KR100487204B1 - Microwave dielectric ceramic composition and method for manufacturing the same - Google Patents

Abstract

Disclosed are a high frequency BMT composition and a method for producing the same, which have excellent dielectric constant and quality factor and are sinterable even at relatively low temperatures. The dielectric composition has a chemical composition of Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} (0.01 <x <0.03, 0.01 <y <0.03, 0 <δ <1). The dielectric composition exhibits a temperature coefficient of dielectric constant and small resonant frequency suitable for use in satellite communication, and the value of the quality factor (Q × f), which is a measure of dielectric loss, is much better than that of conventional dielectrics.

Description

High frequency dielectric ceramic composition and method for manufacturing same

The present invention relates to a low loss high frequency dielectric ceramic composition and a method of manufacturing the same, and more particularly, to a high frequency BMT composition capable of sintering at a relatively low temperature while having excellent dielectric constant and quality factor.

Recently, with the development of communication technology, interest in devices operating in the microwave band is increasing. Microwaves have a relatively short wavelength compared to radio waves with frequencies of ㎑ to ㎒, which are used for transmitting and receiving radio and television broadcasts. Therefore, microwaves are used for antennas that require wide bandwidth and high reception and directivity. Therefore, the present invention can be applied to mobile communication such as a mobile phone or a vehicle phone, high frequency digital communication or satellite communication.

Currently, the development of high frequency communication devices has been pursued in the direction of miniaturization, thinning, surface mount device (SMD), high performance high frequency, and low voltage and low power. Dielectric resonators, which operate at low voltages while operating at low voltages, have been researched and developed in various ways such as bandpass filters, duplexers, and voltage controlled oscillators (VCOs).

Conventional dielectrics that can be applied to high-frequency regions include Ba (Zn _1/3 Ta _2/3 ) O ₃ (BZT) or Ba (Mg _1/3 Ta _2/3 ) O ₃ (BMT BaO-ZnO-Ta ₂ O ₅ or BaO-MgO-Ta ₂ O ₅ typified by the empirical formula of) is mainly used. The high frequency dielectric generally has three factors, the dielectric constant (ε _r ), the quality factor (Q × f), and the temperature coefficient (T _cf ) of the resonant frequency. The high frequency dielectric material has a high dielectric constant in the high frequency band. It is required to have a temperature stability of the resonant frequency and a high quality factor, etc. In recent years, a Ba-based composite perovskite represented by Ba (B ' _1/3 B " _2/3 ) O ₃ having the best dielectric properties. Since complex perovskite shows much better properties than other materials in terms of quality factor and temperature coefficient of resonance frequency, it is actively studied as a material for high frequency dielectrics, especially Ba (Mg _1/3 Ta _2/3 ). O ₃ (BMT) is the dielectric constant at a frequency of about 25 10㎓ of about 20,000 and degree of quality factor substantially by having near the resonance frequency temperature coefficient to 0 SHF (Super High frequency) of interest as a material for high-frequency components of the band Focus has been.

A dielectric composition using BMT as described above, a method of manufacturing the same, and a method of manufacturing a dielectric resonator using the same are disclosed in US Pat. No. 6,117,806 to Hitoshi Yokoi et al. In the U.S. patent, ethanol was added to a mixed powder of BaCO ₃ , Ta ₂ O ₅ and MgO, and wet pulverized using a ball mill, and then the slurry was obtained at 1,100 ° C. Calculate time. Subsequently, a dispersant is added and pulverized again, and then subjected to a molding process, followed by sintering at about 1600 ° C. to prepare a dielectric specimen. However, when the BMT undergoes such a high temperature process in order to have a high quality factor, the manufacturing cost thereof is excessively high, which makes it difficult to apply the process.

