JPH08191002A - Barium titanate system semiconductor ceramics and its manufacturing method - Google Patents

Abstract

PURPOSE: To elevate a withstand voltage strength and a ratio of withstand voltage/resistivity by a method wherein a fine material powder uniformly including yttrium being semiconducting agent by wet reaction is used, and also a Y/Ti atomic ratio and a Ba/Ti atomic ratio are strictly controlled. CONSTITUTION: In a barium titanate based semiconductor ceramics having a perovskite crystal structure including yttrium as semiconducting agent, a Y/Ti atomic ratio and a Ba/Ti atomic ratio are within a scope enclosed with ABCD are also a mean grain diameter of semiconductor ceramics is 1 to 2μm, and also a maximum grain diameter is 5μm or less. As a characteristic of semiconductor ceramics, in barium titanate based semiconducting ceramics, a withstand voltage strength is 500V/mm or more, and also resistivity in the withstand voltage strength/room temperature is 5 or more. Thus, it is possible to obtain semiconductor ceramics excellent in practicality at low cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a barium titanate-based semiconductor porcelain and a method for manufacturing the porcelain. The barium titanate-based semiconductor porcelain has a small specific resistance at room temperature, and the resistance increases rapidly when the temperature exceeds a certain temperature (hereinafter referred to as “Tc”).
C characteristic ”), temperature control, current limiting,
Widely used as an element for applications such as constant temperature heat generation.

[0002]

2. Description of the Related Art In the above application, an element having a high withstand voltage that can be used even at a high voltage, that is, a PT having a high withstand voltage
There is a demand for semiconductor porcelain having C characteristics. On the other hand, with the reduction in size and weight of electrical products, there is also a demand for small-sized and low-resistance elements, that is, semiconductor porcelain having a PTC characteristic with low specific resistance at room temperature. Therefore, as the characteristics of the semiconductor porcelain having PTC characteristics, higher withstand voltage strength and specific resistance at room temperature (hereinafter, the specific resistance at room temperature is abbreviated as "specific resistance" unless otherwise specified) are more preferable. Making it low is an important issue.

A barium titanate-based semiconductor porcelain having a PTC characteristic generally has a main component of barium carbonate or oxalate and a titanium oxide or oxalate for the purpose of shifting Tc. And for the purpose of grain control,
If necessary, strontium, lead, or calcium carbonate or oxalate is added, or trace amounts of rare earth elements such as Y and Ce, which are semiconducting agents, and oxides of Nb, Ta, and Sb, and PTC. Oxides such as Mn, Fe, Cr and Cu, which are characteristic improving agents that increase the number of digits of resistance change of characteristics, and various oxides such as Si and Al, which are liquid phase sintering aids, are added and mixed, and calcined, It is obtained by crushing, molding and firing.

However, P obtained by the above conventional method
Barium titanate-based semiconductor porcelain having TC characteristics usually needs to be fired at 1300 ° C. or higher, which widens the grain distribution and produces large grains having a diameter of 5 μm or more. As a result, it has been difficult to obtain a barium titanate-based semiconductor ceramic having PTC characteristics with high withstand voltage strength.

In addition, in manufacturing barium titanate-based semiconductor porcelain having PTC characteristics, if a porcelain having a high withstand voltage strength is to be obtained, the specific resistance tends to be high.
It was very difficult to obtain a porcelain having a low specific resistance despite its high withstand voltage.

When expressed in terms of withstand voltage strength / (room temperature) specific resistance, the value tends to decrease as the withstand voltage strength increases, and when the withstand voltage strength is about 100 to 200 V / mm, the withstand voltage strength / A specific resistance of 10 or more may be obtained, but when the withstand voltage strength exceeds 200 V / mm, it was very difficult to obtain a specific resistance of 10 or more. In particular, when obtaining a porcelain having a withstand voltage strength of 500 V / mm or more, the specific resistance becomes very high, and it is impossible to obtain a withstand voltage strength / specific resistance of 5 or more. It was

For example, in Japanese Unexamined Patent Publication No. 26101/1992, Dy and Sb are mixed in a semiconductor ceramic made of BaTiO ₃ and SrTiO ₃ containing TiO ₂ , SiO ₂ , Al ₂ O ₃ and MnO _2. Therefore, it is attempted to obtain a porcelain having a high withstand voltage strength and a low specific resistance, but the specific resistance is around 50 Ωcm and the withstand voltage strength is around 200 V / mm, which is not yet satisfactory as the withstand voltage strength. , The average grain size is also 6 to 15
It is as large as μm.

