JP2007210840A - Manufacturing method of dielectric ceramic composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a dielectric ceramic composition which is composed of a sintered body of high density having ZnTiO<SB>3</SB>phase. <P>SOLUTION: The manufacturing method comprises producing a sintered body, which includes Zn<SB>2</SB>TiO<SB>4</SB>phase and TiO<SB>2</SB>phase and which includes Zn<SB>2</SB>TiO<SB>4</SB>phase as a main phase, by firing a molded product that is composed of the required composition of raw material powder, producing ZnTiO<SB>3</SB>phase from Zn<SB>2</SB>TiO<SB>4</SB>phase and TiO<SB>2</SB>phase by applying heat energy to the sintered body and changing the main phase of the sintered body into ZnTiO<SB>3</SB>phase. The application of the heat energy can be done by heat treating the sintered body by raising the temperature of the sintered body to the required temperature range and keeping the temperature for the required period of time, or by keeping the temperature of the sintered body in a temperature decreasing process of the firing at the required temperature range and for the required period of time. It is preferable for improving the quality factor that the firing is kept at a temperature range of 900-1,000°C and the application of the heat energy is kept at a temperature range of 750-900°C. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a high frequency dielectric ceramic composition that can be sintered at a low temperature.

  In recent years, in the fields of AV equipment, computer equipment, mobile communication equipment, etc., miniaturization and high performance of products have progressed, and various electronic components used for them have also been miniaturized, high performance, and surface mount devices (SMD). The demand for is increasing. For this reason, the market for laminated components in which various electronic components are configured with electrode conductors in layers is expanding.

  Noble metals such as Au, Pt, and Pd have been used as the internal conductors of these laminated parts. However, Ag or Cu that is relatively cheaper than these conductor materials or an alloy containing Ag or Cu as a main component from the viewpoint of cost reduction. Is changing. In particular, Cu has a large cost reduction effect. However, when Cu is used as the internal conductor, a dielectric material that can be stably fired at a temperature lower than its melting point is required.

As a material that satisfies this requirement, the dielectric ceramic composition of Patent Document 1 is known. This dielectric ceramic composition contains B ₂ O ₃ in a range of 0.1 to 6 wt% in a dielectric ceramic composed of 40 to 90 mol% of TiO _{2 and} 60 to 10 mol% of ZnO. A dielectric ceramic mainly composed of TiO ₂ and ZnO has a high firing temperature of about 1300 ° C. Therefore, when a laminated part is formed using this, a low melting point metal such as Cu is used as an inner conductor. It could not be used. Patent Document 1 discloses that a dielectric ceramic containing TiO ₂ and ZnO as main components contains a glass component containing B ₂ O ₃ or B ₂ O _{3 so} that the melting point of the alloy containing Cu or Cu as a main component is not higher than the melting point. Can be fired.

Japanese Patent No. 3103296

In Patent Document 1, when Cu or an alloy containing Cu as a main component is fired in the vicinity of a temperature at which it can be used as an internal conductor, mainly Zn ₂ TiO ₄ + TiO ₂ (rutile, hereinafter referred to as TiO ₂ ), ZnTiO ₃ + TiO ₂ , Zn ₂ TiO ₄ + ZnTiO ₃ are generated in three phases, and each phase has different dielectric properties. Stabilizing the generated phase is very important for stabilizing the quality of the bandpass filter, for example. Is important.
Among them, the ZnTiO ₃ phase decomposes into a Zn ₂ TiO ₄ phase and a TiO ₂ phase when fired at 945 ° C. or higher (Non-patent Document 1). However, according to Patent Document 1, by containing glass containing CuO and B ₂ O ₃ or B ₂ O ₃ , a Zn ₂ TiO ₄ + TiO ₂ phase is stably generated even at a temperature of about 870 ° C. which is less than 945 ° C. It points out what can be done.

The use conditions of various electronic components have been increased in frequency in the GHz band. In such a high frequency region, the dielectric properties are not sufficient in the Zn ₂ TiO ₄ phase, and higher dielectric properties can be obtained in the ZnTiO ₃ phase. In particular, the Zn ₂ TiO ₄ phase has a significant decrease in quality factor. Then, although it can also be considered to fire at a temperature at which no Zn ₂ TiO ₄ phase is generated, it is difficult to obtain a dense sintered body. When the density of the sintered body is low, there is a concern about insufficient strength when used for various electronic components.
In view of the above background, an object of the present invention is to produce a dielectric ceramic composition comprising a dense sintered body having a ZnTiO ₃ phase as a main phase. Another object of the present invention is to obtain a high quality factor in such a dielectric ceramic composition.

