JPH11209174A - Porcelain composition for high frequency and production of porcelain for high frequency - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a colored porcelain for high frequency having a small dielectric loss in a high frequency region of >=30 GHz and a relative dielectric constant regulable in the range of 5-80 by firing at 800-1,000 deg.C. SOLUTION: A compsn. prepd. by adding 0.04-20 wt.% B2 o3 and 0.01-10 wt.% CuO or 0.05-30 wt.% glass contg. SiO2 and B2 O3 , and 0.05-10 wt.% CuO to a multiple oxide whose entire compsn. by atomic ratio is represented by n(Zn1-x Mgx ).(Ti1-y Siy ) (where 0<xh0.75, 0<y<1.0 and 0.14<=n<=3.5) as a principal component is compacted and fired at 800-1,000 deg.C to obtain the objective brownish-colored porcelain contg. a willemite type crystal phase 2 and at least one among an i-menite type crystal phase 1, a spinel type crystal, phase, a TiO2 crystal phase and an Sin. crystal phase and having such high-frequency characteristics as a dielectric constant of 5-80 and <=20×10<-4> dielectric loss at 30-60 GHz.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a high-frequency porcelain composition and a method for producing a high-frequency porcelain.
In particular, it can be co-fired with copper and silver, and can be used for wiring boards, dielectric resonators, LC filters, capacitors, dielectric waveguides and dielectric antennas used at high frequencies such as microwaves and millimeter waves. The present invention relates to a high frequency porcelain composition and a method for manufacturing the high frequency porcelain.

[0002]

2. Description of the Related Art In recent years, with the era of advanced information technology, information transmission tends to be faster and higher in frequency. New media (wireless LAN, automobile anti-collision radar) such as mobile radio such as car phone and personal radio, satellite broadcasting, satellite communication, CATV, etc., are being driven to higher frequencies. It is strongly desired that the microwave circuit element has a higher frequency.

In such a microwave circuit element, it is desired to use a low-resistance metal such as copper or silver as a conductor for forming a circuit in consideration of not only the dielectric loss of the dielectric but also the loss of the conductor. ing.

Therefore, in order to satisfy the above-mentioned requirement for low loss and the like, for example, as disclosed in JP-A-5-225825, a circuit board or the like made of a composite perovskite type compound-based dielectric ceramic composition is disclosed. Has been proposed.

[0005]

However, in the case of a perovskite type compound material as disclosed in JP-A-5-225825 or a conventional circuit board using alumina as an insulating substrate, the firing temperature is 1300 to 1600.
Since the temperature is as high as ° C., there has been a problem that multilayering and fine wiring using copper, silver or the like as a wiring conductor cannot be performed.

Conventional glass ceramic materials include copper,
Simultaneous firing with a low-resistance metal such as silver is possible, and multi-layering is possible, but most of them have a dielectric loss of 10 GHz.
In the microwave region of z, it is as large as 20 × 10 ⁻⁴ or more, and satisfactory characteristics have not been obtained in terms of reducing the dielectric loss of high-frequency equipment. Further, conventional glass ceramics can be fired at 1000 ° C. or lower, but are required to be blended with at least 30% by weight of glass to enable such low-temperature firing. As a result, the properties of the porcelain greatly depend on the properties of the glass, so that there is a problem that the excellent properties of the filler component cannot be exhibited.

Further, in the case of dielectric porcelain, the appearance of a product may be poor due to the occurrence of color unevenness or the like, and the yield may be reduced. Therefore, porcelain has been conventionally colored by adding various coloring agents, but in this case, there is a problem that the coloring agent deteriorates the dielectric characteristics of the porcelain, so that the A technical problem is how to color without deteriorating the characteristics.

Accordingly, the present invention is capable of firing at 800 to 1000 ° C., and in particular, has a relative dielectric constant adjustable from 5 to 80 in a high frequency range of 30 GHz or more, and a high frequency which has a low dielectric loss and can be colored. A porcelain composition for
An object of the present invention is to provide a method for producing colored high-frequency porcelain.