In order to solve this problem, Korean Laid-Open Patent Publication No. 2000-49524 discloses a low loss high frequency dielectric composition and a method of manufacturing the same, which manufacture a dielectric by sintering BMT at a relatively low temperature. According to the domestic patent, a BMT powder obtained by reacting BaCO ₃ , Ta ₂ O ₅ and MgO and a BaO-Ta ₂ O ₅ binary compound obtained by reacting BaCO ₃ and Ta ₂ O ₅ at about 1100 to 1200 ° C. After mixing in proportion, it is sintered at about 1400-1600 ° C. to prepare a dielectric composition. However, even when molding the dielectric composition, since a separate process of preparing a BaO-Ta ₂ O ₅ binary compound is required, the manufacturing cost and time of the dielectric are increased, so the practical advantages are not large.

In order to solve the above problems, it is necessary to reduce the sintering temperature or improve the dielectric properties of the BMT by using a non-stoichiometric composition such as calcination of BMT in two steps or no addition of MgO or excessive addition of Ba. The method is being tried.

Accordingly, one object of the present invention is to provide a high frequency BMT dielectric composition capable of sintering at a relatively low temperature while having excellent dielectric constant and quality factor.

Another object of the present invention is to provide a method for producing a high frequency BMT based dielectric composition which is particularly suitable for high frequency BMT based dielectric compositions capable of sintering at low temperatures while having excellent dielectric constant and quality factor.

According to the present invention in order to achieve the above object of the present invention, the formula Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} (where 0.01 <x <0.03 0.01 <y There is provided a BMT-based high frequency dielectric composition according to &lt; 0.03 0 &lt;

Preferably, the dielectric composition comprises MgTa _{(2 + y)} O _{6 + δ} and BaCO ₃ consisting of MgO and Ta ₂ O ₅ , wherein MgTa _{(2 + y)} O _{6 + δ} is MgO and Ta ₂ O ₅ is prepared by reacting at a temperature of about 1100 to 1200 ° C. for about ₂ to 12 hours. In this case, the BMT-based high frequency dielectric composition is prepared _by reacting the MgTa _{(2 + y)} O _{6 + δ} and BaCO ₃ for about ₂ to 12 hours at a temperature of about 1100 ~ 1200 ℃, about 1500 ~ 1650 ℃ Sintered at temperature has a quality factor of about 150,000-230,000.

In addition, according to the present invention in order to achieve the above-described other object of the present invention, by reacting MgO and Ta ₂ O ₅ MgTa _{(2 + y)} O _{6 + δ} (0.01 <y <0.03, 0 <δ <1) Forming a powder, reacting the MgTa _{(2 + y)} O _{6 + δ} powder and BaCO ₃ Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) 0 _{3 + δ} (0.01 <x <0.03) forming a powder, and sintering the Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} powder This is provided.

Preferably, the MgTa _{(2 + y)} O _{6 + δ} powder is formed by synthesizing the phase by reacting the MgO and Ta ₂ O ₅ for about 2 to 12 hours at a temperature of about 1100 ~ 1200 ℃ The Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} powder is weighed about 1100 to 1200 ° C. after the MgTa _(2.01) O _{6 + δ} powder and BaCO ₃ are weighed. It is formed by synthesizing the phases by reacting at a temperature of about 2 to 11 hours. At this time, the step of sintering the Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} powder is performed at a temperature of about 1500 to 1650 ° C. for about 5 to 10 hours.

According to the present invention, MgTa _{(2 + y)} O _{6 + δ} is prepared by first adding an excess of Ta ₂ O ₅ , and then Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) by} adding an excess of BaCO _{3 . / 3)} by preparing an O _{3 + δ,} because it can be sintered in BMT powder having excellent dielectric characteristics even at a low temperature of about 1500 ℃, at a much lower cost than the conventional case can be produced BMT-based dielectric compositions . In addition, the composition of Ba (Mg _1/3 Ta _2/3 ) O ₃ is calcined in two steps to obtain a composition represented by Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} . Since it can be manufactured, it is possible to sinter even at low temperatures while maintaining the high quality coefficient value and the temperature coefficient of stable resonance frequency, which are advantages of the BMT dielectric material.