Further, in Japanese Patent Publication No. 60-25005, as a starting material, a powder obtained by pulverizing and mixing a complex oxalate of barium and titanium and an oxide of Sb as a semiconducting agent and calcining is used. , Control the calcination conditions and molding pressure,
By firing at 1350 ° C., the relative density is 60-9.
A porcelain having a relatively high withstand voltage strength with an average grain diameter of 5% and an average grain diameter of 1 to 5 μm has been obtained.

However, since the relative density of the porcelain having the highest withstand voltage strength is as low as 78%, there is a problem in the strength of the porcelain. In addition, the specific resistance is 100 Ωcm or more, which is high overall, and because the raw material to be used is not uniform in the semiconducting agent, firing at a high temperature of 1350 ° C. is required, and the grain distribution is 1 to 10 μm. wide. As a result, a value of ratio of withstand voltage strength / specific resistance of less than 5 was not obtained, which had very good characteristics.

[0010]

As described above, a barium titanate-based semiconductor porcelain having a high withstand voltage strength and a PTC characteristic with a low specific resistance has not been obtained. Therefore, an object of the present invention is to provide a barium titanate-based semiconductor porcelain having high withstand voltage strength and PTC characteristics with low specific resistance, and a method for manufacturing the same.

More specifically, the withstand voltage strength is 500 V /
mm or more, and withstand voltage strength / specific resistance of 5 or more, barium titanate-based semiconductor porcelain having excellent PTC characteristics that have never been seen, and further, withstand voltage strength of 500 V / mm or more and withstand voltage strength The object of the present invention is to provide a barium titanate-based semiconductor porcelain having a specific resistance of 10 or more and an unprecedentedly excellent PTC characteristic, and a method for producing the porcelain.

[0012]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to achieve the above object. As a result, yttrium is selected as a semiconducting agent element so that Y is uniformly present as a main component. Barium titanate powder having an average particle size of 0.3 μm or less, which was produced by adding an yttrium compound in the process of synthesizing barium titanate by a wet reaction, was used as a raw material, and the Ba / Ti atomic ratio was Y / T
When the i atomic ratio is strictly limited, a barium titanate-based semiconductor porcelain having a small grain size and a uniform grain distribution, which has the characteristics of the present invention, is 125
The present invention has been accomplished by discovering that it can be obtained at a firing temperature of 0 ° C. or lower, which is lower than the conventional one.

That is, according to the present invention, in a barium titanate-based semiconductor ceramic containing yttrium as a semiconducting agent and having a perovskite type crystal structure, the Ba / Ti atomic ratio and the Y / Ti atomic ratio are ABCD shown in FIG. Within the enclosed range, the average grain diameter is 1 to 2 μm, and the maximum grain diameter is 5 μm or less, the withstand voltage strength is 500 V / mm or more, and the withstand voltage is A barium titanate-based semiconductor ceramic having a strength / specific resistance of 5 or more.

The present invention also includes a barium titanate-based semiconductor ceramic containing yttrium as a semiconducting agent and having a perovskite type crystal structure, wherein the Ba / Ti atomic ratio and the Y / Ti atomic ratio are abcd in FIG. In the enclosed range, the average grain diameter is 1 to 2 μm, and the maximum grain diameter is 5 μm or less, the withstand voltage strength is 500 V / mm or more, and the withstand voltage is It is a barium titanate-based semiconductor ceramic having strength / specific resistance of 10 or more.

Further, in the present invention, a solution or slurry of a titanium compound containing antimony in a Y / Ti atomic ratio of Y / Ti = 0.10 to 0.45% and a barium compound are subjected to a wet reaction, and, if necessary, By calcination, the average particle size is 0.3 μm or less, and the Y / Ti atomic ratio and the Ba / Ti atomic ratio are the same as ABCD in FIG.
A barium titanate powder having a perovskite crystal structure uniformly containing yttrium in a range surrounded by bcd was obtained, and after the powder was molded, the molded body was made to be 1150 to 1150.
The present invention relates to a method for manufacturing a semiconductor porcelain, which comprises firing at 1250 ° C.

The reason why each condition is limited in the present invention is as follows. Y / Ti atomic ratio and Ba /
When the Ti atomic ratio is limited to the range surrounded by ABCD in FIG. 1, a porcelain having a characteristic that the withstand voltage strength is 500 V / mm or more and the withstand voltage strength / specific resistance is 5 or more can be obtained.