[0009]

Means for Solving the Problems As a result of diligent studies on the above problems, the present inventor has found that a composite oxide containing Zn, Mg, Ti and Si in a specific composition has a C content as a sintering aid.
uO and B ₂ O ₃ , or CuO and at least SiO ₂ ,
By adding the glass containing B ₂ O ₃ at a specific ratio, a liquid phase reaction mainly composed of Zn generated from the composite oxide and a liquid phase reaction by a B (boron) component occur, and the amount of 800 Can be fired at a temperature of up to 1000 ° C., and by firing, as a crystal phase, a willemite type crystal phase containing at least Zn, Mg and Si, an ilmenite type crystal phase containing Mg, Zn and Ti, and a spinel type crystal phase containing Zn and Ti By precipitating the crystal phase, 5-80
The present inventors have found that it is possible to obtain a porcelain colored in a tea system having a relative permittivity and a low dielectric loss which can be adjusted by the method described above, and have led to the present invention.

That is, the high frequency ceramic composition of the present invention contains at least Zn, Mg, Ti and Si, and has a composition according to the atomic ratio of the metal of n (Zn _1-x Mg _x ) · (Ti _1-y Si _y ), 0 <x ≦ 0.75, 0 <y <1.0, 0.
70 to 99.95% by weight of a main component composed of a composite oxide satisfying 14 ≦ n ≦ 3.5, 0.04 to 20% by weight of B ₂ O _3, and 0.01 to 10% by weight of CuO. Features.

Another high frequency porcelain composition of the present invention contains at least Zn, Mg, Ti and Si, and has a composition according to the atomic ratio of the metal of n (Zn _1-x Mg _x ) · (Ti _{1- y} Si _y ), 0 <x ≦ 0.75, 0 <y <1.0, 0.
60 to 99.9% by weight of a main component composed of a composite oxide satisfying 14 ≦ n ≦ 3.5, and at least SiO ₂ , B ₂ O
0.05 to 30% by weight of glass containing ₃
5 to 10% by weight.

The above composition is characterized in that it contains a willemite type crystal phase containing at least Zn, Mg and Si.
ilmenite type crystal phase containing n, Mg and Ti, spinel type crystal phase containing at least Zn and Ti, TiO
It is characterized by containing at least one of _two crystal phases and SiO ₂ crystal phase.

In terms of characteristics, the dielectric constant (εr) at 30 to 60 GHz can be adjusted within a range of 5 to 80, and the dielectric loss is 20 × 10 ⁻⁴ or less.

The method for producing a high-frequency porcelain according to the present invention comprises the steps of:
It is characterized by firing at 0 ° C.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The high frequency porcelain composition of the present invention comprises:
As a first embodiment, a main component of a composite oxide containing at least Zn, Mg, Ti and Si is 70 to 99.95.
% By weight, and B ₂ O ₃ 0.04-20 wt% as a sintering aid, is made of a CuO0.01~10 wt%. When the composition of the main component is represented by n (Zn _1-x Mg _x ) · (Ti _1-y Si _y ) according to the atomic ratio of the metal constituting the composite oxide, 0 <x ≦ 0.75 , 0 <y <1.0, 0.
It is composed of a composite oxide satisfying 14 ≦ n ≦ 3.5.

According to the above-mentioned main component composition, by substituting a part of Zn with Mg, it has an effect of stably depositing an ilmenite type crystal phase and reducing dielectric loss. However, when the substitution amount x exceeds 0.75, the absolute amount of Zn becomes insufficient, it becomes difficult to form a liquid phase with the B component in the sintering aid, and a large amount of the sintering aid is not added. However, the porcelain cannot be densified, and accordingly, the dielectric properties are greatly deteriorated. Substitution amount x of Mg for Zn
Is preferably 0.1 ≦ x ≦ 0.4.

In the above main component composition, (Ti + S
The ratio n value of (Zn + Mg) to i) is 0.14 ≦ n
The reason for ≦ 3.5 is that if n is smaller than 0.14, Zn
If the O phase becomes excessive and the dielectric properties deteriorate, and if n exceeds 3.5, the TiO ₂ phase becomes excessive and the sinterability deteriorates, and sintering cannot be performed unless a large amount of sintering aid is added. This is because the dielectric characteristics deteriorate. n is particularly 0.5 ≦ n ≦
1.5 is desirable.

Further, in the above-mentioned main component composition, the dielectric constant can be increased by changing the amounts of Ti and Si and increasing the amount of Ti, and the dielectric constant can be decreased by increasing the amount of Si. By changing y in the range of 0 <y <1.0, the dielectric constant can be arbitrarily controlled in the range of 5 to 80.

