JPS5990901A - Method of producing voltage 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 of the Invention] The present invention relates to a voltage nonlinear resistor made of an Fi oxide semiconductor.

Voltage nonlinearity is one of the circuit elements based on semiconductors.
There are antibodies, a typical example of which is Zn0-Bl40.
Varistors using 8-series sintered bodies are known. This type of varistor has non-normal voltage-current characteristics, and as the voltage increases, the resistance rapidly decreases. Because the current increases significantly, it is widely used for absorbing abnormal overvoltage and stabilizing voltage.

By the way, the voltage-current characteristics expressed by the following approximate expression are also evaluated as i and p+ for the characteristic θ of a voltage non-linear resistor.

z=(--)ゝ(However, the work is the varistor (current is flowing, current, V is the applied voltage, OFi constant, α is the non-linear coefficient) Therefore, the general characteristics of the varistor are expressed by two constants, C and tX. It is usually indicated by the voltage Vl at 1 mA instead of C, and emphasis is placed on a large value of α, which is an index indicating voltage nonlinear characteristics. Although it has many features such as good voltage-current characteristics (linear resistor) and the ability to arbitrarily adjust the voltage-current characteristics by controlling the thickness of the element, it has the following inconveniences: In other words, looking at the symmetrical current-voltage characteristics, which can be said to be one of the features of ZnO-BiBOB varistors,
The disadvantage is that the rate of change in the negative direction due to C2, such as impact current, DC load, or temperature cycle, is large, resulting in poor reliability.

[Purpose of the invention]

This invention e" was made in view of the above drawbacks, and is a symmetrical type 11
(An object of the present invention is to provide a method for manufacturing a voltage nonlinear resistor with improved piezo-current properties and reliability.) Voltage nonlinear resistance elements Pχ and P made of a sintered body containing zinc as the main component
The feature is that after being immersed in a solution containing for a predetermined period of time, a heat treatment is performed, and then electrode heating is performed.

The solution contains 0.05 to 5 mol% P and 0 pi.
．． It is preferable that it has 05 to 5 weight t%,
The heat treatment is preferably performed in an oxidizing atmosphere at 300"C to 850C.

[Embodiments of the invention]

The voltage nonlinear resistor according to the present invention can be easily manufactured, for example, by the following method. That is, B is added to the main component ZnO.
12O3 components etc. are added, these are wet-mixed in a bot mill etc., and after drying, a binder such as polyvinyl alcohol is added and blended to give a composition of % 100-100.
Pressure molding is carried out at a pressure of 0 Kf/'cuJ f'l' to obtain a finished molded product in the shape of a disk with a diameter of 20 mm and a thickness of about 21 mm, for example. Next, this molded body is heated to a temperature of, for example, 1100 to 1
A sintered body is obtained by firing at a high temperature of about 400° C. in a 9-atmosphere atmosphere. Both sides of the sintered body thus obtained are polished in parallel. This sintered body, for example, phosphoric acid (H8PO4) 1
Chloroplatinic acid (HBPlat6 ・6
HBO) was converted to P and t, and 1 wz% was impregnated into the melted material. After that, this sintered body was placed in the air for 3
After performing heat treatment in the range of 00° C. to 850° C. and cooling to room temperature, A1 is thermally sprayed on both sides to form a coating, thereby obtaining the required voltage nonlinear resistor. In the present invention, the impregnation step can be carried out by immersing the sintered body in the above solution, but if the area around the solution in which the sintered body is immersed is vacuum-suctioned, the impregnation can be carried out in a short time and can be carried out reliably. .

Examples of the solution containing P and Pi used in the present invention include a solution containing an aqueous solution of phosphoric acid (HBPO4), an aqueous solution of chloroplatinic acid (H2, p, tOJ6.6H$lO), or a solution containing, for example, (09HBPO4). )8P, 0
Organic compounds such as 9H6P and to19 may be dissolved in organic solvents such as ether alcohol and benzene. The concentration of the solution used for the first time is preferably one containing 0.05 to 5 moles of P and 0.05 to 5 moles of P difference.