Phase Diagrams for Ceramists, Fig.303, System ZnO-TiO2 by Dulin and Rase

For example, even if the ZnTiO ₃ phase is decomposed into a Zn ₂ TiO ₄ phase and a TiO ₂ phase by firing at a temperature of 900 ° C. or higher, the sintered body is then subjected to a predetermined heat treatment to thereby change the ZnTiO ₃ phase. The present inventors have confirmed that it can be generated. Then, the sintered body ZnTiO _3-phase is generated by the heat treatment, since the firing at high temperatures, it is possible to obtain a dense sintered body.

The present invention has been made on the basis of such examination results. A molded body made of a raw material powder having a predetermined composition is fired to contain a Zn ₂ TiO ₄ phase and a TiO ₂ phase, and a Zn ₂ TiO ₄ phase is obtained. By producing a sintered body as a main phase and applying thermal energy to the sintered body, a ZnTiO ₃ phase is generated from the Zn ₂ TiO ₄ phase and the TiO ₂ phase, and the main phase of the sintered body is ZnTiO _3. It is a manufacturing method of the dielectric ceramic composition characterized by making into a phase.
In the present invention, the application of thermal energy can be a heat treatment in which the sintered body is heated to a predetermined temperature range and held for a predetermined time. In addition, for the application of thermal energy, the sintered body in the temperature lowering process of firing may be held in a predetermined temperature range for a predetermined time.
In the present invention, firing is preferably held in a temperature range of 900 to 1000 ° C, and application of thermal energy is preferably maintained in a temperature range of 750 to 900 ° C.

As described above, according to the present invention, a dielectric ceramic composition composed of a dense sintered body having a ZnTiO ₃ phase can be produced, and a higher quality factor can be obtained.

Hereinafter, the present invention will be described in detail based on embodiments.
In the present invention, first, a fired body having a Zn ₂ TiO ₄ phase as a main phase is obtained. Then, by subjecting this sintered body to heat treatment, the sintered body is made into a sintered body whose main phase is ZnTiO ₃ phase.
According to Non-Patent Document 1, the temperature at which the ZnTiO ₃ phase decomposes into the Zn ₂ TiO ₄ phase and the TiO ₂ phase is 945 ° C. However, actually, the ZnTiO ₃ phase decomposes into a Zn ₂ TiO ₄ phase and a TiO ₂ phase at a temperature lower than this temperature. As shown in the examples described later, in the material added with B ₂ O ₃ for low-temperature firing, the temperature at which the ZnTiO ₃ phase decomposes into the Zn ₂ TiO ₄ phase and the TiO ₂ phase in the range of 860 to 890 ° C. (hereinafter, Simply called decomposition temperature). Therefore, in the present invention, firing is performed at a temperature equal to or higher than the decomposition temperature. The specific firing temperature needs to be appropriately determined depending on the composition of the composition to be fired, etc., but within the composition range described later, it is maintained at a temperature of 900 ° C. or higher, preferably 910 ° C. or higher for a predetermined time. do it. The firing temperature does not need to be higher than necessary, and may be 1000 ° C. or lower, preferably 950 ° C. or lower. The holding time in firing may be about 0.1 to 10 hours, preferably about 0.5 to 5 hours. The firing atmosphere may be in the air.

The sintered body obtained by firing has a Zn ₂ TiO ₄ phase as a main phase. In the present invention, the phase having the highest diffraction line peak by XRD (X-Ray Diffraction) is defined as the main phase. Here, the sintered body obtained by firing includes a TiO ₂ phase in addition to the main phase Zn ₂ TiO ₄ phase. Even if the TiO ₂ phase is included, the Zn ₂ TiO ₄ phase is the main phase as long as the peak of the Zn ₂ TiO ₄ phase is the highest in the XRD diffraction line.