Even if yttrium is added uniformly, Ba
Even if the Ti / Ti atomic ratio is controlled, the Y / Ti atomic ratio is 0.10.
If it is less than 0.1%, calcination at 1250 ° C. or less can obtain a porcelain having a small grain diameter of 2 μm or less, but the semiconductivity becomes insufficient and the specific resistance becomes high. Also, 1250 ℃
When fired at a temperature above, the grain size increases,
As a result, high withstand voltage strength cannot be obtained. That is, the withstand voltage strength becomes 500 V / mm or less.

Under the above Ba / Ti atomic ratio conditions, Y
The same applies when the / Ti atomic ratio exceeds 0.45%.
Baking at 50 ° C. or lower results in a small withstand voltage strength / specific resistance ratio of less than 5, and when firing at a temperature over 1250 ° C., the grain size increases and 500 V / mm.
The above high withstand voltage strength cannot be obtained.

If the Ba / Ti atomic ratio is larger than the straight line boundary between BCs in FIG. 1 and the Ti ratio is large, the same problem as in the case where the Y / Ti atomic ratio exceeds 0.45% occurs. Further, even when the Ba / Ti atomic ratio is higher than the linear boundary between AD in FIG. 1 and the ratio of Ba is large, the grain size is small and the compressive strength is 500 v / mm or more by firing at 1250 ° C. or less. However, the semiconductivity is insufficient, the specific resistance becomes high, and the withstand voltage strength / specific resistance becomes less than 5.

The Y / Ti atomic ratio and the Ba / Ti atomic ratio are further limited within the range surrounded by abcd in FIG.
This is because a porcelain having more excellent characteristics can be obtained as compared with the case of being limited to the range surrounded by ABCD in FIG. That is, it is possible to obtain a porcelain satisfying the characteristics that the withstand voltage strength is 500 V / mm or more and the withstand voltage strength / specific resistance is 10 or more.

Next, the semiconductor porcelain of the present invention, particularly the method for producing the yttrium-containing barium titanate powder, which is necessary for obtaining the excellent semiconductor porcelain of the present invention, will be described in detail.

In the production method of the present invention, the solution of a yttrium-containing titanium compound means a solution mixed in units of ions or molecules, such as an aqueous solution of a chloride of titanium and a water-soluble compound of yttrium. An organic solvent mixed solution of titanium alkoxide and yttrium alkoxide can be applied. Specifically, it is an aqueous solution of titanium tetrachloride or a titanium chloride solution partially substituted with a hydroxyl group and yttrium nitrate, and an isopropyl alcohol solution of titanium isopropoxide and yttrium isopropoxide.

The yttrium-containing titanium compound slurry means, for example, a hydroxide or oxide slurry obtained by hydrolyzing a solution of the yttrium-containing titanium compound. Specifically, a yttrium-containing hydrous titanium hydroxide slurry obtained by neutralizing and hydrolyzing an aqueous solution of titanium tetrachloride or a titanium chloride solution partially substituted with a hydroxyl group and yttrium nitrate, such as ammonia, titanium isopropoxide And yttrium isopropoxide in isopropyl alcohol solution to which water is added for hydrolysis to obtain a slurry.

The barium compound in the present invention means a barium hydroxide, an oxide, an inorganic salt, an organic barium compound such as an alkoxide, and the like.

When the solution or slurry of the titanium compound containing yttrium and the barium compound are subjected to a wet reaction, for example, a hydrothermal reaction method, an alkoxide method, a coprecipitation calcination method, etc. can be applied.

The hydrothermal reaction method is a method of obtaining a yttrium-containing barium titanate by subjecting a mixture of the above-mentioned titanium, yttrium and barium compounds to a thermal hydrolysis reaction. At this time, a solution prepared by previously dissolving a water-soluble barium compound such as barium chloride in an aqueous solution of titanium chloride and a water-soluble compound of yttrium may be subjected to a thermal hydrolysis reaction in a strong alkali such as sodium hydroxide. Absent.

The alkoxide method is a method in which an alkoxide of titanium, yttrium, or barium is mixed and dissolved in an organic solvent solution and heated to react.

The coprecipitation calcination method is obtained by, for example, coprecipitating a solution of a water-soluble barium compound such as barium chloride in an aqueous solution of a water-soluble compound of titanium chloride or yttrium with oxalic acid. This is a method of calcining a complex oxalate to obtain yttrium-containing barium titanate.