Further, as a sintering aid, the amount of B ₂ O ₃ and C
The reason for limiting the uO amount to the above ratio is that CuO and B ₂ O ₃
Is less than 0.05% by weight, in other words, when the amount of the main component composed of a composite oxide containing at least Zn, Mg, Ti, and Si is more than 99.95% by weight, 8
The composition cannot be sufficiently densified at a low temperature of 00 to 1000 ° C., and in the characteristics of a substrate manufactured using this composition,
This is because the porcelain is not densified, so that the dielectric constant decreases and the dielectric loss increases.

On the other hand, if the total amount of CuO and B ₂ O ₃ is more than 30% by weight, in other words, if the amount of the main component is less than 70% by weight, the liquid phase flows away at a low temperature of 700 ° C. or less, and the shape of the porcelain is reduced. This is because the product shape cannot be maintained, and the dielectric loss in the high frequency region of 30 to 60 GHz becomes as high as 20 × 10 ⁻⁴ or more from the viewpoint of porcelain characteristics. A preferred composition range of the main component and CuO and B ₂ O ₃ consisting of the above composite oxide, the main component is 85 to 99 wt%, B ₂ O ₃ is 0.5 to 10 wt%, CuO is 0. 5 to 5% by weight.

B ₂ O ₃ is an indispensable component as a sintering aid. If B ₂ O ₃ is less than 0.04% by weight, it is difficult to densify even if the amount of CuO is increased.
Conversely, if it exceeds 20% by weight, the dielectric properties will be degraded.

CuO is a component capable of enhancing sinterability similarly to B ₂ O _3, and is a component which can be colored into a brown system without deteriorating the dielectric properties.
If the content is less than 5% by weight, a sufficient coloring effect cannot be obtained, and
Exceeding the percentage by weight increases the dielectric loss and degrades the characteristics.

The second embodiment of the high-frequency ceramic composition of the present invention includes a main component 60 composed of the above-described composite oxide containing at least Zn, Mg, Ti and Si.
-99.9% by weight and at least SiO 2 as a sintering aid.
Glass 0.05 to 30 wt% containing ₂ and B ₂ O _3, is made of a CuO0.05~10 wt%.

The reason why the amount of the glass is limited to the above ratio is that the total amount of the above glass and CuO is 0.1% by weight.
Less or, in other words, at least Zn and Mg,
The main component amount of the composite oxide containing Ti and Si is 9
If the content is more than 9.9% by weight, the composition cannot be sufficiently densified at a low temperature of 800 to 1000 ° C., and in the characteristics of a substrate produced using this composition, the dielectric constant decreases because the porcelain is not densified. This is because the dielectric loss increases.

The total amount of CuO and B ₂ O ₃ is 4
0% by weight, in other words, the amount of the main component is 60% by weight.
If less than the weight%, 600 ° C. and a low temperature liquid phase of erosion following not be maintained the product shape impair the shape of the porcelain, also dielectric loss 20 × 10 in a high frequency region of 30~60GHz terms porcelain characteristic ^-4 This is because it is higher than the above. A preferred composition range of the main component and the glass comprising the above composite oxide, the main component is 80 to 99 wt%, B ₂ O ₃ is 0.5 to 15 wt%, in CuO0.5~5 wt% is there.

The above glass is an indispensable component as a sintering aid. If the amount of glass is less than 0.05% by weight, it is difficult to densify even if the amount of CuO is increased. If the content exceeds% by weight, the dielectric properties deteriorate.

CuO is a component that enhances the sinterability similarly to the above glass, and is a component that can be colored into a brown system without deteriorating the dielectric properties.
If it is less than 05% by weight, a sufficient coloring effect cannot be obtained, and
If it exceeds 0% by weight, the dielectric loss increases, and the characteristics deteriorate.

The high frequency porcelain composition of the present invention can be used in any of the first and second embodiments in an oxidizing atmosphere such as air or a non-oxidizing atmosphere such as nitrogen or argon. By baking in a temperature range of 1000 ° C., it is possible to densify to a relative density of 95% or more.

