JPS60140702A - Method of producing sensor - 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 The present invention relates to a sensor made of a sintered body of a metal oxide, and particularly to a method for manufacturing a sensor that is miniaturized and formed uniformly to improve response characteristics.

Generally, the sensor is attached to the crotch area 1'1~1' under a specific atmosphere or environment.
, the changes in resistance and capacitance of the metal oxide sintered body are detected by the electrode surface. The materials used in such sensors generally have a high specific resistance value, and by increasing the electrode area and narrowing the electrode spacing, an element having a practical resistance value can be obtained. Its structure consists of press-molding the metal oxide powder material into a single plate of predetermined dimensions (
After 7 firings and forming electrodes on the front and back sides of the sintered body, so-called disk-type ones or comb-shaped electrodes are formed on a ceramic substrate, the material gold 4 and baroxide is printed using a printing method. The so-called thick film type, which uses a sintered body coated with soil in a film shape and fired, is not known.

However, disc type ones are generally press molded (
In order to make the metal oxide of the material easier to mold,
The granules are granulated into spherical and uniformly sized particles using a spray dryer, etc., and the granules are used as gold μi! ! Press mold using the collar. However, it is difficult to press homogeneously with the Nakarato type, and especially when forming a thin plate (for example, 0.5 mm or less), it is easy to break during pressing and VC deformation when forming. , is suitable for making a relatively small sintered body, and requires a large electrode area to achieve a practical resistance value of 11). Therefore, the electrode spacing becomes wide, and the element shape becomes large, resulting in a small response! ] On the other hand, thick-film type products have the disadvantage of not being able to produce good J1 products using printing methods.
Although it is relatively easy to obtain the strength of the 7-sized ceramic, there is a problem that foreign substances can be diffused into the sintered body during firing because the substrate and the ceramic and the sensor are separated. However, the quality characteristics of the product were very poor.

The present invention has been proposed in view of the above-mentioned circumstances.It is a sensor that has a compact shape by sinking a thin film to fix the electrodes arranged on the sheet, and has good response characteristics and no variations. The present invention provides a method for manufacturing.

Method of manufacturing a sensor according to the present invention/i: A thin film sheet of a metal oxide is prepared, electrodes are arranged on the front surface of the sheet, and then a paste-form of the same composition as the sheet is prepared. ~l'
+I! electrode by printing method using r-metal oxide! 2
A thin film with +Ei is formed to form a molded body and fired, and as it is not press-molded using metal oxide powder etc. as in the past, there is a possibility of damage during molding or firing 11j7.
The transformation with Nori 4C is lc. -1. Although it is necessary to provide an attachment part,
The sensor according to the present invention has 14
Because it can be used as an electrode, the shape is small 1] 1]! 3. Try not to have a foreign substance 1i a month like a ceramic substrate 311, during the diffusion of a foreign substance into a viscous body, etc.: 11!
j will also disappear. In this way, 9-) Rareda sensor υ
Because the heat capacity is small and the sensitive body can be made smaller, the response characteristics are much better than conventional press-molded products.

Next, embodiments of the present invention will be described with reference to the drawings.

Fig. 1 is a block diagram showing the manufacturing process of the sensor of the present invention. The force obtained by lowering the sheet is J = 1/ii-zupζ (f-1 electrodes are arranged on the upper and lower surfaces, and this surface is 1-
[A molding process that forms a film by printing a metal oxide in the form of a paste],
1,) and then sintering the molded body at a predetermined temperature 1:g+'
,′+2.

In the sheet making process 10, after crushing the metal oxide that will be used for the sensor, a few percent of ceramic binder (for example, polyhinyl butyral) is added and kneaded into a slurry, and the film is made to a constant film thickness using a doctor blade method. This is the process of obtaining a sheet of

Here, we will explain how to obtain a sheet with a constant film thickness (by extrusion θ
2. Printing method can also be used.

The molding worker J', 11] arranged the 'ili: electrode on the sheet obtained in step 10, and printed a metal oxide in the form of a paste made of the same silk as the sheet to fix the electrode. : This is the process of forming a coating film. Here, the sheet thickness can be adjusted by stacking multiple sheets according to the thickness of the sensor. In order to facilitate the formation of a thin film on the top surface or -1-bottom surface, the electrode and the thin film sheet can be pressed and integrated.

As a method of coating to form a thin film, there is no problem in applying a paste-like metal oxide by any means other than printing, or coating by dipping.

Under firing (', ',] 2 is a culm in which the molded body is fired at a predetermined temperature suitable for the sensor to be used. ・ Electrodes are placed on the 1 and 1 faces in Figure 2. Fig. 3 is a schematic diagram of a sensor of the present invention in which a t-1 seal is provided and covered with electrodes on the upper and lower surfaces. Here, 1 is the sintered body, 2 is the electrode, and 3d
Metal oxide sort, 4 is metal oxide paste, 5 is 1)
-1- line.

The sensor obtained according to the present invention is l.
11. using laws etc. ) Arrange an electrode on the lower surface of the uniform thin film of the metal oxide (1-1-1-1) on the upper surface dimension/ζ, and fix the electrode using a printing method etc. on this upper surface or downward direction. Since a thin metal oxide film is formed and fired on the sheet, a homogeneous product can be obtained91), and the shape can be miniaturized because there is no need to provide a liffle due to the printing method. I can do it.

Figure 71 shows the method of the present invention.
0.71X 3. An example of the response characteristics of Omm no L+, VO, and ZnO-based ceramic humidity sensors is shown in Figure 5. The response characteristics are clearly improved compared to Response +ll.

3. If the manufacturing method of the present invention is used, the sensor can be made smaller, so the response response of the sensor can be reduced.
A sensor with uniform quality characteristics 11,) has been developed, which makes it possible to provide an extremely useful sensor. The method "k" of the present invention can be widely used not only for manufacturing humidity sensors but also gas sensors and ceramic sensors.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the sensor manufacturing process according to the present invention;
FIG. 2 and FIG. 3 are shown in FIG. 11 is a schematic diagram of a sensor obtained by the method of the present invention, and FIG. 5 is a schematic diagram of a sensor obtained by conventional press forming. 2. Electrode: U Metal oxide sheet 4 Metal oxide paste 5 Li-1. Thread honey 10 Sheet making process 11-- Molding TII''!i! ] 2- Firing Process!] '1 Applicant Nippon Cement Co., Ltd. Agent Patent Attorney Akira Ito

Claims (1)

[Claims] A method for manufacturing a sensor, which comprises disposing a V-shaped electrode on a sheet made of metal oxide powder solidified with a binder, coating at least the electrode with a paste of the metal oxide, and then firing.