Furthermore, after impregnating P and Pχ by the above method, heat treatment is performed in air or oxygen atmosphere,
The effect of impregnation can be further enhanced.

This heat treatment temperature is 1 between 300 and 850℃.
It was verified that it is desirable that the temperature at a point does not exceed 850°C.

Next, an example of the present invention will be described, but the sintered body used was oxidized! 11 (Bt4oB component etc. are added to lead (2n0) powder, and the diameter is 2o and the thickness is 2 at a pressure of 100Ky/aA.
Molded into a disc shape and heated in an air atmosphere with the molded body for 120 minutes.
It was fired at 0°C and polished on both sides parallel to each other to a thickness of 1 inch.

(Example 1) A sintered body was impregnated in an aqueous solution of 1 molar phosphoric acid in which chloroplatinic acid of 1 wi% in terms of p and t was dissolved.

Thereafter, heat treatment was performed at 600° C., and a sprayed electrode of A1 was attached to both sides to obtain an oxide voltage nonlinear resistor. For this oxide voltage nonlinear resistor, when a current of 1rnA flows, the applied voltage Vl (V), nonlinearity α ゛, and commercial frequency (50gg)/4a current R (μA) are calculated. Table 1 e and 2 are shown together. Furthermore, the polarity characteristics, that is, the shock large current characteristics and the DC load characteristics were determined as the rate of change in the positive direction and the rate of change in the negative direction, and the results are shown in Table 1.

In addition, in C above, the impact large current characteristic is the rate of change in Vl (A) when a surge current of 500 A is applied 10,000 times, and the DC load characteristic is when a load of 2 W is continuously applied for 500 hours at an ambient temperature of 85°C. The rate of change of vlflI'I after that was determined respectively.For comparison, the case of a voltage 4-t linear resistor made of a conventional ZnO-based sintered body in which P and P are not impregnated (Reference Example 1) )-2. Table 1 shows the case of impregnation in a phosphoric acid water bath solution (Reference Example 2) and the case of impregnation in a chloroplatinic acid aqueous solution (Reference Example 3), respectively.

(Example 2) A sintered body was impregnated in an aqueous solution of 0.05 molar phosphoric acid in which chloroplatinic acid was dissolved at a concentration of 0.05% by weight in terms of Pi. A voltage nonlinear resistor was obtained under the same conditions as in Example 1. The characteristics of this resistor were evaluated under the same conditions as in Example 1, and the results are shown in Table 1C.

(Example 3) The viscosity was impregnated in a 0.04 molty phosphoric acid aqueous solution in which chloroplatinic acid was dissolved at a concentration of 0.04 double phase in terms of Pi. A positive nonlinear resistor was obtained under the same conditions as in Example 1. The characteristics of these two resistors were evaluated under the same conditions as in Example 1, and the results are shown in Table 1.

(Example 4) The sintered body was replaced with Pχ1.5. Chloroplatinic acid with a consistency of 1% Vi% was dissolved and impregnated into an aqueous solution of fc phosphoric acid. A voltage nonlinear resistor was obtained under the same conditions as in Example 1. The characteristics of this resistor were evaluated under the same conditions as in Example 1, and the results are shown in Table 1.

(Example 5) The sintered body was impregnated in an aqueous solution of phosphoric acid with a concentration of O, (J5 times the power of H) in terms of Px. A voltage nonlinear resistor was obtained under the same conditions as in Example 1. Two of these resistors were evaluated for their characteristics under the same conditions as in Example 1. The results are shown in Table 1C.