Since BMT has the highest quality factor among microwave dielectrics developed so far, it is a suitable material for communication systems that must operate in the microwave region such as satellite communication. In addition, BMT is known as a material for B-site regularization, and has a cubic perovskite structure before regularization and a hexagonal perovskite structure after regularization. Since the ordering of these B sites ions plays a very important role in improving the microwave properties, much research is being conducted. However, since the heat treatment process is required for a long time at a relatively high temperature for the high sintering temperature and the above-mentioned regularization characteristic of the Ba-based composite perovskite is desired improvement in the future.

Production method of a high-frequency dielectric material composition according to the invention _{MgTa (2 + y) O 6} + (2 + y) δ step of preparing a powder, manufactured MgTa O _{6 + δ} step of preparing a BMT powder using a powder and The BMT powder may be divided into three steps, such as pressing and sintering the prepared BMT powder.

First, in the process of preparing MgTa _{(2 + y)} O _{6 + δ} powder, MgO and Ta ₂ O ₅ as initial raw materials are weighed to suit the composition, and then the temperature is about 1100 to 1300 ° C., preferably about MgTa _{(2 + y)} O _{6 + δ} powder was prepared by synthesizing the phase by reacting at a temperature of 1200 ° C. for about 2 to 12 hours. In this case, 0.001 <y <0.003, and 0 <δ <1.

And then to, in using the produced _{MgTa (2 + y) O 6} + δ powder for producing a BMT powder process, the basis weight of the _{MgTa (2 + y) O 6} + δ powder and BaCO ₃ in an appropriate composition, and then, Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} powder was prepared by synthesizing the phase by reacting at a temperature of about 1100 ° C. to 1200 ° C. for about 2 to 12 hours. Here, 0.01 <x <0.03.

Then, the prepared BMT powder was press-molded and then fired at a temperature of about 1500 ° C to 1650 ° C to prepare a dielectric composition for high frequency.

In accordance with the present invention, Ta ₂ by the addition of excess _{O 5 MgTa (2 + y)} O 6 + _δ for preparing a first, and then here the excess addition of _{BaCO 3 Ba 1 + x (Mg} 1/3 Ta (2+ _{Since y) / 3} ) O _{3 + δ} is produced, the BMT powder can be sintered at a temperature of about 1500 ° C. at a relatively low temperature.

The high frequency dielectric composition prepared according to the present invention has a sintered density of about 97% or more even at a sintering temperature of about 1500 ° C., and exhibits a quality factor (Q × f) of about 150,000 GHz or more. In particular, when sintered at a temperature of about 1650 ℃ depending on the mole ratio of BMT powder showed an excellent quality factor of about 230,000GHz. This excellent quality factor value is about 30,000 GHz higher than that of conventional BMT dielectrics, which is much better than conventional dielectric products. In addition, the high-frequency dielectric composition according to the present invention exhibited excellent quality factor values of about 150,000 GHz or more even when the firing temperature was lowered to a temperature of about 1500 ° C.

As described above, according to the present invention, Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O ₃ by calcining the composition of Ba (Mg _1/3 Ta _2/3 ) O ₃ in two steps. _Since it is manufactured with the composition represented by _{+ δ} , sintering is possible at low temperatures while maintaining the high quality coefficient value and the temperature coefficient of stable resonance frequency, which are advantages of the BMT dielectric material.

Hereinafter, the high frequency dielectric ceramic composition and its manufacturing method according to the present invention will be described in detail with reference to preferred examples of the present invention, but the present invention is not limited or limited by the following examples.

Experimental Example 1

MgO and Ta ₂ O ₅ were initially weighed and then reacted at a temperature of about 1200 ° C. for about 5 hours to synthesize phases to prepare MgTa _(2.01) O _{6 + δ} powder. At this time, it was 0 <δ <1.