By applying thermal energy to the sintered body having the main phase of the Zn ₂ TiO ₄ phase obtained as described above, the main phase of the sintered body is changed to the ZnTiO ₃ phase. The ZnTiO ₃ phase is generated by the reaction of the Zn ₂ TiO ₄ phase and the TiO ₂ phase with the applied thermal energy. In the present invention, there are at least two forms of applying thermal energy to the sintered body. One is a method of performing a heat treatment for holding a predetermined temperature and a predetermined time on a sintered body for which the firing step has been completed. Hereinafter, this method may be referred to as post-baking heat treatment. Another method is to hold the sintered body at a predetermined temperature for a predetermined time in the temperature lowering process of the sintering step. Hereinafter, this method may be referred to as a temperature lowering heat treatment. Both the post-firing heat treatment and the temperature lowering heat treatment generate a ZnTiO ₃ phase from the Zn ₂ TiO ₄ phase and the TiO ₂ phase contained in the sintered body and provide sufficient thermal energy to make the ZnTiO ₃ phase the main phase. It is common in the point given to.
Although the Zn ₂ TiO ₄ phase and the TiO ₂ phase may remain due to the application of thermal energy, they are included in the present invention as long as the ZnTiO ₃ phase is the main phase.

The post-firing heat treatment is preferably performed in a temperature range of 750 to 900 ° C. When the holding temperature in the heat treatment after firing is less than 750 ° C., if the holding temperature is not maintained for a considerable time, the thermal energy applied to the sintered body is insufficient, and a sintered body having a Zn ₂ TiO ₄ phase as a main phase is obtained. The ZnTiO ₃ phase cannot be changed into a main phase sintered body. In addition, when the holding temperature in the heat treatment after firing exceeds 900 ° C., it is close to the decomposition temperature or higher than the decomposition temperature, so that it is difficult to use the ZnTiO ₃ phase as the main phase of the sintered body. Considering dielectric characteristics, the holding temperature is preferably 810 to 890 ° C, more preferably 840 to 880 ° C. The holding temperature is not limited to maintaining a constant temperature, and the temperature can be varied within the above temperature range. Further, when the holding temperature is varied, even if the temperature is outside the above temperature range, the effect of the present invention can be enjoyed if the holding time within the above temperature range can be secured.

In the heat treatment after firing, a preferable holding time can be set depending on the holding temperature. That is, the holding time can be lengthened when the holding temperature is low, and the holding time can be shortened when the holding temperature is high. For example, when the holding temperature is 800 ° C., the sintered body having the main phase of the Zn ₂ TiO ₄ phase is changed to the sintered body having the main phase of the ZnTiO ₃ phase, and the dielectric characteristics, particularly the quality factor is improved. For this purpose, the holding time needs to be 50 hours or more. In addition, for example, when the holding temperature is 860 ° C., in order to change the sintered body whose main phase is the Zn ₂ TiO ₄ phase into the sintered body whose main phase is the ZnTiO ₃ phase, and to improve the quality factor. In addition, a holding time of about 12 hours is sufficient.

  The atmosphere in which the heat treatment after the baking is performed is not particularly limited, and can be performed in the air similarly to the baking. In addition, the oxygen concentration in the atmosphere in which the heat treatment after firing is performed can be made higher than that in the air. It becomes easy to obtain the effect of the phase change by the heat treatment after firing, and further the improvement of the dielectric properties.

  The conditions for the temperature lowering heat treatment may be basically the same as the heat treatment after firing. However, since the sintered body accumulates thermal energy due to firing, it can undergo phase change and further improve dielectric characteristics by applying mild thermal energy as compared with heat treatment after firing. If the holding temperature is the same, the effect of phase change and further improvement of dielectric properties can be obtained in a shorter time than the heat treatment after firing. For example, in the examples described later, when the holding temperature is 860 ° C., the temperature lowering heat treatment can be obtained by holding for 6 hours and obtaining the same quality factor (Q · f (× GHz)) as the holding for 12 hours of post-firing heat treatment. it can.

  Even in the temperature lowering heat treatment, the holding temperature does not need to be constant. The temperature lowering heat treatment can also be realized by slowing the temperature lowering rate in the above temperature range. In the temperature lowering process of firing, for example, a temperature lowering heat treatment can be performed by lowering the temperature range of 810 to 890 ° C. over 10 hours.

  In the present invention, the step before firing may be performed according to a conventional method. That is, a predetermined raw material powder is wet-mixed and dried and then calcined. The calcining may be held at a temperature range of 800 to 1000 ° C. for 0.1 to 10 hours. After calcining, the mixture is pulverized to a predetermined particle size, granulated, and then pressed into a predetermined shape. Then, the baking mentioned above is performed.

