JP2002338341A - Porcelain calcined at low temperature, its manufacturing method and wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide porcelain calcined at a low temperature which is dense, has low dielectric constant and high deflective strength and is excellent in sinterability simultaneous with metallization and to provide its manufacturing method and a wiring board. SOLUTION: The porcelain calcined at low temperature is characterized by being constituted of a crystalline phase composed of main crystal of ZnAl2 O4 , α-SiO2 crystal and Zn2 SiO4 crystal and of residual glass phase (MnO2 , B2 O3 or the like) and substantially containing no alkaline metal element and alkaline earth metal element. Further the porcelain calcined at a low temperature has coefficient of water absorption of <=0.1%, coefficient of thermal expansion of >3 ppm/ deg.C and <9 ppm/ deg.C, deflective strength of >=150 MPa, dielectric constant of <=7 and no-load quality coefficient of >=800 in a region of 9 to 13 GHz.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a low-temperature fired porcelain, a method of manufacturing the same, and a wiring board.
Low-temperature fired porcelain that can be fired simultaneously with low-resistance wiring such as g and Cu and has excellent dielectric properties in a high-frequency region, a method of manufacturing the same, and a wiring substrate suitable for matching with GaAs and the like and bonding with metal fittings About.

[0002]

2. Description of the Related Art Conventionally, alumina has been mainly used as an electrically insulating material suitable for a multilayer circuit board or a semiconductor package material. However, faster processing speed,
As the density of wiring has been increased, low-temperature fired materials that can be fired simultaneously with Ag or Cu of low-resistance wiring with low dielectric constant are required. In recent years, miniaturization and low loss of communication-related components in a high-frequency region have been demanded. Low-temperature sintering materials are preferably used as materials satisfying the above requirements. Conventionally, as a low-temperature firing material, a glass-ceramic composite obtained by mixing and firing a glass powder and a ceramic powder has been studied. As a glass powder, a type of a type in which a new crystal is precipitated by a reaction between a glass and a filler and the glass, which crystallizes itself during firing, is used in many cases. As described above, glass containing a large amount of glass (usually about 40 to 70% by mass) and softening of the glass during sintering and precipitation of crystals are easily affected by the manufacturing process of the glass powder. Variation is likely to occur. In other words, there are poor densification due to lowering of the crystallization temperature of the glass due to melting conditions, mixing of impurities, etc., and variations in strength and dielectric properties due to fluctuations in the amount of precipitated crystals. Furthermore, even when grinding glass powder, depending on the conditions,
The glass surface is damaged at the time of pulverization, and the softening and crystallization behaviors of the glass are different, the glass surface reacts to make the glass porous, that is, the specific surface area is increased, and the amount of residual carbon is increased (JP-A-8-73233). No.). Further, in the glass-ceramic composite, when co-firing with Ag or Cu wiring is performed, Ag or Cu diffuses into the glass during the firing process. JP-A-4-321293, JP-A-6-338686, JP-A-7-111372). When the base material and the metallized react and diffuse, the viscosity of the glass at the metallized lower part and the peripheral part is reduced, so that the shrinkage behavior differs from the part without the metallized, and the metallized part is likely to warp or undulate. On the other hand, in order to suppress the reaction between these glasses and metallization, attempts have been made to suppress the warpage by adding an additive such as another glass or oxide to the metallization. The situation is not yet reached.

Further, low-temperature firing materials obtained by adding a small amount of a sintering aid such as a low-melting oxide or glass to ceramics and firing them have been studied, and among them, as disclosed in Japanese Patent Application Laid-Open No. Hei 10-189828. Some have excellent dielectric properties (low dielectric constant, low loss), but these materials
The reality is that the bending strength that satisfies the reliability with respect to the alignment with aAs or the like or the joining with the metal fitting is not obtained.

