JP3905993B2 - High frequency dielectric ceramic composition and laminated part using the same - Google Patents

Description

【００４５】
この表１から、本発明の誘電体磁器は、比誘電率が１９〜５２、Ｑｆ値が２００００〔ＧＨｚ〕以上の優れた誘電特性を有するとともに、７７０〜８３０℃で焼結収縮が開始し、９２０℃以下で焼成が可能な優れた焼結性を有していることが判る。
【００４７】
尚、アルカリ金属としては、試料番号８でＫを、試料番号１０でＮａを用い、その他はＬｉを用いた。また、アルカリ土類金属としては、試料番号４０でＢａを、試料番号４１でＳｒを用い、その他ではＢａとＣａを用いた。この際ＢａＯとＣａＯの重量比を１：１とした。特に、試料番号４０（Ｂａ）と試料番号１８、４１（Ｓｒ）との比較より、アルカリ土類金属にＢａのみを用いた場合、Ｑｆ値が３００００〔ＧＨｚ〕と非常に良好な値が得られる。
【００４８】
図２中の多角形の線分ａ−ｂの外の試料（試料番号２１、２２）あるいは、線分ｃ−ｄの外の試料（試料番号２３）では、Ｑ値の低い結晶相であるＬａ_２Ｔｉ_２Ｏ_７が形成されてしまい、その結果、Ｑｆ値が２５００、５０００、５０００〔ＧＨｚ〕と非常に低下してしまう。
【００４９】
また、図２中の多角形の線分ｄ−ｅの外の試料（試料番号２５、２６）あるいは、線分ｅ−ａの外の試料（試料番号２７）では、粒界形成成分と反応してしまい、収縮開始温度や焼結温度が高温化したり、Ｑｆ値が実用レベルに達しなくなる。
【００５０】
また、図２中、多角形ｆ、ｇ、ｈ、ｉ、ｊ、ｋ、ｆで囲まれる領域（試料番号１２、１３、１４、１５、１６、１７、１８、１９、２０）では、比誘電率が２０〜３０、Ｑｆ値が２５０００〔ＧＨｚ〕以上の優れた誘電特性を有するとともに、７７０〜８００℃で焼結収縮が開始し、９００℃以下で焼成が可能な優れた焼結性を有する高周波用誘電体磁器を得ることができる。
【００５１】
上述の高周波用誘電体磁器組成物からなる誘電体層を用いて、基体１を構成し、その内部にＡｇやＣｕなどの導電率に優れた導体材料でマイクロストリップライン、容量電極などの高周波動作を行なう内部導体２を形成することができる。
【００５２】
しかも、内部導体２と誘電体層１ａ〜１ｄとを、ＡｇやＣｕの融点に達することのない焼成温度（９２０℃以下）で同時に焼成処理でき、しかも、磁器の収縮開始温度も内部導体２の導体材料の焼結反応の開始と近似させることができるため、基体１にソリが発生しない積層部品が得られる。
【００５３】
なお、外部導体３も、基体１と当然同時に焼成処理することも可能となる。
【００５４】
【発明の効果】
本発明の高周波用誘電体磁器組成物によれば、高周波領域において２００００〔ＧＨｚ〕以上のＱｆ値を有するため高周波部品や基板の小型・高性能化が実現できるとともに、焼成温度を９２０℃以下、収縮開始温度を８３０℃以下とすることが可能となる。
【００５５】
このため、ＡｇやＣｕ等の導体材料と同時に焼成でき、その際導体金属の収縮挙動のミスマッチから発生する基板の反りや歪みが抑制される積層部品となる。
【図面の簡単な説明】
【図１】本発明にかかる積層部品の一例、たとえば共振器の断面図である。
【図２】本発明の高周波用誘電体磁器組成物のｘ、ｙ、ｚの各モル比率の関係を示す三元図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a high frequency dielectric ceramic having a high Q value in a high frequency region such as a microwave and a millimeter wave, and a laminated body. For example, the present invention relates to various resonances used in a high frequency region such as a microwave and a millimeter wave. The present invention relates to a dielectric ceramic composition for high frequency that can be used for a ceramic material, a dielectric substrate material for MIC, a dielectric waveguide material, a dielectric layer of a multilayer ceramic capacitor, and a multilayer component using the same.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, dielectric ceramics are widely used for dielectric resonators, MIC dielectric substrates, waveguides, and the like in high frequency regions such as microwaves and millimeter waves. In recent years, with the development and spread of mobile communications such as mobile phones, the demand for dielectric ceramics as materials for electronic circuit boards and electronic components is increasing.
