WO2018182180A1 - Bmw-based high frequency dielectric ceramic material and method for manufacturing same - Google Patents

Abstract

The present invention relates to a dielectric ceramic material for a resonator, a filter, and an oscillator used in a wireless communication system. In particular, provided is a Ba(Mg0.5W0.5)O3-based high frequency dielectric ceramic material having an appropriate dielectric constant and a high quality factor in a high frequency band, and a method for producing the same. For this purpose, in the present invention, Ba(Mg0.5W0.5)O3 was selected as a material with good high frequency dielectric properties wherein barium (Ba) is partly substituted with an alkali metal or an alkaline earth metal element, and to compensate for the same, a +3-valent metal element is quantitatively added to the magnesium (Mg) site. Thus, a high frequency dielectric ceramic material composition with a high quality factor and a stable temperature characteristic is produced. A +5-valent metal element may be quantitatively added to tungsten (W) as needed. According to the present invention as described above, a high frequency dielectric ceramic material is expected to have the effects of having a more suitable dielectric constant, excellent temperature characteristics, and a high quality factor.

Description

WMV high frequency dielectric ceramic material and manufacturing method thereof

The present invention relates to a dielectric ceramic material for resonators, filters, and oscillators used in a wireless communication system. The present invention relates to a Ba (Mg _0.5 W _0.5 ) O ₃ based high frequency dielectric ceramic material having an appropriate dielectric constant in a high frequency band and having a high quality factor. It is to provide a manufacturing method. To this end, the present invention selected Ba (Mg _0.5 W _0.5 ) O ₃ as a good material having high frequency dielectric properties. At this time, to partially replace the alkali metal or alkaline earth metal element in place of the barium (Ba) and + trivalent metal element is added quantitatively in place of magnesium (Mg). Thus, a high frequency dielectric ceramic material composition having a high quality factor and stable temperature characteristics was prepared. If necessary, the +5 valent metal element can be added quantitatively to the tungsten (W) site.

Recently, with the rapid development of the wireless communication industry, microwave dielectric ceramics have been applied to mobile phones, wireless LAN (Local Area Network), GPS (Global Position Satellite), military radar system, Intelligent Transport System (ITS), etc. It is actively applied, and the dielectric ceramics for resonators, filters, and oscillators used in the system require an appropriate dielectric constant (ε _r ), a high quality factor (Q × f), and a temperature coefficient close to zero (τ _f ).

In addition, as the amount of information increases and the communication frequency band saturates due to the development of wireless communication, the use frequency band is further increased, and a high quality high frequency transmission / reception component corresponding thereto is urgently required. Therefore, there is an increasing need for a material having a low dielectric constant ε _r and a higher quality factor Q × f even in a high frequency band.

On the other hand, many kinds of ceramic materials have been developed as dielectric resonators used in the microwave region. For example, Ba (Mg _0.33 Ta _0.67 ) O ₃ (BMT; ε _r = 24, Q × f = 250,000 GHz) and Ba (Zn _0.33 Ta _0.67 ) O _{3, which are} composite perovskites (BZT; ε _r = 29, Q x f = 150,000 GHz) has already been commercialized.

Recently, the basic composition of the present invention Ba (Mg _0.5 W _0.5 ) O ₃ (BMW; ε _r = 21, Q × f = 170,000 GHz) has also been studied a lot, and some commercialization has been achieved.

Ba (Mg _0.5 W _0.5 ) O ₃ (BMW) has a composite perovskite crystal structure and possesses the properties of ε _r = 16.7, Q × f = 42,000 GHz, τ _f = -25 ppm / ° C. The high quality factor (Q × f) of Ba (Mg _0.5 W _0.5 ) O ₃ is due to the 1: 1 regularization of B-site and generally improves the high frequency dielectric properties through the modification of the composition.

Looking at the prior art related to such BMW is as follows.

US Pat. No. 6,835,685B2 (Dec. 28, 2004), Japanese Patent Laid-Open No. 2002-087881 (2002.03.27.), And Chinese Patent No. 1264779C (July 19, 2006) show strontium (Sr) in place of barium (Ba). Substituting 1 to 15 mol% and adding 1 to 10 mol% of rare earth oxides (RE ₂ O ₃ ) are combined to improve dielectric properties.

