JPS60925B2 - Method for manufacturing oxide semiconductor material for thermistor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an oxide semiconductor material for a thermistor, which has a negative temperature coefficient of resistance and is characterized by containing manganese oxide as a main component and, in particular, containing zirconium oxide.

Conventionally, the manufacturing method of commercially available general-purpose thermistor materials having a negative temperature coefficient of resistance generally involves wet mixing, calcination, and wet pulverization, similar to the manufacturing process of other ceramics.

In addition, when contamination with impurities is extremely objectionable, a solution method has been introduced. Agate cobbles are generally used as the cobblestones for the above-mentioned wet mixing and wet grinding. Furthermore, as oxide compositions for thermistors containing zirconium oxide and manganese oxide as the main component, two-component systems such as "Mn-Z" system, Co-Zr system, Ni-Zr system, and Cu-Zr system are well known. [■Hitachi, Ltd., Collected Papers Commemorating the 20th Anniversary of the Central Research Institute, P30-40, 1960].

The present invention controls the resistivity by containing iron or chromium or iron and chromium in Nm-Ni spinel, and furthermore, as an effect of containing zirconium oxide, the B constant is large compared to the resistivity at room temperature, making the Mn-Ni spinel stable.
- A method for producing Fe-Zr-based, Mn-Ni-Cr-Zr-based, or Mn-Ni-Fe-Cr-Zr-based oxide materials, in which wet mixing and wet pulverization are performed using zirconia balls as cobblestones, and Mn-Ni- Fe-based or Mn-Nj-
It is characterized in that Zr is added to the Cr-based or Mn-Ni-Fe-Cr-based material by abrasion from the zirconia balls.

Examples will be described below.

Commercially available raw materials MhC03, NO and Cr203 were blended so that Mn3Ni:Cr=81.5:17.5:1.0 at%, and this was mixed with l iMhendmdbnsty.
PE (manufactured by Norton, Inc., USA) were used as cobblestones for wet mixing in a ball mill, and after drying these slurries, they were temporarily held at a temperature of 800 qo and wet-pulverized and mixed these calcined products in the above ball mill.

The slurry thus obtained is dried to obtain a "semiconductor material." Here, the amount of Zd added can be controlled by changing the grinding conditions. This final composition ratio was determined by fluorescent X-ray analysis of the scale bodies. * indicates the compound composition ratio Mn:Ni:Cr:Zr〒76
．． 5:17.5:1.0:5.0 (atomic %) As shown in the table above, it is most suitable for systems that contain Zr and require addition of features.

When using agate boulders as in the past, S
The contamination of P2 and Ca○ has a large effect on the properties and poor reproducibility in manufacturing.In addition, investment in equipment is required to convert to a solution method.As described above, the present invention If the manufacturing method is used, conventional equipment can be used and the characteristics can be reproducible, which has a great industrial effect. Characteristic values of commercially available general-purpose thermistors (resistivity: 10Q ~ 1h40; B constant: 100 and K ~ 60
0 to K).

Claims (1)

[Claims] 1. In a sintered mixture of metal oxides, the metal element is 94.6 to 55 atom% of manganese, 5 to 25 atom% of nickel, at least one element selected from the group consisting of iron and chromium. In order to obtain an oxide semiconductor for a thermistor containing 100 at% of at least four or more metal elements, including 0.3 to 10 at% of zirconium and 0.3 to 10 at% of zirconium, zirconia balls are produced in the powder manufacturing process. A method for producing an oxide semiconductor material for a thermistor, the method comprising performing a wet mixing/wet grinding process using cobblestones.