[0003]
In the simultaneous firing of dielectric ceramics and internal conductors in electronic circuit boards and electronic parts, the firing temperature of conventional dielectric ceramics is as high as 1100 ° C. or higher, so the conductor material has a relatively high melting point. Pt, Pd, W, Mo, etc. were used. Since these high melting point conductor materials have a large conduction resistance, the conventional electronic circuit board has a problem that the Q value of the resonance circuit and the inductance is reduced, and the transmission loss of the conductor line is increased.
[0004]
Thus, in order to solve such problems, low-temperature fired dielectric ceramics that can be fired simultaneously with Ag, Cu, etc. having a low conduction resistance have been proposed. For example, the dielectric ceramic composition disclosed in Japanese Patent Application Laid-Open No. 8-208330 filed earlier by the present applicant is composed of MgO, CaO, TiO ₂ and B ₂ O ₃ , Li ₂ CO ₃ . It can be fired simultaneously with the inner conductors such as Ag and Cu at a relatively low temperature of 900 to 1050 ° C., the dielectric constant εr of the dielectric ceramic is 18 or more, the Q value at the measurement frequency of 7 GHz is 2000 or more, and the temperature coefficient of the resonance frequency It has excellent characteristics with τf within ± 40 ppm / ° C., and can realize miniaturization and high performance of high-frequency electronic components.
[0005]
Moreover, the dielectric ceramic composition disclosed in Japanese Patent Application Laid-Open No. 9-315859 is made of CaO, ZrO ₂ and B ₂ O ₃ , and an alkali metal compound, and can be fired at a relatively low temperature of 1200 ° C. or lower.
[0006]
[Problems to be solved by the invention]
However, since the dielectric ceramic composition disclosed in JP-A-8-208330 has a high sintering temperature and the shrinkage start temperature in sintering is as high as 845 to 960 ° C., the shrinkage behavior with the conductor material. There are problems such as poor matching, and the fired substrate and electronic parts are warped and distorted.
[0007]
The dielectric ceramic composition disclosed in JP-A-9-315859 also has the same problem.
[0008]
That is, as a conductor, there is a conductor mainly composed of Ag and / or Cu, for example, a conductor obtained by adding a metal such as a glass component, a ceramic component, Pt, or Pd to Ag, Cu, or Ag, Cu. Since these conductors have a shrinkage start temperature of about 650 ° C. at the highest at the time of firing, there is a large difference from the shrinkage start temperature of the dielectric ceramic composition, thereby causing problems such as deformation of the substrate and the like. there were.
[0009]
The present invention has been made in view of the above problems, and can lower the shrinkage start temperature to approach the shrinkage start temperature of the conductor. Even when co-fired with a conductor containing Ag or Cu as a main component, warping and distortion can be achieved. An object of the present invention is to provide a high-frequency dielectric ceramic and a laminate that can be suppressed.
[0010]
[Means for Solving the Problems]
The dielectric ceramic for high frequency of the present invention is a composite oxide containing at least Mg, La, and Ti as metal elements, and the composition formula based on these molar ratios is expressed as xMgO · yLa ₂ O ₃ · zTiO ₂ the x, y, z of _{La 4 Ti 9 O 24, MgTi} 2 O 5 and _La 0.66 _{TiO 2.993} with in the range surrounded by the following points a-b-c-d- e-a When the main component having at least one of the main crystal phases and the composition formula by weight ratio are expressed as 1B ₂ O ₃ · mA ₂ O · nSiO ₂ · oRO, the l, m, n, and o are:
40 ≦ l ≦ 90
8 ≦ m ≦ 20
1 ≦ n ≦ 20
1 ≦ o ≦ 20
l + m + n + o = 100
A: At least one of alkali metals
R: At least one of alkaline earth metals
Consists of a grain boundary phase-forming component consisting of, with respect to the main component as 100 parts by weight, the grain boundary phase-forming component is 5 to 30 parts by weight. Where a, b, c, d, e are
Point a (x = 35.5, y = 0.5, z = 64.0)
Point b (x = 16.0, y = 16.0, z = 68.0)
Point c (x = 1.0, y = 20.0, z = 79.0)
Point d (x = 0.5, y = 14.5, z = 85.0)
Point e (x = 27.5, y = 0.5, z = 72.0)
x + y + z = 100
It is. In such a high-frequency dielectric ceramic, it is desirable that the Qf value represented by the product of the Q value and the measurement frequency be 20000 [GHz] or more.