In addition, US Pat. No. 5,432,135 (1995.07.11.) Controls the composition ratio of the basic elements barium (Ba), magnesium (Mg) and tungsten (W), and as an additive yttrium oxide (Y ₂ O ₃ ), titanium oxide ( Disclosed is a high frequency dielectric ceramic material having improved dielectric properties using TiO ₂ ), manganese oxide (MnO ₂ ), and the like.

In addition, Japanese Patent Laid-Open No. 2000-044338 (2000.02.15.) Discloses Ba (Mg _0.5 W _0.5 ) O _3. In the high frequency dielectric ceramic material, the dielectric properties are changed by substituting a part of strontium (Sr) in place of barium (Ba) and a certain amount of zinc (Zn), nickel (Ni) and cobalt (Co) in place of magnesium (Mg). U.S. Patent No. 5,268,341 (1993.12.07.) Is characterized by improving the temperature coefficient (τ _f ) of the resonant frequency by substituting tantalum (Ta) elements in place of tungsten (W).

In addition, Chinese Patent CN 102765938B (2014.04.02.) Discloses Ba (Mg _0.5 W _0.5 ) O ₃ In the high-frequency dielectric ceramic material, yttrium oxide (Y ₂ O ₃ ) or some rare earth oxides (RE ₂ O ₃ ) and zirconium oxide (ZrO ₂ ) are substituted in place of magnesium (Mg), and manganese oxide (MnO ₂ ) is added to 1 A high frequency dielectric ceramic material having improved dielectric properties by adding mol% in combination is disclosed.

Meanwhile, according to Korean Patent Application No. 10-2017-0041421 (2017.03.31), an alkali metal element such as sodium (Na) is placed in place of barium (Ba) in Ba (Mg _0.5 W _0.5 ) O ₃ high frequency dielectric ceramic material. To quantitatively add + trivalent metal elements such as yttrium (Y) in place of magnesium (Mg) to partially replace and compensate for this, an excellent high frequency dielectric ceramic material composition having a high quality factor is disclosed.

However, the dielectric properties of Ba (Mg _0.5 W _0.5 ) O ₃ based high frequency dielectric ceramic materials disclosed in these prior arts have been shown to change depending on the element or additive to be substituted at each site, especially the temperature coefficient of the resonance frequency. It is greatly affected by the minute change of the crystal structure (crystal structure) due to the employment of other elements, there is a problem that does not solve the problem clearly.

Therefore, in order to improve the temperature coefficient of the dielectric resonance frequency of the dielectric, an appropriate additive is selected in consideration of the substitution element size or valence associated with the crystal structure, and an appropriate amount of high-frequency dielectric ceramic material having a high quality factor and stable temperature characteristics is required. As can be developed, it has come to the present invention.

In addition, due to the full-scale introduction of fifth generation communication, high-quality high-frequency transmission / reception is required in several tens of GHz frequency bands. Therefore, the dielectric constant (ε _r ) is low, the quality factor (Q × f) is high, and the temperature characteristic of the resonance frequency is high. There is a need for a stable high frequency dielectric ceramic material.

The present invention has been made to solve the above-mentioned problems, the present invention has a more appropriate dielectric constant, for example, to achieve a high quality factor of 100,000 GHz or more, preferably 150,000 GHz or more for removing noise and efficient transmission and reception It is an object of the present invention to provide a high frequency dielectric ceramic material capable of retaining the temperature coefficient of the resonant frequency improved to within ± 10ppm / ℃ for the temperature stability of the transmission and reception frequency.

In the present invention, in order to prevent the formation of lattice defects or second phases due to the employment of other elements in Ba (Mg _0.5 W _0.5 ) O ₃ having good high frequency dielectric properties, sodium is placed in place of barium (Ba). In order to replace some of the alkali metal elements such as (Na) and to compensate for them, a combination of compounds having a high quality coefficient by adding an appropriate amount of a + trivalent metal element such as yttrium (Y) to the magnesium (Mg) site, and the barium (Ba) site By adding alkaline earth metal elements (group 2a elements), such as strontium (Sr), to a high frequency dielectric ceramic material composition having excellent temperature characteristics of the resonance frequency was developed.

In addition, it was possible to further enhance these excellent characteristics by adding +5 valent metal elements such as tantalum (Ta) alone or in addition to the tungsten (W) sites.