The dielectric ceramic composition obtained by the present invention has a ZnTiO ₃ phase as a main phase. Further, the dielectric ceramic composition may include a Zn ₂ TiO ₄ phase and / or a TiO ₂ phase in addition to the main phase. The dielectric ceramic composition having such a phase structure can be obtained by firing at a relatively low temperature of 860 ° C. or lower, as is apparent from Examples described later. However, the dielectric ceramic composition fired at such a low temperature has a low sintered density.

As a specific composition for obtaining a dielectric ceramic composition having a ZnTiO ₃ phase as a main phase, as described in Patent Document 1, for example, TiO ₂ : 40 to 90 mol%, ZnO: 60 to 10 mol% It can be. A dielectric ceramic mainly composed of TiO ₂ and ZnO can obtain a wide range of arbitrary temperature coefficients by selecting the composition ratio. However, when TiO ₂ exceeds 90 mol%, that is, ZnO is 10 mol. If it is less than%, the temperature coefficient is almost constant, and a wide selection effect cannot be obtained sufficiently. When TiO ₂ is less than 40 mol%, that is, when ZnO exceeds 60 mol%, the temperature coefficient takes a large positive value. However, since the temperature coefficient of the coil element is generally positive, the temperature compensation dielectric It is not useful as a porcelain composition. Preferable amounts of TiO ₂ and ZnO are TiO ₂ : 45 to 80 mol%, ZnO: 20 to 55 mol%, and more preferable amounts of TiO ₂ and ZnO are TiO ₂ : 50 to 60 mol% and ZnO: 50 to 40 mol%.

In the present invention, a part of Zn in the ZnTiO ₃ phase can be replaced with Ba. This substitution of Ba can promote the formation of a ZnTiO ₃ phase, as shown in Examples described later. When a part of Zn is replaced with Ba, BaO is further added to the above composition. In this case, it is preferable to substitute a part of ZnO with BaO within a range of 10 mol% or less. When the amount of substitution increases, the effect of improving the dielectric properties by the heat treatment of the present invention cannot be sufficiently obtained. A more preferable amount of BaO is 0.5 to 5 mol%, and a more preferable amount of BaO is 1 to 3 mol%.

The dielectric ceramic composition having the above composition can be fired at a low temperature by containing B ₂ O ₃ . In this case, the content of B ₂ O ₃ is preferably 0.1 to 6 wt%. When the content of B ₂ O ₃ is less than 0.1 wt%, the firing temperature is not sufficiently lowered, and the firing temperature is equal to or higher than the melting point of Cu or an alloy containing Cu as a main component. In addition, when the content of B ₂ O ₃ exceeds 6 wt%, the acid resistance is weak, and the base is eroded by acid during plating and the dielectric properties deteriorate, which is not preferable. _{Incidentally,} B 2 _{O 3} is the effect can be sufficiently obtained even in _B 2 _{O 3} component vitrified. Examples of the glass containing B ₂ O ₃ as one of the components include ZnO—SiO ₂ —B ₂ O ₃ series, SiO ₂ —B ₂ O ₃ series, Bi ₂ O ₃ —ZnO—B ₂ O ₃ series, and the like. In the present invention, any of these glasses can be used effectively.

TiO ₂ and ZnO were weighed so as to be TiO ₂ : 47 mol% and ZnO: 53 mol%, wet-mixed with a ball mill, and then dried. Next, the dried powder was calcined in the atmosphere at 950 ° C. for 2 hours, and the calcined powder was wet-pulverized with a ball mill until the final average particle size was about 0.1 to 0.3 μm, and then dried. . This powder has a ZnTiO ₃ phase as a main phase.
Next, 0.6 wt% of B ₂ O ₃ was added to the powder, and then wet mixed by a ball mill and then dried. Next, the dried powder is calcined at 800 ° C. for 2 hours in the air, and the calcined powder is wet-pulverized with a ball mill until the final average particle size is about 0.1 to 0.3 μm, and then dried. Thus, a dielectric powder was obtained.

Next, the obtained dielectric powder was granulated to produce granules. This granule was molded at a pressure of 1000 kgf / cm ² to obtain a molded body of 12 mmφ. Next, the molded body was fired in the air at 820 ° C., 845 ° C., 860 ° C., 890 ° C. and 920 ° C. for 2 hours. The obtained sintered body was subjected to a heat treatment (post-sintering heat treatment) held at 800 ° C. for 36 hours in the air.