Subsequently, the prepared MgTa _(2.01) O _{6 + δ} powder and BaCO ₃ were weighed and then reacted at a temperature of about 1190 ° C. for about 8 hours to synthesize a phase, thereby obtaining Ba _1.01 (Mg _1/3 Ta _{(2.01) / 3} ) O _{3 + δ} powder was prepared.

Next, four specimens were prepared by press molding the prepared Ba _1.01 (Mg _1/3 Ta _{(2.01) / 3} ) O _{3 + δ} powder, and then, each specimen was subjected to 1500 ° C., 1550 ° C., 1600 ° C. and Sintering was performed at 1650 ° C. for about 5 to 10 hours, respectively, to prepare specimens 1, 2, 3, and 4 for the high frequency dielectric composition.

Table 1 below shows the measured values of the sintering temperature, permittivity (ε _r ), density, quality factor (Q × f), and temperature coefficient (T _cf ) of the resonance frequency of the specimens 1 to 4. In Table 1, the dielectric constant (ε _r ) and the quality factor (Q × f) were measured using the Hakki-Coleman method and the resonator perturbation method using the TE11 resonant mode, respectively. The change is measured and shown using a high frequency circuit analyzer.

Sintering Temperature (℃) Permittivity (ε _r ) density(%) Q × f (10㎓) T _cf (ppm / ℃) Psalm 1 1500 24.5 97.0 150,000 2.82 Psalm 2 1550 24.5 97.3 160,000 3.43 Psalm 3 1600 24.5 97.8 168,000 3.44 Psalm 4 1650 24.5 98.3 167,000 3.75

As shown in Table 1, the dielectric composition according to the present experimental example had excellent quality coefficients increasing in the range of 150,000 to 167,000 depending on the firing temperature, and the temperature coefficient of the resonance frequency also showed a value between 2.82 and 3.75.

Experimental Example 2

First, MgO and Ta ₂ O ₅ were weighed and then reacted at a temperature of about 1190 ° C. for about 7 hours to synthesize a phase to prepare MgTa _(2.02) O _{6 + δ} powder. At this time, the range of δ is the same as in the case of Experimental Example 1.

The MgTa _(2.02) O _{6 + δ} powder prepared was weighed with BaCO ₃ , and then reacted at a temperature of about 1190 ° C. for about 6 hours to synthesize a phase, thereby obtaining Ba _1.01 (Mg _1/3 Ta _{(2.02) / 3} ). O _{3 + δ} powder was prepared.

Subsequently, by pressing the prepared Ba _1.01 (Mg _1/3 Ta _{(2.02) / 3} ) O _{3 + δ} powder to prepare specimens 5 to 8, each specimen was subjected to 1500 ° C, 1550 ° C, 1600 ° C, and 1650. The high frequency dielectric composition specimens 5 to 8 were prepared by sintering at a temperature of about 5 to 10 hours, respectively.

Table 2 below shows the measured values of the dielectric constant (ε _r ), the density, the quality factor (Q × f), and the temperature coefficient (T _cf ) of the resonant frequency according to the sintering temperature of the specimens 5 to 8. At this time, the dielectric constant, the quality factor and the temperature coefficient of the resonance frequency were measured in the same manner as in Experimental Example 1 described above.

Sintering Temperature (℃) Permittivity (ε _r ) density(%) Q × f (10㎓) T _cf (ppm / ℃) Psalm 5 1500 24.5 97.0 150,000 2.83 Psalm 6 1550 24.5 97.3 160,000 3.46 Psalm 7 1600 24.5 98.0 185,000 3.43 Psalm 8 1650 24.5 98.4 190,000 3.79

Referring to Table 2, the dielectric composition according to the present Experimental Example has an excellent quality coefficient which increases in the range of 150,000 to 190,000 according to the sintering temperature in the range of 1500 to 1650 ° C, and the temperature coefficient of the resonance frequency is also between 2.83 and 3.79 Excellent value of.