In the production method of the present invention, in order to make the powder obtained by the above-mentioned wet reaction more uniform, the temperature is temporarily set within a temperature range in which the average particle size does not exceed 0.3 μm due to particle growth. You may bake. Specifically, the calcining temperature range is preferably 600 to 950 ° C.

Further, elements such as Pb, Sr, Ca, Zr, and Sn (called shifter agents), which are usually added for the purpose of Tc shift, and Mn, Cu, B, Si, Li, Na,
It is also possible to add an element such as K, Zn, Ni, Al, or Mg that serves as a property modifying aid within a range that does not impair the properties of the present invention.

As described above, the wet reaction process is used, and the Y / Ti atomic ratio and the Ba / Ti atomic ratio are shown in FIG.
When the barium titanate powder having an average particle size of 0.3 μm or less and having a perovskite crystal structure uniformly containing yttrium, which is obtained by controlling the ABCD of the compound to be within the range indicated by abcd, is 1250 ° C. or less. Semi-conducting by unprecedented low temperature firing, the average grain diameter is 1-2 μm and the maximum grain diameter is 5 μm or less.
It is possible to obtain a porcelain having the characteristics of the present invention, which has a small grain size and is well aligned.

[0032]

The semiconductor porcelain according to the present invention has a low specific resistance even though the withstand voltage strength is as high as 500 v / mm or more, and the withstand voltage strength / specific resistance is 5 or more or even 10 or more. Although it is not clear that it has very excellent properties, yttrium, which is a semiconducting agent, is also used as a reagent for wet synthesis and added during the wet reaction.
Strictly controlling the i atomic ratio and the Ba / Ti atomic ratio to obtain barium titanate having a perovskite-type crystal structure with an average particle size of 0.3 μm or less in which yttrium is uniformly distributed in the powder. Therefore, by using the above-mentioned powder as a raw material, Y is the A site in the ABO ₃ perovskite type crystal structure BaTiO ₃ (A; Ba, B; Ti) even at an unprecedented low temperature of 1150 to 1250 ° C. It is presumed that this is because it was possible to uniformly form a solid solution by substitution so as to be semiconducting and to form grains having a small average diameter of 1 to 2 μm and a very narrow distribution.

[0033]

【Example】

Example 1-17 Titanium chloride aqueous solution (1 as Ti) manufactured by Sumitomo Sitix
6.5 wt% content), yttrium nitrate solution dissolved in nitric acid in advance was added so that the Y / Ti atomic ratio was the content shown in Table 1, and dissolved by stirring. While stirring, further add pure water, dilute 10 times, and then add and mix 5% ammonia water over 3 hours until pH becomes 8,
A neutralization hydrolysis reaction was performed.

The obtained yttrium-containing water-containing titanium hydroxide slurry is suction filtered using a Buchner funnel and washed with water to obtain a yttrium-containing water-containing titanium hydroxide cake, and the cake is converted to TiO ₂ in an amount of 0.7 mol / mol. Pure water was added to form a slurry so that the concentration became l. While stirring the slurry, the reaction system was placed in a nitrogen atmosphere, and B was added.
_{a (OH) 2 · 8H 2} O ( HayashiJunyaku Industries, Ltd., guaranteed reagent)
Was added and mixed so that the Ba / Ti atomic ratio was 1.4, the temperature was raised to the boiling temperature over about 1 hour, and the hydrothermal reaction was carried out at a temperature of 105 ° C. for about 4 hours.

Then, after naturally cooling to room temperature, decantation was repeated, and suction filtration using a Buchner funnel and washing with water were performed. The cake obtained after the reaction is TiO 2.
It was redispersed in pure water so as to have a concentration of 0.7 mol / l in terms of _{2 and} made into a slurry. While stirring this slurry and heating it to 60 ° C. and maintaining it at that temperature, Ba / Ti
For the purpose of adjusting the atomic ratio, each slurry was adjusted to pH 8 to 10 by adding a 10% acetic acid solution, and the state was maintained for 1 hour. Each slurry was suction filtered using a Buchner funnel, washed with water, and dried.

The particle size of the obtained powder was measured with a scanning electron microscope (S-900 manufactured by Hitachi, Ltd.), and the crystal shape was measured with an X-ray diffractometer (RV-300 manufactured by Rigaku Electronics Co., Ltd.). However, in all cases, the barium titanate powder had a cubic perovskite crystal structure with an average particle diameter of 0.07 μm. In addition, the powder is a fluorescent X-ray analyzer (P manufactured by Nippon Phillips Co., Ltd.
W1480) was used for compositional analysis, and the Ba / Ti atomic ratio and the Y / Ti atomic ratio were quantified. The results obtained are shown in Table 1.