The high frequency porcelain produced in this manner contains a willemite-type crystal phase containing at least Zn, Mg and Si, and further contains an ilmenite-type crystal phase containing at least Zn, Mg and Ti.
And at least one of a spinel crystal phase containing Ti and Ti, a TiO ₂ crystal phase and a SiO ₂ crystal phase.

For example, it has a tissue structure as shown in FIG. 1, FIG. 2 and FIG. FIG. 1 shows that at least Zn, M
It is composed of an ilmenite type crystal phase 1 containing g and Ti, a willemite type crystal phase 2 containing at least Zn, Mg and Si, and an amorphous grain boundary phase 3.

FIG. 2 shows that at least Zn, Mg and Ti
Ilmenite type crystal phase 1 containing at least Zn, M
It comprises a willemite-type crystal phase 2 containing g and Si, a spinel-type crystal phase 4 containing at least Zn and Ti, and an amorphous grain boundary phase 3.

FIG. 3 shows that at least Zn, Mg and Ti
Ilmenite type crystal phase 1 containing at least Zn, M
a willemite type crystal phase 2 containing g and Si, a spinel type crystal phase 4 containing at least Zn and Ti,
It is composed of an O ₂ crystal phase 5, an SiO ₂ crystal phase 6, and an amorphous grain boundary phase 3.

The ilmenite type crystal has a crystal structure belonging to a trigonal lattice represented by FeTiO _{3. In} the porcelain of the present invention, it is presumed that Fe is replaced by Zn. The willemite-type crystal phase is Zn ₂ SiO ₄
It is estimated to be.

As described above, according to the present invention, in a porcelain, a willemite type crystal phase containing at least Zn, Mg and Si, and further, an ilmenite type crystal phase containing at least Zn, Mg and Ti, at least Zn and Ti, Containing spinel type crystal phase, TiO ₂ crystal phase and SiO ₂
By depositing at least one of the crystal phases, the relative dielectric constant can be adjusted between 5 and 80, and a low dielectric loss can be obtained.

In the case of the first embodiment using B ₂ O ₃ as a sintering aid, the amorphous grain boundary phase 3 contains Zn and B
In the case of the second embodiment using glass containing SiO ₂ and B ₂ O ₃ as a sintering aid, the second embodiment is made of a material containing Si, Zn and B.

Although the location of CuO contained in the porcelain contained as a porcelain component in the present invention is not clear, it is either dissolved in the spinel-type crystal phase or a metal or It is presumed that they exist as oxides.

As the glass containing SiO ₂ and B ₂ O ₃ used in the second embodiment of the present invention, borosilicate glass, zinc borosilicate glass, lead borosilicate glass and the like are generally mentioned. the SiO ₂ 5~80
%, B ₂ O ₃ at a ratio of ₄ to 50% by weight, and other components containing Al ₂ O ₃ at a ratio of 30% by weight or less and an alkali metal oxide at a ratio of 20% by weight or less are preferably used. A mixture of these oxide components in a predetermined ratio is melted, cooled, and vitrified.

The method of manufacturing the high-frequency porcelain of the present invention is as follows: ZnO, TiO ₂ , MgO,
Each oxide powder of SiO ₂ or a composite compound of two or more thereof (for example, ZnTiO ₃ , Zn ₂ TiO ₄ ,
MgTiO ₃ , Mg ₂ TiO ₄ , MgSiO ₃ , Mg ₂
SiO ₄ , ZnSiO ₃ , Zn ₂ SiO ₄ , (Zn, C
u) ₂ TiO ₄ ), etc., and further, in addition to oxides, carbonates, acetates, nitrates, etc. which can form oxides during the sintering process. The main component raw materials are weighed and mixed so that the atomic ratio of the metals satisfies the above main component composition.

According to the first embodiment of the present invention, B ₂ O ₃ powder or B ₂ S ₃ , H capable of forming an oxide during the sintering process is used as a sintering aid for the above main component materials. ₂ B
O ₃ , BN, B ₄ C, etc., as B ₂ O ₃ ,
From 0 to 99.95% by weight, B ₂ O ₃ from 0.04 to 20 wt%, is added and mixed so CuO0.01~10 wt%, and.