Experimental Example 3

After weighing MgO and Ta ₂ O ₅ , the reaction was performed at a temperature of about 1185 ° C. for about 8 hours to synthesize phases, thereby preparing MgTa _(2.03) O _{6 + δ} powder. At this time, the range of δ is the same as in Experimental Example 1.

The MgTa _(2.03) O _{6 + δ} powder prepared was weighed with BaCO ₃ , and then reacted at a temperature of about 1160 ° C. for about 11 hours to synthesize a phase. Ba _1.01 (Mg _1/3 Ta _{(2.03) / 3} ) O _{3 + δ} powder was prepared.

Subsequently, by pressing the prepared Ba _1.01 (Mg _1/3 Ta _{(2.03) / 3} ) O _{3 + δ} powder to prepare specimens 9 to 12, each specimen was subjected to 1500 ° C, 1550 ° C, 1600 ° C, and 1650. Sintering was performed at a temperature of 5 ° C. for 5 to 10 hours to prepare high frequency dielectric composition specimens 9 to 12.

Table 3 below is a value obtained by measuring the dielectric constant (ε _r ), density, quality factor (Q × f), and temperature coefficient (T _cf ) of the resonant frequency according to the sintering temperature of specimens 9 to 12. In this case, the measurement method of the dielectric constant, the quality factor, and the temperature coefficient of the resonance frequency is the same as in Experimental Example 1 described above.

Sintering Temperature (℃) Permittivity (ε _r ) density(%) Q × f (10㎓) T _cf (ppm / ℃) Psalm 9 1500 24.5 97.0 155,000 2.84 Psalm 10 1550 24.5 97.3 160,000 3.45 Psalm 11 1600 24.5 98.1 195,000 3.46 Psalm 12 1650 24.5 98.5 200,000 3.76

As shown in Table 3, the dielectric composition according to the present Experimental Example has a better quality coefficient than the specimens according to Experimental Example 1 in the range of 150,000 to 200,000 according to the sintering temperature of 1500 to 1650 ℃ range, the resonance frequency The temperature coefficient of was also shown the value between 2.84 and 3.76.

Experimental Example 4

First, after weighing MgO and Ta ₂ O ₅ , and reacted for about 10 hours at a temperature of about 1160 ℃ to synthesize a phase to prepare a MgTa _(2.01) O _{6 + δ} powder. At this time, the range of δ is the same as in Experimental Example 1.

The MgTa _(2.01) O _{6 + δ} powder prepared was weighed with BaCO ₃ , and then reacted at a temperature of about 1180 ° C. for about 9 hours to synthesize a phase. Ba _1.02 (Mg _1/3 Ta _{(2.01) / 3} ) O _{3 + δ} powder was prepared.

Subsequently, by pressing the prepared Ba _1.02 (Mg _1/3 Ta _{(2.01) / 3} ) O _{3 + δ} powder to make specimens 13 to 16, each specimen was subjected to 1500 ° C, 1550 ° C, 1600 ° C, and 1650 ° C. Sintering was carried out at a temperature of 5 to 10 hours for each to prepare high frequency dielectric composition specimens 13 to 16.

Table 4 shows measured values of permittivity (ε _r ), density, quality factor (Q × f), and temperature coefficient (T _cf ) of the resonant frequency according to the sintering temperature of specimens 9 to 12. At this time, the measurement method of the dielectric constant, the quality factor and the temperature coefficient of the resonance frequency is the same as in Experimental Example 1 described above.

Sintering Temperature (℃) Permittivity (ε _r ) density(%) Q × f (10㎓) T _cf (ppm / ℃) Psalm 13 1500 24.5 97.1 150,000 2.87 Psalm 14 1550 24.5 97.3 160,000 3.43 Psalm 15 1600 24.5 98.2 180,000 3.42 Psalm 16 1650 24.5 98.6 210,000 3.70

Referring to Table 4, the dielectric composition according to the present Experimental Example has a better quality coefficient than the specimens according to Experimental Example 1 or Experimental Example 2 in the range of 150,000 to 210,000 depending on the firing temperature, the temperature coefficient of the resonance frequency Excellent values between 2.87 and 3.70 are shown.