In order to achieve the above object, the present invention, in the composition of (Ba _1-ab Ma _a Mb _b ) (Mg _0.5-c Mc _c W _0.5 ) O ₃ , Ma and Mb are alkali metals and alkaline earth metals, Mc is + 3 is a metal, a and c are each 0.01 to 0.1, and b is 0.09 to 0.25 to provide a MM-based high frequency dielectric ceramic material.

In the composition, part of W is further substituted by Me, which is a +5 valent metal element, to form a composition of (Ba _1-ab Ma _a Mb _b ) (Mg _0.5-c Mc _c W _0.5-e Me _e ) O ₃ , It is preferable that e is 0.01-0.05.

Ma is a + monovalent alkali metal element represented by Ma ₂ O, and is preferably any one selected from Na, K, and Li.

The Mb is a + divalent alkaline earth metal element represented by MbO, and is preferably any one selected from Sr and Ca.

Mc is a + trivalent lanthanide metal element represented by Mc ₂ O _3, and preferably any one selected from Sc, Y, Sm, Gd, Yb, and Dy or In boron group metal element.

Me is a + 5-valent vanadium group metal element represented by Me ₂ O ₅ , and is preferably any one selected from Nb and Ta.

The Ma and Mb is preferably all added for the purpose of high quality factor.

The Mb and Me is preferably added alone or all for the purpose of temperature characteristics of the resonance frequency.

According to the present invention as described above, it can be expected that the high frequency dielectric ceramic material has a more appropriate dielectric constant, and a high quality factor is realized.

In addition, since the high frequency dielectric ceramic material according to the present invention has a stable temperature coefficient (for example, within ± 10ppm / ℃) it can be expected to exhibit good dielectric properties.

In addition, the high frequency dielectric ceramic material according to the present invention can be expected to have a high-quality high-frequency transmission and reception in the tens of GHz frequency band.

Figure 1 according to an embodiment of the present invention _{(Ba 1 -a- b Ma a Mb} b) (Mg 0 .5- c YcW 0 .5- e Me e) O 3 series according to the Mb content of the high-frequency dielectric ceramic material, This graph shows the change in the temperature coefficient of the resonant frequency.

2 is according to the Mb content of _{(Ba 1 -a- b Ma a Mb} b) (Mg 0 .5- c YcW 0 .5- e Me e) O 3 based high-frequency dielectric ceramic material according to an embodiment of the present invention It is a graph showing the change of the quality factor.

Figure 3 is according to the Me content of the _{(Ba 1 -a- b Ma a Sr} b) according to an embodiment of the present invention (Mg _{0 .5- c} YcW _{.5- 0 e e} Me) O ₃ based high-frequency dielectric ceramic material, This graph shows the change in the temperature coefficient of the resonant frequency.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

In the description of the present invention, terms defined are defined in consideration of functions in the present invention, which may vary according to the intention or custom of a person skilled in the art and the definitions are based on the contents throughout this specification. Will have to be lowered.

Before describing the present invention in detail, it should be noted that an excellent ceramic dielectric requires the following characteristics. In other words, an excellent ceramic dielectric resonator requires proper dielectric constant, high quality coefficient, and temperature coefficient of resonance frequency within ± 10ppm / ℃. In other words, in the case of the temperature coefficient, the more the value converges to 0, the better.

Ceramic material of the present invention was prepared by the following manufacturing method.

As starting materials, BaCO ₃ (purity 99.5%) of SAKAI Chem. Ind. Co., Ltd., Na ₂ CO ₃ (purity: 99.5%) of Samjeon Pure Chemical Industries, Ltd., Japan High Purity Chemical Research Institute (Kojundo Chem. Lab. Co., Ltd) MgO (purity: 99%), Y ₂ O ₃ (purity: 99.9%), SrCO ₃ (purity 99.9%), CaCO ₃ (purity 99.5%), Ta ₂ O ₅ (purity: 99.9%), Nb ₂ O ₅ (purity: 99.9%) and WO ₃ (purity: 99.9%) were used.

Starting materials were weighed according to various examples such as [Table 1] and [Table 2] described below, and then zirconia balls and ethyl alcohol were put into polyethylene containers and mixed for 24 hours.