Further, according to the second embodiment of the present invention, a glass powder containing SiO ₂ and B ₂ O ₃ as a sintering aid as described above is added to the above-mentioned main component material. 60 to 99.9 wt%, 0.1 to 30 wt% glass containing SiO _2, B ₂ O _3, is added and mixed so that CuO0.05~10 wt%.

The raw material powder is preferably a fine powder having an average particle diameter of 2.0 μm or less, particularly 1.0 μm or less, in order to enhance dispersibility and obtain stable dielectric constant and low dielectric loss. .

Next, after appropriately adding a binder to the mixed powder added and mixed at the above ratio, any desired powder is obtained by, for example, a die press, a cold isostatic press, an extrusion molding, a doctor blade method, a rolling method, or the like. After molding into shape, N ₂ , A
800 to 1000 ° C., particularly 900 to 1000 ° C. in a non-oxidizing atmosphere such as r or in an oxidizing atmosphere such as air.
Baking at a temperature of 0.1 to 5 hours to obtain a relative density of 9
It can be densified to 5% or more. If the firing temperature at this time is lower than 800 ° C., the porcelain will not be sufficiently densified, and
If the temperature exceeds 00 ° C., densification is possible, but simultaneous firing with conductors such as copper and silver cannot be performed. Incidentally, at the time of simultaneous firing, it is necessary to fire in a non-oxidizing atmosphere when copper is used as the conductor and in a non-oxidizing or oxidizing atmosphere when using silver as the conductor.

According to the method of the present invention, Zn, Mg,
Composite oxide composed of Ti and Si, CuO and B
By combining ₂ O ₃ or a glass containing CuO, SiO ₂ , and B ₂ O ₃ , a more active liquid phase reaction of a liquid phase mainly composed of Zn and a B (boron) component generated from the composite oxide occurs. As a result, the porcelain can be densified with a small amount of the sintering aid. Therefore, the amount of the amorphous phase at the grain boundary, which causes an increase in dielectric loss, can be minimized. Therefore, a lower dielectric loss can be obtained in a high frequency region.

Further, the porcelain composition according to the present invention comprises:
Since it can be fired at 0 to 1000 ° C., especially gold,
It can be used as an insulating substrate of a wiring board for wiring silver, copper, or the like. In the case of manufacturing a wiring board using such a porcelain composition, for example, according to a known tape forming method, for example, a doctor blade method, a rolling method, or the like, the mixed powder prepared as described above is used to form an insulating layer forming green. After making the sheet, on the surface of the sheet for the wiring circuit layer,
At least one metal of gold, silver and copper, in particular,
Using a conductive paste containing copper powder, print the wiring pattern on the surface of the green sheet in a circuit pattern by screen printing, gravure printing, etc. In some cases, fill the above conductive paste after forming through holes and via holes in the sheet I do. After that, a plurality of green sheets are stacked and pressed, and then fired under the above-described conditions, whereby the wiring layer and the insulating layer can be fired simultaneously.

[0045]

EXAMPLES Example 1 B ₂ O _{3 having} an average particle size of 1 μm or less, Cu having an average particle size of 1 μm or less
O, Zn ₂ TiO ₄ , MgTi having an average particle size of 1 μm or less
_{O 3, Zn 2 SiO 4,} TiO 2, SiO 2 and Tables 1 and 2
Was mixed according to the composition of Then, an organic binder, a plasticizer, and toluene were added to the mixture, and a green sheet having a thickness of 300 μm was prepared by a doctor blade method.
Then, five green sheets were laminated and thermocompression-bonded at a temperature of 50 ° C. by applying a pressure of 100 kg / cm ² . After debinding the laminate obtained for a part of the composition at 500 to 700 ° C. in a steam-containing / nitrogen atmosphere, the laminate was fired in dry nitrogen under the conditions shown in Tables 1 and 2 to obtain a porcelain for a multilayer substrate. . In addition, for other compositions, the laminate is exposed to air,
After removing the binder at 500 to 700 ° C., it was fired in the air under the conditions shown in Tables 1 and 2 to obtain a porcelain for a multilayer substrate.