A dielectric ceramic composition for high frequency, characterized by being based on 100 parts by weight of a main component.
[0011]
R is preferably Ba.
[0012]
Also, a laminated part having a conductor mainly composed of Ag and / or Cu on the inside and surface of a substrate formed by laminating a plurality of dielectric layers, wherein the dielectric layer is a dielectric ceramic composition for high frequency as described above It is a laminated part made of objects.
[0013]
[Action]
The dielectric ceramic for high frequency according to the present invention has a firing temperature of 940 ° C. or less without significantly deteriorating the dielectric properties of the ceramic filler itself due to the grain boundary phase forming component containing B, alkali metal, Si and alkaline earth metal. The sintering start temperature can be set to 830 ° C. or less, and the sintering behavior of the substrate and the sintering behavior of the inner conductor such as Ag and Cu can be achieved even when the inner conductor such as Ag and Cu is simultaneously fired. It can be approximated and the warpage of the substrate can be prevented.
[0014]
Furthermore, the Qf value of the porcelain represented by the product of the Q value and the measurement frequency becomes 15000 [GHz] or more, and the resonator material, the dielectric substrate material for MIC, the dielectric waveguide material, the multilayer ceramic capacitor It can be suitably used for a dielectric layer or the like.
[0015]
Further, the grain boundary phase forming component has a compositional formula by weight ratio of 1B ₂ O ₃ · mA ₂ O · nSiO ₂ · oRO (A is at least one of alkali metals, and R is at least one of alkaline earth metals). When l, m, n, and o satisfy 40 ≦ l ≦ 90, 8 ≦ m ≦ 20, 1 ≦ n ≦ 20, 1 ≦ o ≦ 20, l + m + n + o = 100, It can be fired at the firing temperature, the firing shrinkage start temperature can be 830 ° C. or less, can be close to the shrinkage start temperature of a conductor mainly composed of Ag and / or Cu, and Ag and Cu are the major components. Even when fired simultaneously with the conductor, the occurrence of warpage, distortion, etc. of the substrate and electronic components can be suppressed, and the Qf value becomes 20000 (GHz) or more.
[0016]
Further, in the above-described dielectric ceramic composition, since the above-mentioned dielectric ceramic composition can be fired at a relatively low temperature of 940 ° C. or lower, the inner or surface conductor has excellent conductivity such as Ag and Cu, and excellent high frequency characteristics. In addition, since the sintering behavior can be approximated even when integrally fired, a laminated part can be achieved without generating warp or the like on the substrate.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a high frequency dielectric ceramic composition of the present invention and a laminated part using the same will be described in detail with reference to the drawings.
[0018]
FIG. 1 is a cross-sectional view of a multilayer component according to the present invention. For example, a triplate multilayer resonant component is shown as an example. In the figure, reference numerals 1a to 1d denote dielectric ceramics for high frequency (simply referred to as dielectric layers). An inner conductor 2 is provided inside a laminate (base) 1 composed of the dielectric layers 1a to 1d, and a surface conductor 3 is provided on the surface. Is formed.
[0019]
The dielectric layers 1a to 1d are composite oxides containing at least Mg, La, and Ti as metal elements, and at least one of La ₄ Ti ₉ O ₂₄ , MgTi ₂ O _5, and La _0.66 TiO _2.993 is a main crystal. A dielectric ceramic comprising a main component as a phase and a grain boundary phase-forming component containing B, alkali metal, Si and alkaline earth metal.