After the mixed raw materials were dried, the mixed powder was placed in a metal mold having a diameter of 25 mm and uniaxially press-molded, and then calcined at 900 to 1100 ° C. for 10 hours. The calcined molded body was again ball milled by the above mixing method, placed in an oven, and dried at 110 to 120 ° C. for 24 to 48 hours.

Thereafter, the dried powder was placed in a metal mold having a diameter of 15 mm and uniaxially press-molded at a pressure of 50 MPa, followed by sintering. At this time, the sintering temperature and time were 1600-1700 ° C and 1 hour, and the temperature increase rate and the cooling rate up to 1200 ° C were 5 ° C / min.

The shrinkage ratio of the sintered body manufactured by the above method was measured and X-ray diffraction analysis (D / MAX-2500V / PC, Rigaku, Japan) was performed on the powder obtained by pulverizing the sintered body. Among the high frequency dielectric properties, the quality coefficient (Q × f) and the temperature coefficient (τ _f ) were measured by the cavity method, and the dielectric constant was measured by the network analyzer using the Hakki-Coleman method. In addition, the temperature coefficient was used model name R3767CG (Advantest, Japan), the quality coefficient and dielectric constant was used model name E5071C (Keysight, USA).

In the present invention, by adding quantitatively alone or all of the alkaline earth metal elements (group 2a) such as strontium (Sr) to the barium (Ba) site, and + 5-valent metal elements such as tantalum (Ta) to the tungsten (W) site The change of temperature characteristic of the resonant frequency was investigated. In Table 1, the addition of alkaline earth metal elements (group 2a) such as strontium (Sr) to the barium (Ba) site was experimentally summarized. In Table 2, tantalum (Ta) was placed in the tungsten (W) site. Quantitative additions were arranged experimentally.

As shown in Table 1, the results disclosed in Korean Patent Application No. 10-2017-0041421 (2017.03.31.) Were compared with the examples of the present invention as comparative examples. Comparative evaluation object properties were made into sinterability and dielectric properties. In the comparative example, particularly a temperature coefficient lower than −10 ppm / ° C. was observed, which is an undesirable result. Even if the temperature coefficient was recorded within the range of -10 ppm / ° C, the comparative example often showed very low values of the quality coefficient.

number	Composition (mol%)								Shrinkage (%)	ε r	Q × f (GHz)	τ f (ppm / ℃)
	BaO	SrO	Na 2 O		MgO	Y 2 O 3		WO 3
Comparative Example 1	100	0	Na	0	50	Y	0	50	17.53%	17.60	57300	-25.00
Comparative Example 2	97	One	Na	2	48	Y	2	50	24.20%	18.65	271290	-16.42
Comparative Example 3	96	2	Na	2	48	Y	2	50	24.66%	18.65	254909	-13.78
Comparative Example 4	95	3	Na	2	48	Y	2	50	24.40%	18.68	241074	-13.76
Comparative Example 5	94	4	Na	2	48	Y	2	50	23.40%	18.69	251841	-13.74
Comparative Example 6	93	5	Na	2	48	Y	2	50	24.46%	18.89	239341	-13.69
Comparative Example 7	92	6	Na	2	48	Y	2	50	24.40%	19.07	210021	-13.21
Comparative Example 8	91	7	Na	2	48	Y	2	50	24.60%	18.98	196833	-11.93
Comparative Example 9	90	8	Na	2	48	Y	2	50	23.73%	18.98	192519	-11.24
Comparative Example 10	85	15	Na	0	50	Y	0	50	23.87%	19.38	77147	-5.42
Comparative Example 11	80	20	Na	0	50	Y	0	50	24.47%	19.58	72315	0.00
Comparative Example 12	75	25	Na	0	50	Y	0	50	24.13%	19.66	49124	5.36
Comparative Example 13	70	30	Na	0	50	Y	0	50	25.27%	20.25	85866	10.3
Example 1	85	14	Na	One	49	Y	One	50	23.73%	18.89	240413	-5.37
Example 2	85	13	Na	2	48	Y	2	50	24.93%	19.43	203677	-5.41
Example 3	85	12	Na	3	47	Y	3	50	24.33%	19.73	188072	-5.43
Example 4	85	11	Na	4	46	Y	4	50	22.80%	19.36	168124	-5.43
Example 5	80	19	Na	One	49	Y	One	50	24.47%	19.39	193794	0.00
Example 6	80	18	Na	2	48	Y	2	50	25.93%	19.71	161269	2.70
Example 7	80	17	Na	3	47	Y	3	50	24.33%	19.5	162180	2.71
Example 8	80	16	Na	4	46	Y	4	50	23.93%	19.32	150436	2.71
Example 9	75	24	Na	One	49	Y	One	50	25.20%	18.76	189083	5.37
Example 10	75	23	Na	2	48	Y	2	50	25.53%	19.31	162618	5.43
Example 11	75	22	Na	3	47	Y	3	50	24.60%	19.42	156668	8.17
Example 12	75	21	Na	4	46	Y	4	50	23.07%	18.97	148661	5.43