(Example 6) A sintered body was impregnated in an aqueous solution of 0.05 molty phosphoric acid in which chloroplatinic acid was dissolved with an opening degree of 5 claws N-% in terms of Pχ. A 4-volt linear resistor was obtained under the same conditions as in Example 1. The characteristics of this resistor were evaluated under the same conditions as in Example 1, and the results are shown in Table 1. It was impregnated in a 1 mol ammonium phosphate aqueous solution in which chloroplatinic acid was dissolved.A voltage nonlinear resistor was obtained under the same conditions as in Example 1. Two of these 6 resistors were impregnated under the same conditions as in Example 1. The results of the characteristic evaluation are shown in Table 1.

(Example 8) The sintered body was immersed in a 1 molar aqueous solution of trimethylsulfite in which chloroplatinic acid was dissolved at a concentration of 1 liter in terms of Pi. A voltage nonlinear resistor was obtained under the same conditions as in Example 1. The characteristics of this resistor were evaluated under the same conditions as in Example 1, and the results are shown in Table 1.

(Example 9) Phosphite triether ((cBn6o)B:p) in which cyclopentaplatinum chloride (08H6PiOJ6) with a concentration of 1-fold concentration in terms of Pi was dissolved in a 1 molar aqueous solution of C2 Impregnated. A voltage nonlinear resistor was obtained under the same conditions as in Example 1. Table 1 shows the results of 5-sex testing of this resistor under the same conditions as in Example 1.

(Example 10) The sintered body is converted into Pλ and is 6 times t! Two people were immersed in a 0.1 molar phosphoric acid aqueous solution containing chloroplatinic acid having a concentration of 1. A voltage nonlinear resistor was obtained under the same conditions as in Example 1. The characteristics of this resistor were evaluated under the same conditions as in the examples. It was impregnated into an aqueous solution of 6 molar phosphoric acid in which chloroplatinic acid was dissolved. A positive nonlinear resistor was obtained under the same conditions as in Example 1. The characteristics of these two resistors were evaluated under the same conditions as in Example 1, and the results are shown in Table 1.

-Remains 5- Table 1 As is clear from Table 1, the voltage non-direction resistor according to the manufacturing method of the present invention has a 10% variation in characteristics based on polarity.
The main feature is that it has long-term negative characteristics within the range of 1 and 1. However, it is very important that the fluctuation of the characteristics based on the polarity C2 be small in order to maintain and exhibit the symmetrical piezoelectric characteristics. That is, the life characteristics,
It contributes to the n-axis property of the varistor element, and is extremely important in practical terms from the standpoint of, for example, protecting the varistor's radial path and guaranteeing its function as a lightning arrester.

Note that the phosphorus compound Q1mt is not limited to the phosphoric acid, ammonium phosphate used here, and 10 triethyl phosphorus. In addition, electrode phase separation is limited to A1 sintering, and it is recognized that the same effect can be obtained by using methods such as heat evaporation and Indium evaporation, for example. ing.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a voltage non-1μ wire resistor with a symmetrical box, improved piezo-current characteristics, and improved reliability.

Procedural amendment (voluntary) 1. Display of incident Patent Application No. 57-200411 2. Name of the invention Manufacturing method of voltage nonlinear resistor 3. Person who makes corrections Relationship to the incident: Patent applicant (307) Tokyo Shibaura Electric Co., Ltd. 4. Agent 〒100 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo 1. Detailed description of the invention in the specification 6. Contents of amendment

Claims (1)

[Claims] 1. A voltage non-linear resistance element made of a sintered body containing 2nO as a main component is immersed in a solution containing Pi and P for a predetermined period of time, then subjected to heat treatment, and then attached with electrodes. To use as a percentage 1. A method for manufacturing a positive nonlinear resistor. 2, solution tit p 0.05-5 molti + Pi 0
．． The method for manufacturing a voltage nonlinear resistor according to claim 1, wherein the voltage nonlinear resistor contains 05 to 5 M%. 3. The heat treatment is carried out in an oxidizing atmosphere at 300°C to 850°C.