[0020]
The inner conductor 2 is made of a conductor film containing Ag or Cu as a main component, and the inner conductor 2 is formed in a direction penetrating between the dielectric layers 1a to 1d and through the thickness of the dielectric layers 1a to 1d. For example, in a resonant component, a microstrip line operates between the dielectric layers 1b and 1c, and one end (short-circuited end) is formed between the dielectric layers 1a and 1b and between 1c and 1d. The conductor films having the ground potential are connected to each other by via-hole conductors. The other end of the microstrip line and the ground potential conductor film are led to the surface of the substrate 1 via via-hole conductors. Here, the strip line, the ground potential conductor film, and the via-hole conductor can be said to be the internal conductor 2 fired integrally with the dielectric layers 1a to 1d, and can also be used as a conductor forming a predetermined wiring network.
[0021]
The outer conductor 3 is a conductor film made of a conductor film containing Ag or Cu as a main component, and is formed on the surface of the base 1 so as to be electrically connected to the above-described via-hole conductor, for example. In this way, in addition to the conductor connected to the internal conductor 2, it can also be used for a conductor to be a terminal electrode and a wiring pattern for forming a predetermined wiring network. The outer conductor 3 is preferably made of the same material as that of the inner conductor 2 and fired integrally with the base body. However, the outer conductor 3 is baked on the base body 1 having the inner conductor 2 by separate firing. It doesn't matter.
[0022]
The above-described dielectric layers 1a to 1d are required to have a high frequency characteristic, for example, a Qf value as a resonator, for example, and are structurally fired integrally with the internal conductor 2 mainly composed of at least Ag or Cu. The firing temperature of the dielectric layers can be fired at, for example, 940 ° C. or lower, which is lower than the melting point of Ag or Cu, and the sintering start temperature (shrinkage start temperature) of the dielectric layers 1a to 1d is adjusted to match the sintering behavior. It is important that the temperature is 830 ° C. or lower.
[0023]
The dielectric layers 1a to 1d are composite oxides containing at least Mg, La, and Ti as metal elements. When the composition formula based on these molar ratios is expressed as xMgO · yLa ₂ O ₃ · zTiO ₃ , It is important to be within the range (including line segments) surrounded by the points ab-c-d-a in the ternary diagram showing the relationship between x, y, and z which are the respective molar ratios of 2 And B, an alkali metal, Si and an alkaline earth metal, and 5 to 30 parts by weight of a grain boundary phase forming component. Here, the points a, b, c, d, and e are the molar ratios of point a (x = 35.5, y = 0.5, z = 64.0), point b (x = 16.0, y = 16.0, z = 68.0). ), Point c (x = 1.0, y = 20.0, z = 79.0), point d (x = 0.5, y = 14.5, z = 85.0), point e (x = 27.5, y = 0.5, z = 72.0) Yes.
[0024]
This is because the main crystal phase is formed from at least one of La ₄ Ti ₉ O ₂₄ , MgTi ₂ O ₅ and La _0.66 TiO _{2.99 3} after firing.
[0025]
Thus, a good Qf value can be obtained in a polygonal region (including a line segment) surrounded by the points ab-c-d-a in the ternary diagram of FIG.
[0026]
Further, an area fg-h-ijkf included in this area, a point f (x = 34.0, y = 1.0, z = 65.0), a point g (x = 28.7, y = 5.3, z = 65.9), point h (x = 23.4, y = 7.9, z = 68.7), point i (x = 17.2, y = 10.3, z = 72.5), point j (x = 12.2, y = 11.5, z = 76.3), in the composition within the point k (x = 29.7, y = 2.0, z = 68.3), the temperature coefficient τf of the resonance frequency is within ± 50 ppm / ° C. In a high-frequency component such as the resonator shown in FIG. This is preferable because the characteristics are very stable with respect to temperature.
[0027]
The grain boundary phase forming component containing B, alkali metal, Si and alkaline earth metal was used, and by using these components, the firing temperature could be 940 ° C. or lower and the firing shrinkage start temperature This is because the Qf value can be 15000 [GHz] or more.
[0028]
The amount of the grain boundary phase forming component is 5 to 30 parts by weight with respect to 100 parts by weight of the low-loss ceramic filler. When the amount is less than 5 parts by weight, the effect of lowering the firing temperature is small. When the conductor as the main component cannot be fired simultaneously, on the contrary, when it exceeds 30 parts by weight, the Qf value decreases. For the above reasons, the grain boundary phase forming component amount is desirably 10 to 20 parts by weight with respect to 100 parts by weight of the main component.