The above powders were each further calcined at 800 ° C. for 2 hours to obtain yttrium-containing barium titanate perovskite crystal fine powder having an average particle diameter of 0.1 μm. At this time, the composition of the fine powder was analyzed again using a fluorescent X-ray analyzer, and the Ba / Ti atomic ratio and the Y / Ti atomic ratio were
None of them changed from the values shown in Table 1.

The above-mentioned fine powder is wet pulverized and mixed using a ball mill consisting of resin balls and pots, and polyvinyl alcohol is added as a binder in an amount of 1.0% to the powder, and a fine powder is produced using a spray dryer. Granules were obtained to obtain granulated powder.

The granulated powder was formed into pellets having a diameter of 15 mm and a thickness of 1 mm at a pressure of 1 ton / cm ² . At this time, the composition of the molded body was analyzed again by using a fluorescent X-ray analyzer, but the Ba / Ti atomic ratio and the Y / Ti atomic ratio did not change from the values shown in Table 1.

The above-mentioned molded product is 1100 to 125 in air.
Firing was performed by setting the firing temperature in a temperature range of 0 ° C. in 25 ° C. increments. The holding time at the firing temperature is 2 hours, and the temperature rise is + 300 ° C./hr. , The temperature drop is -200 ℃ / h
r. Under the conditions, each firing porcelain was obtained.

The characteristics of the fired porcelain having various compositions (Ba / Ti atomic ratio, Y / Ti atomic ratio) obtained by the above method were measured and shown in Table 2.

The average grain diameter and the maximum grain diameter in Table 2 were measured by observation with a scanning electron microscope (hereinafter abbreviated as SEM). For the average grain diameter, a straight line was drawn on the SEM photograph at regular intervals, the size of the grain hitting the straight line was measured in 0.1 μm units, and the number was counted (however, the grain was large and the grain was hit twice or more). The number is calculated each time) and the total number is set to about 3000, and the calculation is performed by the following formula. (Sum of grain size measurements) / (Total number of pieces)

The specific resistance ρ and the withstand voltage strength E were measured at 25 ° C. by baking ohmic silver paste on both surfaces of the porcelain to form electrodes, which were used as measurement samples. The withstand voltage strength is represented by measuring the maximum applied voltage value just before the sample is broken and dividing it by the distance between electrodes (thickness: mm) of the sample.

The firing temperature is 1100 to 1250.
The firing temperature of the porcelain having the best characteristics of withstand voltage strength / specific resistance (E / ρ) among the porcelains fired at between ° C is shown.

[0045]

[Table 1]

[0046]

[Table 2]

Comparative Example 1-11 Using the same method as in the Example, it is outside the range surrounded by ABCD in FIG. 1, and the Ba / Ti atomic ratio and the Y / Ti atomic ratio are the values shown in Table 3. A fired porcelain was prepared and the characteristics of each porcelain were measured and shown in Table 4.

[0048]

[Table 3]

[0049]

[Table 4]

From Table 1 and FIG. 1, Examples 2, 3, 5 and 5 are shown.
7, 9 to 11 and 14 are within the range surrounded by abcd of FIG. 1, and Examples 1, 4, 8, 12, 13, 15 to 17 are not within the range surrounded by abcd of FIG. But ABCD
You can see that it is within the range surrounded by. Further, it can be seen from Table 3 and FIG. 1 that Comparative Examples 1 to 11 are not within the range surrounded by ABCD in FIG.

As is clear from Table 2, the average grain size of each example is 1 to 2 μm, and the maximum grain size of 5 μm is not observed at all. In, the grain distributions are very uniform.

Further, the examples of Table 2 and Table 4 which is a comparative example.
As is clear from the comparison between and, the porcelain in the range surrounded by ABCD in FIG. 1 has a characteristic that the specific resistance is low and the withstand voltage strength is high, and further, it is surrounded by abcd in FIG. It can be seen that the porcelain within the above range has a withstand voltage strength E / specific resistance ρ of 10 or more, and is very excellent among them.

Comparative Examples 1 to 7 are AB of FIG. 1 according to the present invention.
The Ba / Ti atomic ratio is out of the range surrounded by the CD, but firing at 1250 ° C or lower does not give a porcelain having sufficient characteristics, resulting in insufficient semiconducting ratio. The resistance becomes high, and the desired characteristics of the present invention cannot be obtained.