After sintering and after heat treatment, the phase of each sintered body was identified by XRD (X-Ray Diffraction). The results are shown in FIG. 1 (after sintering) and FIG. 2 (after heat treatment).
As shown in FIG. 1, the phase structures of the sintered bodies having the firing temperatures of 820 ° C., 845 ° C., and 860 ° C. are common in that the ZnTiO ₃ phase is the main phase. However, when the firing temperature is 890 ° C., some peaks indicating the ZnTiO ₃ phase that existed until then disappear, while peaks indicating the ZnTi ₂ O ₄ phase and the TiO ₂ phase can be newly found. The peak showing the ZnTi ₂ O ₄ phase is the highest, and the ZnTi ₂ O ₄ phase constitutes the main phase.
From the above XRD observation results, it can be inferred that there exists a critical temperature between 860 ° C. and 890 ° C. at which the ZnTiO ₃ phase decomposes into a ZnTi ₂ O ₄ phase and a TiO ₂ phase. Next, when FIG. 1 and FIG. 2 are compared, the ZnTiO ₃ phase peak that did not exist before the heat treatment can be confirmed in the heat-treated 890 ° C. and 920 ° C. fired products. This indicates that a ZnTiO ₃ phase was generated from the ZnTi ₂ O ₄ phase and the TiO ₂ phase by heat treatment.

FIG. 3 shows a comparison of XRD charts of sintered bodies that were fired at 920 ° C. and heat-treated at 800 ° C. and 860 ° C. Moreover, the result of having measured the dielectric constant ((epsilon) r) and quality factor (Q * f (* GHz)) after heat processing is shown in FIG. The relative dielectric constant (εr) and the quality factor (Q · f (× GHz)) were measured in accordance with Japanese Industrial Standard “Test Method for Dielectric Properties of Microwave Fine Ceramics” (JIS R1627).
In addition, a sintered body that was fired at 920 ° C., and then a sintered body that was heat-treated at 800 ° C. and 860 ° C., were quantitatively analyzed using a STEM / EDS (Scanning Transmission Electron Microscope / Energy Dispersive X-ray Spectrometer). went. The result is shown in FIG.
As shown in FIGS. 3 and 4, although the ZnTiO ₃ phase can be generated from the ZnTi ₂ O ₄ phase and the TiO ₂ phase even when the heat treatment temperature is about 800 ° C., the quality factor (Q · f (× GHz)) is Remains at a low level. This is due to the presence of distortion or defect in ZnTiO _3-phase, it is understood to not exhibit characteristic of the healthy ZnTiO ₃ phases. That is, the thermal energy to be applied to obtain a high quality factor (Q · f (× GHz)) with the ZnTiO ₃ phase as the main phase is specified by the product of the holding temperature and the holding time.

Next, TiO ₂ and ZnO were weighed to the amounts of the main components shown in Table 1, and a sintered body was obtained in the same manner as above except that the firing temperature, heat treatment temperature and heat treatment time shown in Table 1 were used. About each obtained sintered compact, it carried out similarly to the above, and measured the dielectric constant ((epsilon) r) and the quality factor (Q * f (* GHz)). The results are also shown in Table 1.

  As shown in Table 1, the quality factor (Q · f (× GHz)) improves as the heat treatment temperature after firing increases. When the heat treatment time is 36 hours, at a heat treatment temperature of 820 ° C. or higher, a quality factor (Q · f (× GHz)) exceeding that of the sintered body not subjected to the heat treatment can be obtained. As for the heat treatment time, the quality factor (Q · f (× GHz)) is improved by increasing the heat treatment time. When the heat treatment temperature is 860 ° C., a quality factor (Q · f (× GHz)) exceeding the sintered body not subjected to the heat treatment can be obtained in a heat treatment time of 12 hours or more. Even when the heat treatment temperature is 800 ° C., the quality factor (Q · f (× GHz)) exceeding the sintered body not subjected to the heat treatment can be obtained by increasing the heat treatment time to 60 hours. No. No. 11 is obtained by performing the heat treatment in an oxygen atmosphere, and a quality factor (Q · f (× GHz)) exceeding that of the sintered body not subjected to the heat treatment can be obtained.