[0029]
When a grain boundary phase-forming _{components, lB 2 O 3 · mA 2} O · nSiO 2 · oRO the formula by weight ratio (A is at least one alkali metal, R represents at least one alkaline earth metal) expressed as , l, m, n and o are, it is important to satisfy the 40 ≦ l ≦ 90,8 ≦ m ≦ 20,1 ≦ n ≦ 20,1 ≦ o ≦ 20, l + m + n + o = 100.
[0030]
Here, the amount of B ₂ O ₃ is set to 40 ≦ l ≦ 90 because when l is less than 40% by weight, the effect of lowering the firing temperature is small, and the main component is Ag or Cu having a melting point of around 1000 ° C. Simultaneous firing with the conductor becomes difficult. Conversely, when it exceeds 90% by weight, the ratio of the glass phase in the sintered body increases and the Qf value decreases. Therefore, 50 ≦ l ≦ 70 wt% is desirable from the viewpoint of maintaining sinterability and obtaining a high Qf value.
[0031]
Also, the reason the 8 ≦ m ≦ 20% by weight of A ₂ O amount m, if m is less than 8% by weight, the effect of lowering the firing temperature is low, a conductor mainly composed of Ag or Cu Simultaneous firing becomes difficult. Conversely, if it exceeds 20% by weight, the crystal phase changes and the Qf value decreases. From the viewpoint of the Qf value of the dielectric ceramic, 12 ≦ m ≦ 20% by weight is desirable. Here, A is at least one of alkali metals, and examples of the alkali metal include Li, Na, and K. Li is particularly desirable.
[0032]
Furthermore, the SiO ₂ amount n is set to 1 ≦ n ≦ 20% by weight because when n is less than 1% by weight, the shrinkage start temperature in the sintering process of the dielectric ceramic becomes higher than 830 ° C. It becomes difficult to approximate the sintering behavior, and the substrate is likely to warp. On the other hand, if it exceeds 20% by weight, the Qf value of the dielectric ceramic decreases. From the viewpoint of the Qf value of the dielectric ceramic, c is preferably 5 ≦ n ≦ 15% by weight.
[0033]
Furthermore, the RO amount o is set to 1 ≦ o ≦ 20% by weight because when o is less than 1% by weight, the shrinkage start temperature in the sintering process of the dielectric ceramic becomes higher than 830 ° C. It becomes difficult to approximate the sintering behavior, and the substrate is likely to warp. On the other hand, if it exceeds 20% by weight, the Qf value of the dielectric ceramic decreases. In particular, from the viewpoint of the sinterability of the dielectric ceramic and the Qf value, d is preferably 5 ≦ o ≦ 15% by weight. Here, R is at least one of the alkaline earth metals, and examples of the alkaline earth metal include Be, Mg, Ca, Sr, Ba, and the like. Of these, Ba is preferable from the viewpoint of the Qf value.
[0034]
The high frequency dielectric ceramic composition of the present invention is obtained by weighing a predetermined amount of MgCO ₃ powder, La ₂ O ₃ powder, TiO ₂ powder as raw material powder, and mixing and pulverizing the raw material powder with balls such as ZrO _2. The mixture is dried, and the dried product is calcined at 950 to 1200 ° C. for 1 to 4 hours in an oxidizing atmosphere such as the air.
[0035]
To the obtained calcined powder, for example, a predetermined amount of B ₂ O ₃ powder, Li ₂ CO ₃ powder, SiO ₂ powder, and alkaline earth metal-containing compound (carbonate, hydroxide, etc.) powder is weighed and added. _After mixing and pulverizing with _two balls, this mixed powder was calcined at 650 to 850 ° C., and then again pulverized and dried with a ZrO ₂ ball until the pulverized particle size became 2.5 μm or less. Formed into a predetermined shape by a known method such as a doctor blade method or the like, and baked at 940 ° C. or less, particularly at 870 to 920 ° C. for 0.5 to 2 hours in a non-oxidizing atmosphere such as air, oxygen atmosphere or nitrogen atmosphere Can be obtained. The raw material powder may be a metal salt such as a hydroxide, carbonate, nitrate, etc. that generates an oxide upon firing.
