A
1205k 0.2/1000 to 20/1000 m
ol %, zinc silicate glass 0. 5 wt% from Ol
11. The method for manufacturing a zinc oxide nonlinear resistor according to claim 10, characterized in that t- is added to ZnO. (12) The proportion of Pb0 and 8b203 is 2 in molar ratio.
The method for manufacturing a zinc oxide nonlinear resistor according to claim 1O, wherein the reactants are in a ratio of :l to 2:1.5.