As can be seen from Table 1 above, in terms of shrinkage rate, sintering shrinkage of 20% or more was achieved in both Examples and Comparative Examples, and thus there was no problem in sintering characteristics. On the other hand, the dielectric constant (ε _{r )} in the high frequency dielectric properties does not have a large difference of about 18 to 20, but the temperature coefficient of the resonance frequency is linearly changed according to the strontium (Sr) content as shown in FIG. In addition, it can be seen that it changes in conjunction with the content of sodium (Na) and yttrium (Y). In other words, it was found that the substitution of sodium (Na) and yttrium (Y) together with the strontium (Sr) alone can effectively control the temperature coefficient of the resonance frequency. On the other hand, the quality factor is gradually reduced with strontium (Sr) content as shown in Figure 2 and can be seen to sharply lower at more than 0.25 mol, if not added depending on the content of sodium (Na) and yttrium (Y) It can be seen that the quality factor was greatly increased at 0.01 mol compared with that and then gradually decreased again. Therefore, sodium (Na) and yttrium (Y) should be added at least 0.01 mole, although not shown in the table, it is preferred to add up to 0.1 mole. The same is true for alkali metals other than sodium and yttrium (K, Li, etc.) and + trivalent metal elements (Al, Ga, Gd, Sm, etc.). Therefore, in order to develop a high frequency dielectric ceramic material having a high quality factor (Q × f) and stable temperature characteristics of the resonance frequency, it is substituted with sodium (Na) and yttrium (Y) instead of only strontium (Sr) alone. One can see that it is an efficient solution. Here, when less than 0.01 mole, the change in the temperature coefficient (τ _f ) of the resonance frequency is insignificant, and when it exceeds 0.1 mole, it is not preferable because the deterioration of the quality factor is large. Therefore, there is a critical significance in the above range. If Ca is used instead of Sr, the results are similar. On the other hand, strontium (Sr) is preferably included in the range of 0.09 to 0.25 moles. It can be seen that the change of these properties is shown in conjunction with the substitution component in accordance with the substitution amount, which is associated with the change in the crystal structure according to the ion radius and substitution amount of the substitution element.

number	Composition (mol%)										Shrinkage (%)	εr	Q × f (GHz)	τ f (ppm / ℃)
	BaO	SrO	Na 2 O		MgO	Y2O3		WO3	Me 2 O 5
Comparative Example 1	97	0	Na	One	50	Y	2	49	Ta	One	21.26%	18.77	237188	-23.24
Comparative Example 2	96	0	Na	2	48	Y	4	48	Ta	2	22.00%	19.01	183600	-13.85
Comparative Example 3	95	0	Na	3	48	Y	6	47	Ta	3	22.20%	19.29	174078	-13.96
Comparative Example 4	94	0	Na	4	48	Y	8	46	Ta	4	21.86%	19.65	160964	-10.76
Comparative Example 5	93	0	Na	5	48	Y	10	45	Ta	5	22.53%	18.69	128553	-5.64
Example 1	90	10	Na	0	49	Y	One	49	Ta	One	23.27%	19.75	92627	-9.35
Example 2	90	10	Na	0	48	Y	2	48	Ta	2	23.87%	20.25	116229	-7.06
Example 3	90	10	Na	0	47	Y	3	47	Ta	3	23.20%	20.27	125525	-4.74
Example 4	90	10	Na	0	46	Y	4	46	Ta	4	23.93%	20.87	129157	-2.38
Example 5	90	10	Na	0	45	Y	5	45	Ta	5	23.93%	20.82	123299	0.00
Example 6	85	15	Na	0	48	Y	2	48	Ta	2	22.72%	20.57	124553	4.97
Example 7	85	15	Na	0	46	Y	4	46	Ta	4	22.64%	20.76	126554	5.85
Example 8	90	10	Na	0	48	Y	2	48	Nb	2	22.93%	19.51	124757	-8.21
Example 9	90	10	Na	0	46	Y	4	46	Nb	4	22.93%	20.04	144337	1.19
Example 10	90	10	Na	2	48	Y	4	48	Nb	2	23.54%	20.37	138552	-1.37