[0036]
The alkaline earth metal is preferably added as a glass frit containing B, Li, and Si from the viewpoint of improving the sinterability. In this case, the amounts of B, Li, and Si are the total amount of the amount contained in the glass frit and the amount added as a powder.
[0037]
In the dielectric ceramic thus obtained, crystals containing at least one of the five crystal phases of TiO ₂ , La ₄ Ti ₉ O ₂₄ , MgTi ₂ O ₅ , La _0.66 TiO _2.993 , and La ₂ Ti ₂ O ₇ are formed. However, among these crystal phases, La ₄ Ti ₉ O ₂₄ , MgTi ₂ O ₅ or La _0.66 TiO _2.993 is preferably present as the main crystal phase.
[0038]
In the dielectric ceramic for high frequency of the present invention, MnO ₂ may be added and contained in the production process such as the mixing and pulverizing process of the raw material, or Al, Fe, Hf, Sn etc. may be included.
[0039]
【Example】
Example 1
First, each raw material powder of MgCO ₃ , La ₂ O ₃ and TiO ₂ with a purity of 99% or more is weighed in the ratio shown in Table 1, and pure water is added to the raw material powder as a medium to a ball mill using ZrO ₂ balls. After pulverizing and mixing for 20 hours, the mixture was dried, and the dried product was calcined in the atmosphere at a temperature of 1150 ° C. for 3 hours.
[0040]
Using carbonate powder as obtained calcined product with a purity of 99% or more of _{B 2 O 3, Li 2 CO} 3, Na 2 CO 3, K 2 CO 3, SiO 2 powder, further containing an alkaline earth metal compound, Table It was weighed so that the ratio shown in 1, pure water as a medium, ball using ZrO ₂ balls - and mixed 20 hours wet in mill. The mixture was then dried and calcined at 800 ° C. for 1 hour. This calcined product is pulverized so that the pulverized particle size is 1.0 μm or less, and is press-molded at a pressure of 1 ton / cm ² into a cylindrical shape having a diameter of about 10 mm and a height of about 8 mm as a sample for dielectric property evaluation. Were fired at the temperature shown in Table 1 for 2 hours to obtain a cylindrical sample having a diameter of about 8 mm and a height of about 6 mm. At this time, the shrinkage start temperature was measured by measuring heat shrinkage.
[0041]
The dielectric properties were evaluated by measuring the relative dielectric constant and the Q value at a frequency of 4 to 10 GHz using a dielectric cylindrical resonator method after surface grinding of both end faces of the cylindrical sample. Table 1 shows the Qf value represented by the product of the Q value and the measurement frequency f.
[0042]
The temperature coefficient τf of the resonance frequency is calculated by calculating the temperature coefficient τf of the resonance frequency at −40 ° C. and + 85 ° C. with reference to the resonance frequency at 25 ° C. As a result, the temperature coefficient τf of the resonance frequency of all the samples is ± It was within the range of 170 [ppm / ° C.].
[0043]
In FIG. 2, in the composition range surrounded by the point f-g-h-i-j-k-f, excellent characteristics with a temperature coefficient τf of the resonance frequency within ± 50 ppm / ° C. were obtained.
[0044]
[Table 1]

[0045]
From Table 1, the dielectric ceramic according to the present invention has excellent dielectric properties of a dielectric constant of 19 to 52 and a Qf value of 20000 [GHz] or higher, and sintering shrinkage starts at 770 to 830 ° C. It turns out that it has the outstanding sinterability which can be baked at 920 degrees C or less.
[0047]
As the alkali metal, K was used for sample number 8, Na was used for sample number 10, and Li was used for the others. Moreover, as alkaline earth metal, Ba was used for sample number 40, Sr was used for sample number 41, and Ba and Ca were used for others. At this time, the weight ratio of BaO and CaO was 1: 1. In particular, from the comparison of sample number 40 (Ba) and sample numbers 18 and 41 (Sr), when only Ba is used as the alkaline earth metal, a very good value can be obtained with a Qf value of 30000 [GHz]. .
[0048]
In the sample outside the polygonal line segment ab in FIG. 2 (sample numbers 21 and 22) or the sample outside the line segment cd (sample number 23), La is a crystal phase having a low Q value. ₂ Ti ₂ O ₇ is formed, and as a result, the Qf value is greatly reduced to 2500, 5000, 5000 [GHz] .