The dielectric constant and dielectric loss of the obtained sintered body were evaluated by the following methods. The measurement is 1-5m in shape diameter
A sample having a thickness of m and a thickness of 2 to 3 mm was cut out and subjected to a dielectric cylinder resonator method at 60 GHz using a network analyzer and a synthesized sweeper. In the measurement,
Excitation of the dielectric resonator was performed by an NRD guide (non-radiative dielectric line), and the dielectric constant and the dielectric loss were calculated from the resonance characteristics of the TE021 and TE031 modes, and the results are shown in Tables 1 and 2. Also, the constituent phases of the porcelain were identified from the X-ray diffraction measurement,
The X-ray diffraction charts of Sample Nos. 7 and 21 are shown in FIGS.

As a comparative example, Zn ₂ TiO ₄ , M
Instead of gTiO ₃ and Zn ₂ SiO ₄ , BaTiO ₃ ,
Similarly, a sintered body was prepared using Al ₆ Si ₂ O ₁₃ (mullite) and evaluated (samples Nos. 38 and 39).

[0048]

[Table 1]

[0049]

[Table 2]

As is clear from the results shown in Tables 1 and 2, the ilmenite type crystal phase ((Zn, Mg) Ti
O ₃ ), Willemite-type crystal phase ((Zn, Mg) ₂ Si
O ₄ ) or a spinel type crystal phase (Zn ₂ Ti
The porcelain of the present invention, in which O ₄ ) is mainly deposited, has a dielectric constant of 5 to 80 and can be adjusted, has a dielectric loss at 60 GHz of 20 × 10 ^-4 or less, and has an excellent characteristic value of 800 to 1
It could be sintered at 000 ° C. As a result of analyzing the crystal grain boundary phase of the porcelain of the present invention by an X-ray microanalyzer, Zn, B and Cu elements were detected from the grain boundary phase.

On the other hand, in Sample No. 32 in which the amount of B ₂ O ₃ was less than 0.04% by weight, the firing temperature was set to 1300 ° C.
Unless it is increased, it cannot be densified, and is not suitable for the purpose of the present invention. On the other hand, in Sample No. 28 in which the total amount of CuO and B ₂ O ₃ exceeded 30% by weight, the dielectric loss was increased due to the large amount of liquid phase, and the dielectric characteristics could not be evaluated at 60 GHz.

Further, (Ti + S) with respect to (Zn + Mg)
In sample No. 11 in which the ratio of i) was small (3.5 <n), an excessive ZnO phase was precipitated, thereby increasing the dielectric loss and
Dielectric properties could not be evaluated at GHz. (Zn +
Mg) to (Ti + Si) (n <0.
14) can not be densified porcelain unless Sample No.15 in the amount of B ₂ O ₃ was added in excess of 20 wt%, B ₂ O
_{When 3} was added in excess of 20% by weight, the liquid phase became excessive and the dielectric loss of the porcelain increased.

In sample No. 28 where x> 0.75, Zn
Since the amount is insufficient, B ₂ O ₃ in the B component and the liquid phase becomes difficult to form a dense porcelain to be added exceeds 30% by weight of the total amount of CuO and B ₂ O ₃ And the dielectric properties deteriorated.

As comparative examples, BaTiO ₃ and Al
₆ Si ₂ O ₁₃ sample No.38,39 using (mullite)
In this case, the dielectric loss was so high that measurement was impossible at 60 GHz.

The porcelain containing 0.01% by weight or more of CuO exhibited a brown to dark brown color.

Example 2 Glass powder shown in Table 3 having an average particle size of 1 μm or less, CuO having an average particle size of 1 μm or less, and Zn having an average particle size of 1 μm or less.
₂ TiO ₄ , MgTiO ₃ , Zn ₂ SiO ₄ are shown in Tables 4 and 5
Was mixed according to the composition of Then, a green sheet was produced in the same manner as in Example 1 using this mixture. Then, five green sheets were laminated and thermocompression-bonded at a temperature of 50 ° C. by applying a pressure of 100 kg / cm ² . After debinding the laminate obtained for a part of the composition at 500 to 700 ° C. in a water vapor-containing / nitrogen atmosphere, the laminate was fired in dry nitrogen under the conditions shown in Tables 4 and 5 to obtain a ceramic for a multilayer substrate. . In addition, for other compositions, the laminate was placed in the air at 50
After debinding at 0 to 700 ° C, Tables 4 and 5
Was fired under the conditions described above to obtain a ceramic for a multilayer substrate. The dielectric constant and dielectric loss of the obtained sintered body were evaluated in the same manner as in Example 1, and the results are shown in Tables 4 and 5.