As shown in Table 1, Table 2 replaces the barium (Ba) site with only alkaline earth metal elements and replaces the +5 valence vanadium metal element with the tungsten (W) site and compensates the charge. + Trivalent metal elements (Sc, Sm, Gd, Yb, Dy, etc.) are added quantitatively, and the comparative example shows that only the alkali metal is substituted, and as shown in FIG. It can be seen that the number can be effectively controlled. Here, although not indicated, the result is similar even if yttrium (Y) is substituted for the trivalent lanthanide metal element Sc, Sm, Gd, Yb, Dy, or In, which is a boron metal element.

That is, the temperature coefficient of the resonance frequency tends to increase linearly in accordance with the increase of strontium (Sr) and tantalum (Ta), and gradually increases when strontium (Sr) and tantalum (Ta) are added together. In addition, as shown in Table 2, when strontium (Sr) and +5 valent vanadium group metal elements (eg, Nb, Ta) are added together, there is an advantage of minimizing the reduction of the quality factor. Here, it is preferable that the + 5-valent vanadium group metal element maintain the ratio (1-5 mol%) of 0.01-0.05 mol. In the case of less than 0.01 mole, the change in the temperature coefficient τ _f of the resonant frequency is too small, and when it exceeds 0.05 mole, the deterioration of the quality factor is not preferable.

Therefore, the temperature coefficient of the resonant frequency is an important factor in the part design along with the quality factor. In order to compensate for and partially replace the alkali metal or alkaline earth metal element in place of barium (Ba), +3 is added in place of magnesium (Mg). The quantitative addition of metal elements and +5 in the place of tungsten (W) can be seen as a very efficient way to produce high frequency dielectric ceramic material compositions with high quality coefficients and stable temperature characteristics. . The change of these properties can be regarded as a phenomenon associated with the change of crystal structure which is closely related to the ion radius and the substitution amount of the substitution element.

Although the present invention has been described in more detail with reference to the examples, the present invention is not necessarily limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not stabilized by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

Claims (8)

1. In the composition of (Ba _1-ab Ma _a Mb _b ) (Mg _0.5-c Mc _c W _0.5 ) O ₃ , Ma and Mb are alkali metals and alkaline earth metals, Mc is + _trivalent metal, and a and c are respectively 0.01 to 0.1, and b is 0.09 to 0.25.
2. The method of claim 1,

   In the composition, part of W is further substituted by Me, which is a +5 valent metal element, to form a composition of (Ba _1-ab Ma _a Mb _b ) (Mg _0.5-c Mc _c W _0.5-e Me _e ) O ₃ , e is a 0.01-0.05 Hz high frequency dielectric ceramic material.
3. The method of claim 1,

   Ma is a + 1-valent alkali metal element represented by Ma ₂ O, and is any one selected from Na, K and Li.
4. The method of claim 1,

   The Mb is a + divalent alkaline earth metal element represented by MbO, and is any one selected from Sr and Ca.
5. The method of claim 1,

   Mc is a + trivalent lanthanide metal element represented by Mc ₂ O _3, and is any one selected from Sc, Y, Sm, Gd, Yb, and Dy, or an Indium as a boron group metal element. Dielectric ceramic material.
6. The method of claim 2,

   Me is a + 5-valent vanadium group metal element represented by Me ₂ O ₅ , and is any one selected from Nb and Ta.
7. The method of claim 1,

   The Ma and Mb is a high frequency dielectric ceramic material, characterized in that all are added for the purpose of high quality coefficient.
8. The method of claim 2,

   The Mb and Me is a high frequency dielectric ceramic material, characterized in that the addition of all or solely for the purpose of temperature characteristics of the resonance frequency.

Images