[0049]
Further, the sample outside the polygonal line segment de in FIG. 2 (sample numbers 25 and 26) or the sample outside the line segment ea (sample number 27) reacts with the grain boundary forming component. As a result, the shrinkage start temperature and sintering temperature increase, and the Qf value does not reach a practical level.
[0050]
Further, in FIG. 2, in the region surrounded by polygons f, g, h, i, j, k, f (sample numbers 12, 13, 14, 15, 16, 17, 18, 19, 20), the relative dielectric It has excellent dielectric properties such as a rate of 20 to 30 and a Qf value of 25000 [GHz] or higher, and sintering shrinkage starts at 770 to 800 ° C., and has excellent sinterability capable of firing at 900 ° C. or lower. A dielectric ceramic for high frequency can be obtained.
[0051]
The substrate 1 is formed using a dielectric layer made of the above-mentioned high frequency dielectric ceramic composition, and a high frequency operation such as a microstrip line or a capacitive electrode is made of a conductive material having excellent conductivity such as Ag or Cu inside the substrate 1. Can be formed.
[0052]
Moreover, the inner conductor 2 and the dielectric layers 1a to 1d can be simultaneously fired at a firing temperature ( 920 ° C. or less) that does not reach the melting point of Ag or Cu, and the shrinkage start temperature of the porcelain is also the same as that of the inner conductor 2. Since it can be approximated to the start of the sintering reaction of the conductor material, a laminated component in which no warp is generated in the substrate 1 can be obtained.
[0053]
The external conductor 3 can also be fired at the same time as the substrate 1.
[0054]
【The invention's effect】
According to the dielectric ceramic composition for high frequency of the present invention, since it has a Qf value of 20000 [GHz] or higher in the high frequency region, it is possible to realize high-frequency components and substrates with small size and high performance, and a firing temperature of 920 ° C. or lower. It becomes possible to make shrinkage start temperature 830 degrees C or less.
[0055]
For this reason, it can be fired at the same time as a conductor material such as Ag or Cu, and in this case, it becomes a laminated part in which warpage and distortion of the substrate caused by mismatch of the shrinkage behavior of the conductor metal are suppressed.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an example of a laminated component according to the present invention, for example, a resonator.
FIG. 2 is a ternary diagram showing the relationship between x, y and z molar ratios of the high frequency dielectric ceramic composition of the present invention.

Claims (3)

A composite oxide containing at least Mg, La, and Ti as metal elements, and when the composition formula by these molar ratios is expressed as xMgO · yLa ₂ O ₃ · zTiO ₂ , in the original figure, with in the range of polygon surrounded by the following points a-b-c-d- e-a ( including a line _{segment), La 4 Ti 9 O 24} , MgTi 2 O 5 and _{La 0. When} a composition formula by weight ratio of a main component having at least one of ₆₆ TiO _2.993 as a main crystal phase and a weight ratio is expressed as lB ₂ O ₃ · mA ₂ O · nSiO ₂ · oRO, the above-mentioned l, m, n, And o
40 ≦ l ≦ 90
8 ≦ m ≦ 20
1 ≦ n ≦ 20
1 ≦ o ≦ 20
l + m + n + o = 100
A: At least one of alkali metals
R: At least one of alkaline earth metals
Consists of a grain boundary phase-forming component is the major component relative to 100 parts by weight, high frequency dielectric ceramic composition wherein the grain boundary phase-forming component, characterized in that 5 to 30 parts by weight.
Point a (x = 35.5, y = 0.5, z = 64.0)
Point b (x = 16.0, y = 16.0, z = 68.0)
Point c (x = 1.0, y = 20.0, z = 79.0)
Point d (x = 0.5, y = 14.5, z = 85.0)
Point e (x = 27.5, y = 0.5, z = 72.0)
x + y + z = 100 Claim 1 high frequency dielectric ceramic composition according to R of the grain boundary phase-forming component characterized in that it is a Ba. Inside and surface of a substrate comprising a dielectric layer stacked, a laminated component having a conductor whose main component is Ag and / or Cu, for high frequency according the dielectric layer to claim 1 or 2 A laminated part comprising a dielectric ceramic composition.

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