[0057]

[Table 3]

[0058]

[Table 4]

[0059]

[Table 5]

As is clear from the results of Tables 4 and 5, the ilmenite type crystal phase ((Zn, Mg) Ti
O ₃ ), Willemite crystal phase ((Zn, Mg) ₂ SiO
₄ ) Or spinel type crystal phase (Zn ₂ TiO ₄ )
Are mainly deposited, the dielectric constant is 5 to 80, the dielectric loss at 60 GHz shows excellent characteristic value of 20 × 10 ^-4 or less, and can be sintered at 800 to 1000 ° C. Was. The grain boundary phase of the porcelain of the present invention is represented by X
As a result of analysis by a line microanalyzer, Zn, B and Cu elements were detected in the grain boundary phase.

On the other hand, in the sample No. 65 in which the total amount of CuO and glass is less than 0.1% by weight, densification cannot be achieved unless the firing temperature is increased to 1300 ° C. Was unsuitable for On the other hand, in Sample No. 71, in which the total amount of CuO and glass exceeded 40% by weight, the dielectric loss increased due to the large amount of liquid phase, and the dielectric characteristics could not be evaluated at 60 GHz.

Further, (Ti + S) with respect to (Zn + Mg)
In sample No. 75, in which the ratio of i) is small (n> 3.5), an excessive ZnO phase is precipitated, thereby increasing the dielectric loss and increasing the dielectric loss.
Dielectric properties could not be evaluated at GHz. (Zn +
Mg) to (Ti + Si) (n <0.
14) In sample No. 72, the dielectric loss of the porcelain increased, and measurement was not possible.

In the sample No. 71 where x> 0.75, Zn
Since the amount is insufficient, it is difficult to form a liquid phase with the B component in the glass, and the total amount of CuO and the glass becomes 4%.
Unless added in excess of 0% by weight, the porcelain cannot be densified,
The dielectric properties have deteriorated.

Each porcelain containing 0.01% by weight or more of CuO exhibited a brownish to dark brown color.

Example 3 For various porcelain, the diameter was 1 to 30 mm and the thickness was 2 to 15
A cylindrical sample a) of mm was prepared, and the relationship between the permittivity and the frequency of the dielectric loss was measured. The results are shown in FIGS. 6 and 7. 6 and 7, reference numerals 1 and 2 denote the porcelains of Nos. 7 and 14 in the first embodiment, and reference numeral 3 denotes No. 7 in the second embodiment.
41 porcelain, and as comparison, 4, general-purpose products of cordierite glass ceramic (borosilicate glass 75 wt%, Al ₂ O ₃ 25 wt%), 5 generic alumina ceramic (Al ₂ O ₃ 95 wt% , CaO, MgO 5% by weight). For each porcelain, 1GHz, 10GHz, 20G
The dielectric constant and the dielectric loss were measured by the dielectric cylinder resonator method in the high frequency of 30 Hz, 30 GHz and 60 GHz, the microwave, and the millimeter wave region.

As shown in FIGS. 6 and 7, it can be understood that the cordierite-based glass ceramic, which is a general-purpose product, has a dielectric constant as low as 5, and the general-purpose low-purity alumina has a dielectric constant of 9. In contrast, the product of the present invention has a dielectric constant of 17, 73 and 5.
It was a wide value of 5. General-purpose glass ceramics have low dielectric loss in the low-frequency region, but their characteristics deteriorate as the frequency becomes higher.
It will exceed × 10 ^-4 . Also, general-purpose alumina porcelain increased to 40 × 10 ^{−4 at} 60 GHz. On the other hand, in Examples 1, 2 and 3 of the present invention, the dielectric loss was as low as 15 × 10 ⁻⁴ or less even in the high frequency region at 60 GHz.

[0067]

As described in detail above, the high frequency porcelain composition of the present invention can be densified at a temperature of 800 to 1000 ° C., so that it can be fired simultaneously with wiring of gold, silver, copper and the like. Moreover, the porcelain obtained by firing the above composition exhibits a brownish color and shows a low dielectric loss in a high frequency band of 30 GHz or more, so that it is possible to reduce the loss in circuit elements for microwaves and millimeter waves. In addition, the porcelain can be manufactured with a good yield without appearance defects due to color unevenness.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a structure of a high-frequency porcelain of the present invention.