TiO ₂ , ZnO and BaO are represented by the composition formula: (Zn _1−x Ba _x ) TiO ₃ (x = 0.005, 0.01, 0.03, 0.05, 0.1, 0.15). After that, the sintered body was obtained in the same manner as in Example 1. The firing temperature was 920 ° C. The phase structure of the obtained sintered body was identified by XRD (X-Ray Diffraction).
The result is shown in FIG. 5. When x = 0.03, a peak indicating a ZnTiO ₃ ((Zn, Ba) TiO ₃ ) phase is observed, and when x is further increased, that is, when the amount of substitution of Ba is increased, ZnTiO ₃ is observed. _{The three} phases ((Zn, Ba) TiO ₃ ) tend to increase. That is, in ZnTiO _3, by replacing a part of Zn in Ba, may facilitate the production of _{ZnTiO 3 ((Zn, Ba)} TiO 3) phase.

A sintered body was obtained in the same manner as in Example 1 except that TiO ₂ , ZnO, and BaO were weighed to the amounts of the main components shown in Table 2 and the firing temperature, heat treatment temperature, and heat treatment time shown in Table 2 were set. . About each obtained sintered compact, it carried out similarly to Example 1, and measured the dielectric constant ((epsilon) r) and the quality factor (Q * f (* GHz)). The results are also shown in Table 2. In Table 2, No. 20, 23, 26 and 29 correspond to x = 0.05 in the above composition formula. Nos. 21, 24, 27, and 30 indicate x = 0.1 in the above composition formula. 22, 25, 28 and 31 correspond to x = 0.15 in the above composition formula.

From Table 2, even when a part of Zn is replaced with Ba, the quality factor (Q · f (× GHz)) tends to be improved when the heat treatment temperature is high or the heat treatment time is long.
When a part of Zn is replaced with Ba, even if the heat treatment temperature is 800 ° C. and the heat treatment time is 12 hours, the quality factor (Q · f (× GHz)) exceeds that of the sintered body not subjected to the heat treatment. Can be obtained. Compared to the example in which a part of Zn is not replaced with Ba, a high quality factor (Q · f (× GHz)) can be obtained by holding in a short time.
Moreover, about the quantity of BaO, since the quality factor (Q * f (* GHz)) is the highest in the case of 2.35 mol%, it is preferable to set it as the addition amount of 1.5-3 mol%.

TiO ₂ and ZnO were weighed so as to be TiO ₂ : 47 mol% and ZnO: 53 mol%. Thereafter, a molded body was produced in the same manner as in Example 1. The molded body was baked in the air at 920 ° C. for 2 hours, and as shown in Table 3, the temperature was kept at a predetermined temperature for a predetermined time. About the obtained sintered compact, the dielectric constant ((epsilon) r) and the quality factor (Q * f (* GHz)) were measured like Example 1. FIG. The results are also shown in Table 3.

  As shown in Table 3, the quality factor (Q · f (× GHz)) can also be improved by holding the sintered body in the temperature-decreasing process at a predetermined temperature for a predetermined time without performing another heat treatment after the baking. . The effect of improving the quality factor (Q · f (× GHz)) becomes more prominent as the holding temperature is higher and the holding time is longer.

The XRD chart after sintering in Example 1 is shown. The XRD chart after the heat processing in Example 1 is shown. 2 shows an XRD chart of a sintered body that was fired at 920 ° C. and heat-treated at 800 ° C. and 860 ° C. in Example 1. FIG. In Example 1, the sintered body subjected to firing at 920 ° C., and then the sintered body subjected to heat treatment at 800 ° C. or 860 ° C. were subjected to simple quantitative analysis by STEM / EDS. The XRD chart after sintering in Example 2 is shown.

Claims (4)

Firing a molded body made of a raw material powder of a predetermined composition to produce a sintered body containing a Zn ₂ TiO ₄ phase and a TiO ₂ phase and having a Zn ₂ TiO ₄ phase as a main phase,
By applying thermal energy to the sintered body, a ZnTiO ₃ phase is generated from the Zn ₂ TiO ₄ phase and the TiO ₂ phase, and the main phase of the sintered body is a ZnTiO ₃ phase. A method for producing a dielectric ceramic composition.   2. The method for producing a dielectric ceramic composition according to claim 1, wherein the application of the thermal energy is a heat treatment in which the sintered body is heated to a predetermined temperature range and held for a predetermined time.   2. The method for producing a dielectric ceramic composition according to claim 1, wherein the application of the thermal energy holds the sintered body in the temperature lowering process of the firing for a predetermined time in a predetermined temperature range. The firing is held in a temperature range of 900 to 1000 ° C.,
The method for producing a dielectric ceramic composition according to any one of claims 1 to 3, wherein the application of the thermal energy is held in a temperature range of 750 to 900 ° C.

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