Comparative Examples 8 to 11 are the inventions of FIG.
The Y / Ti atomic ratio is outside the range of the present invention with respect to the range surrounded by BCD (Comparative Examples 8 and 9 have a low yttrium content, and Comparative Examples 10 and 11 have a high yttrium content). However, in any case, if the firing temperature is lower than the firing temperature in the table, the semiconductivity becomes insufficient, so that the specific resistance becomes high, and if the firing temperature exceeds the firing temperature in the table, the withstand voltage strength becomes low. Moreover, even at the firing temperature at which the best characteristics shown in the table are obtained, as a result, E / ρ
Is less than 5, the desired characteristics of the present invention cannot be obtained.

[0055]

As described above, a fine raw material powder uniformly containing yttrium as a semiconducting agent by a wet reaction is used, and the Y / Ti atomic ratio and the Ba / Ti atomic ratio are strictly controlled. Withstand voltage strength of 500V / m
The PTC semiconductor porcelain with unprecedented characteristics of m or more and withstand voltage strength / specific resistance of 5 or more is further excellent in withstand voltage strength of 500 V / mm or more and withstand voltage strength / specific resistance of 10 or more. A PTC semiconductor porcelain is obtained.

Therefore, according to the present invention, it is possible to provide a PTC semiconductor porcelain which is more practical than ever, and it is possible to expand the usable range. Also,
To obtain the conventional PTC semiconductor porcelain, it is usually 1300
High temperature firing above ℃ is required, and therefore, the furnace structure that can be used must have a durability of 1400 ℃, so the equipment cost is high, and the consumption of jigs such as wasps and setters is severe. Although the maintenance cost was also high, if the method for manufacturing a semiconductor porcelain of the present invention is applied, firing can be performed at a low temperature of 1250 ° C. or lower, so that the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a range of a Y / Ti atomic ratio and a Ba / Ti atomic ratio in a barium titanate-based semiconductor ceramic of the present invention.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenyo Egami 1-3-47 Funamachi, Taisho-ku, Osaka-shi, Osaka Inside Teika Co., Ltd. (72) Naoto Tsubomoto 1-3-Funamachi, Taisho-ku, Osaka, Osaka No. 47 inside Teika Co., Ltd.

Claims (4)

[Claims] 1. A barium titanate-based semiconductor ceramic having a perovskite type crystal structure containing yttrium as a semiconducting agent, wherein a Y / Ti atomic ratio and Ba / Ti are obtained.
The atomic ratio is within the range surrounded by ABCD in FIG.
And the average grain diameter of the semiconductor porcelain is 1-2 μm,
In addition, the maximum grain diameter is 5 μm or less.
A barium titanate-based semiconductor porcelain having V / mm or more and withstand voltage strength / specific resistance at room temperature of 5 or more. 2. A barium titanate-based semiconductor ceramic having a perovskite type crystal structure containing yttrium as a semiconducting agent, wherein a Y / Ti atomic ratio and Ba / Ti are obtained.
The atomic ratio is within the range surrounded by abcd in FIG.
And the average grain diameter of the semiconductor porcelain is 1-2 μm,
In addition, the maximum grain diameter is 5 μm or less, and the withstand voltage strength is 500 V as a characteristic of the semiconductor porcelain.
/ Mm or more and withstand voltage strength / specific resistance at room temperature of 10 or more, barium titanate-based semiconductor porcelain. 3. Yt in terms of Y / Ti atomic ratio is Y.
/Ti=0.10 to 0.45% of the titanium compound solution or slurry is wet-reacted with the barium compound, and calcined if necessary, so that the average particle size is 0.3 μm or less, and Y / Ti atomic ratio and Ba / Ti
A barium titanate powder having a perovskite crystal structure uniformly containing yttrium and having an atomic ratio in the range surrounded by ABCD in FIG. 1 was obtained, and the powder was compacted. The method for manufacturing a semiconductor porcelain according to claim 1, wherein firing is performed at a temperature of ℃. 4. A yttrium-containing titanium hydroxide compound or oxide obtained by hydrolyzing an aqueous solution of a chloride of yttrium and a water-soluble compound of yttrium, wherein the yttrium-containing titanium compound is obtained. 4. The method for producing a semiconductor porcelain according to claim 3, wherein the barium compound is a hydroxide of barium, and the wet reaction is a hydrothermal reaction.