Experimental Example 5

MgO and Ta ₂ O ₅ were weighed and then reacted at a temperature of about 1120 ° C. for about 12 hours to synthesize phases to prepare MgTa _(2.02) O _{6 + δ} powder. Here, the range of δ is the same as described above.

After weighing the prepared MgTa _(2.02) O _{6 + δ} powder and BaCO ₃ , and reacted for about 12 hours at a temperature of about 1140 ℃ to synthesize a phase Ba _1.02 (Mg _1/3 Ta _{(2.02) / 3} ) O _{3 + δ} powder was prepared.

_Subsequently , the prepared Ba _1.02 (Mg _1/3 Ta _{(2.02) / 3} ) O _{3 + δ} powder was press-molded, respectively, at temperatures of 1500 ° C., 1550 ° C., 1600 ° C. and 1650 ° C. for 5 to 10 hours, respectively. Sintering to prepare the high frequency dielectric composition specimens 17 to 20.

Table 5 shows measured values of the sintering temperature, permittivity (ε _r ), density, quality factor (Q × f), and temperature coefficient (T _cf ) of the resonance frequencies of the specimens 17 to 20. At this time, the measurement method of the dielectric constant, the quality factor and the temperature coefficient of the resonance frequency is the same as in Experimental Example 1 described above.

Sintering Temperature (℃) Permittivity (ε _r ) density(%) Q × f (10㎓) T _cf (ppm / ℃) Psalm 17 1500 24.5 97.1 180,000 2.83 Psalm 18 1550 24.5 97.3 190,000 3.44 Psalm 19 1600 24.5 98.2 200,000 3.44 Psalm 20 1650 24.5 98.4 220,000 3.73

Referring to Table 5, the dielectric composition according to the present experimental example showed an excellent quality factor compared to the specimens according to the above-described experimental examples in the range of 150,000 to 220,000 depending on the firing temperature. In addition, the temperature coefficient of the resonant frequency was also generally excellent between 2.83 and 3.73.

Experimental Example 6

MgO and Ta ₂ O ₅ were weighed and then reacted at a temperature of about 1190 ° C. for about 4 hours to synthesize phases to prepare MgTa _(2.03) O _{6 + δ} powder. After weighing the prepared MgTa _(2.03) O _{6 + δ} powder and BaCO ₃ , and reacted for about 3 hours at a temperature of about 1195 ℃ to synthesize a phase Ba _1.02 (Mg _1/3 Ta _{(2.03) / 3} ) O _{3 + δ} powder was prepared.

Subsequently, Ba _1.02 (Mg _1/3 Ta _{(2.03) / 3} ) O _{3 + δ} powder was press-molded, and then sintered at temperatures of 1500 ° C., 1550 ° C., 1600 ° C. and 1650 ° C. for 5 to 10 hours, respectively. High frequency dielectric composition specimens 21 to 24 were prepared.

Table 6 below shows the measured values of the sintering temperature, permittivity (ε _r ), density, quality factor (Q × f), and temperature coefficient (T _cf ) of the resonance frequencies of the specimens 21 to 24. At this time, the measuring method of the dielectric constant, the quality coefficient and the temperature coefficient of the resonance frequency is the same as the above-described experimental examples.

Sintering Temperature (℃) Permittivity (ε _r ) density(%) Q × f (10㎓) T _cf (ppm / ℃) Psalm 21 1500 24.5 97.2 200,000 2.87 Psalm 22 1550 24.5 98.0 210,000 3.45 Psalm 23 1600 24.5 98.1 220,000 3.44 Psalm 24 1650 24.5 98.7 230,000 3.79

Referring to Table 6, the dielectric composition according to the present Experimental Example showed a very good quality factor compared to the specimens according to the Experimental Example in the range of 150,000 to 230,000 depending on the firing temperature, the temperature coefficient of the resonance frequency A good value was generally obtained between 2.87 and 3.79.