FIG. 2 is a schematic view showing another example of the structure of the high frequency porcelain of the present invention.

FIG. 3 is a schematic view showing still another example of the structure of the high frequency porcelain of the present invention.

FIG. 4 shows a sample of the high frequency porcelain of the present invention (sample No. 1 in Example 1).
It is an X-ray-diffraction chart figure of 7).

FIG. 5 is a diagram showing a high frequency porcelain (sample No. 1 in Example 1) of the present invention.
It is an X-ray-diffraction chart figure of 21).

FIG. 6 is a diagram showing the relationship between the dielectric constant ε and the frequency f ₀ of the porcelain of the present invention and a conventional porcelain.

FIG. 7 shows a dielectric loss tan between a porcelain of the present invention and a conventional porcelain.
FIG. 4 is a diagram illustrating a relationship between δ and a frequency f ₀ .

[Explanation of symbols]

Reference Signs List 1 Ilmenite type crystal phase (I) 2 Willemite type crystal phase (ZS) 3 Grain boundary phase (G) 4 Spinel type crystal phase (SP) 5 TiO ₂ crystal phase (T) 6 SiO ₂ crystal phase (S)

Claims (7)

[Claims] 1. The composition contains at least Zn, Mg, Ti and Si, and when the composition according to the atomic ratio of the metal is expressed as n (Zn _1-x Mg _x ) · (Ti _1-y Si _y ), 0 <x ≦ 0.75, 0 <y <1.0, 0.
70 to 99.95% by weight of a main component composed of a composite oxide satisfying 14 ≦ n ≦ 3.5; 0.04 to 20% by weight of B ₂ O ₃ ; and 0.01 to 10% by weight of CuO. A porcelain composition for high frequencies, characterized by the following. 2. The composition contains at least Zn, Mg, Ti and Si, and when the composition according to the atomic ratio of the metal is represented by n (Zn _1-x Mg _x ) · (Ti _1-y Si _y ), 0 <x ≦ 0.75, 0 <y <1.0, 0.
60 to 99.9% by weight of a main component composed of a composite oxide satisfying 14 ≦ n ≦ 3.5, and at least SiO ₂ , B ₂ O
0.05 to 30% by weight of glass containing ₃
A high frequency porcelain composition comprising 5 to 10% by weight. 3. The high frequency ceramic composition according to claim 1, comprising a willemite-type crystal phase containing at least Zn, Mg and Si. 4. An ilmenite type crystal phase containing at least Zn, Mg and Ti, a spinel type crystal phase containing at least Zn and Ti, at least one of a TiO ₂ crystal phase and a SiO ₂ crystal phase. The high frequency porcelain composition according to claim 3, wherein 5. Dielectric constant (εr) at 30 to 60 GHz is 5
The high frequency ceramic composition according to any one of claims 1 to 4, wherein the dielectric composition has a dielectric loss of 20 to ^10-4 or less. 6. The composition contains at least Zn, Mg, Ti and Si, and when the composition according to the atomic ratio of the metal is represented by n (Zn _1-x Mg _x ) · (Ti _1-y Si _y ), 0 <x ≦ 0.75, 0 <y <1.0, 0.
Composition composed of 70 to 99.95% by weight of a main component composed of a composite oxide satisfying 14 ≦ n ≦ 3.5, 0.04 to 20% by weight of B ₂ O _{3, and} 0.01 to 10% by weight of CuO A method for producing a high-frequency porcelain, wherein the article is formed into a predetermined shape and then fired at 800 to 1000 ° C. 7. The composition contains at least Zn, Mg, Ti and Si, and when the composition according to the atomic ratio of the metal is expressed as n (Zn _{1 -x} Mg _x ) · (Ti _{1 -y} Si _y ), 0 <x ≦ 0.75, 0 <y <1.0, 0.
60 to 99.9% by weight of a main component composed of a composite oxide satisfying 14 ≦ n ≦ 3.5, and at least SiO ₂ , B ₂ O
0.05 to 30% by weight of glass containing ₃
After shaping the composition comprising 5 to 10% by weight into a predetermined shape,
A method for producing a high-frequency porcelain characterized by firing at 800 to 1000C.