Experimental Example 7

MgO and Ta ₂ O ₅ were weighed and reacted at a temperature of about 1200 ° C. for about 3 hours to synthesize phases to prepare MgTa _(2.01) O _{6 + δ} powder, and then prepared MgTa _(2.01) O _{6+ δ} basis weight of the powder and BaCO _3, and by reacting at a temperature of about 1130 ℃ for about 12 hours to prepare a composite of the _{Ba 1.03 (Mg 1/3 Ta (2.01} ) / 3) O 3 + δ powder. Subsequently, Ba _1.03 (Mg _1/3 Ta _{(2.01) / 3} ) O _{3 + δ} powder was press-molded, followed by sintering at temperatures of 1500 ° C., 1550 ° C., 1600 ° C. and 1650 ° C. for 5 to 10 hours, respectively. High frequency dielectric composition specimens 25 to 28 were prepared.

Table 7 below shows the measured values of the sintering temperature, permittivity (ε _r ), density, quality factor (Q × f), and temperature coefficient (T _cf ) of the resonance frequency of the specimens 25 to 28.

Sintering Temperature (℃) Permittivity (ε _r ) density(%) Q × f (10㎓) T _cf (ppm / ℃) Psalm 25 1500 24.5 96.8 155,000 2.82 Psalm 26 1550 24.5 97.2 165,000 3.44 Psalm 27 1600 24.5 98.2 190,000 3.47 Psalm 28 1650 24.5 98.4 215,000 3.77

Referring to Table 7, the dielectric composition according to the present experimental example showed excellent quality coefficients in the range of 150,000 to 215,000 depending on the firing temperature, and the temperature coefficient of the resonant frequency was also generally excellent between 2.82 and 3.77. .

Experimental Example 8

MgO and Ta ₂ O ₅ were weighed and reacted at a temperature of about 1120 ° C. for about 12 hours to synthesize phases to prepare MgTa _(2.02) O _{6 + δ} powder, and then MgTa _(2.02) O _{6 + δ} powder BaCO ₃ was weighed and reacted at a temperature of about 1170 ° C. for about 10 hours to synthesize a phase, thereby preparing Ba _1.03 (Mg _1/3 Ta _{(2.02) / 3} ) O _{3 + δ} powder. Subsequently, Ba _1.03 (Mg _1/3 Ta _{(2.02) / 3} ) O _{3 + δ} powder was press-molded, followed by sintering at temperatures of 1500 ° C., 1550 ° C., 1600 ° C. and 1650 ° C. for 5 to 10 hours, respectively. High frequency dielectric composition specimens 29 to 32 were prepared.

Table 8 below measures the sintering temperature, permittivity (ε _r ), density, quality factor (Q × f), and temperature coefficient (T _cf ) of the resonant frequency of the specimens 29 to 32.

Sintering Temperature (℃) Permittivity (ε _r ) density(%) Q × f (10㎓) T _cf (ppm / ℃) Psalm 29 1500 24.5 96.7 180,000 2.88 Psalm 30 1550 24.5 97.3 195,000 3.48 Psalm 31 1600 24.5 98.3 205,000 3.48 Psalm 32 1650 24.5 98.4 220,000 3.79

As shown in Table 8, the dielectric composition according to the present experimental example showed excellent quality coefficients in the range of 150,000 to 220,000 depending on the firing temperature, and the temperature coefficient of the resonance frequency also showed a value between 2.88 to 3.79.

Experimental Example 9

MgO and Ta ₂ O ₅ were weighed and reacted at a temperature of about 1200 ° C. for about 4 hours to synthesize phases to prepare MgTa _(2.03) O _{6 + δ} powder, and then MgTa _(2.03) O _{6 + δ} powder BaCO ₃ was weighed and reacted at a temperature of about 1190 ° C. for about 6 hours to synthesize a phase to prepare Ba _1.03 (Mg _1/3 Ta _{(2.03) / 3} ) O _{3 + δ} powder. Subsequently, Ba _1.03 (Mg _1/3 Ta _{(2.03) / 3} ) O _{3 + δ} powder was press-molded, followed by sintering at temperatures of 1500 ° C., 1550 ° C., 1600 ° C. and 1650 ° C. for 5 to 10 hours, respectively. Thus, high frequency dielectric composition specimens 33 to 36 were prepared.

Table 9 below shows the measured values of dielectric constant (ε _r ), density, quality factor (Q × f), and temperature coefficient (T _cf ) of the resonant frequency according to the sintering temperatures of the specimens 33 to 36.

Sintering Temperature (℃) Permittivity (ε _r ) density(%) Q × f (10㎓) T _cf (ppm / ℃) Psalm 33 1500 24.5 97.0 155,000 2.84 Psalm 34 1550 24.5 97.3 160,000 3.49 Psalm 35 1600 24.5 98.2 200,000 3.49 Psalm 36 1650 24.5 98.3 220,000 3.70

Referring to Table 9, the dielectric composition according to the present experimental example showed an excellent quality factor in the range of 150,000 to 220,000 according to the firing temperature, it can be seen that the temperature coefficient of the resonance frequency also has a value between 2.88 to 3.79. .

According to the present invention, MgTa _{(2 + y)} O _{6 + δ} is prepared by first adding an excess of Ta ₂ O ₅ , and then Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) by} adding an excess of BaCO _{3 . / 3)} by preparing an O _{3 + δ,} because it can be sintered in BMT powder having excellent dielectric characteristics even at a low temperature of about 1500 ℃, at a much lower cost than the conventional case can be produced BMT-based dielectric compositions .

In addition, the composition of Ba (Mg _1/3 Ta _2/3 ) O ₃ is calcined in two steps to obtain a composition represented by Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} . Since it can be manufactured, it is possible to sinter even at low temperatures while maintaining the high quality coefficient value and the temperature coefficient of stable resonance frequency, which are advantages of the BMT dielectric material.

As described above, although described with reference to the preferred experimental examples of the present invention, those skilled in the art various modifications and variations of the present invention without departing from the spirit and scope of the present invention described in the claims below. It will be appreciated that it can be changed.

Claims (10)

BMT based high frequency dielectric composition according to the formula. [Formula] Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} In the above formula, 0.01 <x <0.03, 0.01 <y <0.03, and 0 <δ <1. The dielectric composition for a high frequency BMT system of claim 1, wherein a quality factor (Q × f) of the dielectric composition is 150,000 to 230,000. delete delete delete Reacting MgO and Ta ₂ O ₅ to form an MgTa _{(2 + y)} O _{6 + δ} powder; Reacting the MgTa _{(2 + y)} O _{6 + δ} powder with BaCO ₃ to form Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} powder; And Sintering the Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} powder A method of manufacturing a BMT-based high frequency dielectric composition comprising: wherein, x, y, and δ are 0.01 <x <0.03, 0.01 <y <0.03, and 0 <δ <1, respectively Method for producing a dielectric composition for. The method of claim 6, The MgTa _{(2 + y)} O _{6 + δ} powder is formed by weighing the MgO and Ta ₂ O ₅ , and then reacting at a temperature of 1100 to 1200 ° C. for ₂ to 12 hours to synthesize a phase. Method for producing a dielectric composition for high frequency system. The method of claim 6, The Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} powder is weighed from the MgTa _(2.01) O _{6 + δ} powder and BaCO ₃ , and then at a temperature of 1100 to 1200 ° C. A method for producing a BMT-based dielectric composition for high frequency, characterized in that to form a phase by reacting for 2 to 11 hours. The method of claim 6, The step of sintering the Ba _{1 + x} (Mg _1/3 Ta _{(2 + y) / 3} ) O _{3 + δ} powder is performed at a temperature of 1500-1650 ° C. for 5-10 hours. Method for producing a dielectric composition for. delete