[0004]

When glass is used as a starting material, in addition to the high cost of glass powder during production (melting and pulverization), as described above, sintering due to the production conditions of glass powder is required. There is a problem of variation in body characteristics,
During co-firing with metallization, the metallized portion is likely to be warped or undulated due to the reaction and diffusion of the metallization into the base material. In addition, when a sintering aid is added to ceramics, the warping and undulation of the metallized portion can be suppressed as compared with the case where glass is used as a starting material, but excellent dielectric properties (low dielectric constant, low dielectric loss) and high resistance are obtained. Both of the bending strengths have not been satisfied. In the present invention, the above problem is solved by reducing the amount of the sintering aid using the calcined powder as a main raw material.
Low-temperature fired porcelain which can be densified at the following temperatures, has low dielectric constant, low dielectric loss, and high bending strength, and is excellent in co-sinterability with metallization, a method for manufacturing the same, and a wiring board The purpose is to get.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention. That is, the low-temperature fired porcelain of the present invention is composed of a main crystal of ZnAl ₂ O ₄ having a high bending strength, a crystal phase composed of α-SiO ₂ crystal and Zn ₂ SiO ₄ crystal, and a remaining glass phase, and an alkali metal element. And substantially no alkaline earth metal element.

The content ratio of the ZnAl ₂ O ₄ crystal and the crystal phase composed of α-SiO ₂ crystal and Zn ₂ SiO ₄ crystal is as follows:
When the total of the crystal phase and the glass phase is 100% by mass,
Preferably it is 45 to 98% by mass, more preferably 6 to 98% by mass.
The content is 5 to 90% by mass, and more preferably 70 to 85% by mass. If the content ratio of the crystal phase is less than 45% by mass, the liquid phase will emerge on the surface of the sintered body after firing. On the other hand, if it exceeds 98% by mass, it does not sinter at 1050 ° C. or less, which is not preferable.

[0007] In the above crystal phase, the content ratio of ZnAl ₂ O ₄ crystal is preferably 30 to 80% by mass, more preferably 45 to 70% by mass, and still more preferably 50 to 65% by mass.
% By mass. The content ratio of α-SiO ₂ crystal is
Preferably it is 0 to 40 mass%, more preferably 0 to 30 mass%, and still more preferably 10 to 20 mass%. Furthermore,
The content ratio of the Zn ₂ SiO ₄ crystal is preferably 0 to 50% by mass, more preferably 10 to 40% by mass, and still more preferably 15 to 35% by mass. By setting the content ratios of the crystal components in the respective preferable ranges, a low-temperature fired porcelain having excellent dielectric properties (low dielectric constant and low dielectric loss) and high bending strength can be obtained.

The above glass phase is not particularly limited.
But SiO_Two, MnO_Two, B_TwoO_Three, Cr _TwoO_Three, TiO_Two,
CoO, NiO and CeO_TwoAnd the like.

The low-temperature fired porcelain of the present invention contains substantially no alkali metal element and no alkaline earth metal element. Here, “substantially not contained” means that an alkali metal element and an alkaline earth metal element are inevitable impurities (about 0.2%).
Mass% or less).
It is not always necessary that the content of the alkali metal element and the alkaline earth metal element be completely 0% by mass. If the content of the alkali metal element and / or the alkaline earth metal element is too large, the dielectric properties (dielectric loss) of the low-temperature fired porcelain obtained are undesirably deteriorated.

In another low-temperature fired porcelain of the present invention, the low-temperature fired porcelain has a crystal phase of 30 to 80% by mass of ZnAl ₂ O ₄ crystal, 0 to 40% by mass of α-SiO ₂ crystal, and Zn ₂ SiO ₄
0-50% by mass of crystals and 0-5% by mass of MnO ₂
And a low-temperature fired porcelain containing 2 to 15% by mass of B ₂ O ₃ , characterized by being substantially free of an alkali metal element and an alkaline earth metal element.

The content ratio of the ZnAl ₂ O ₄ crystal and the crystal phase composed of α-SiO ₂ crystal and Zn ₂ SiO ₄ crystal is as follows:
The total of the crystal phase and the glass phase of MnO ₂ and B ₂ O ₃ is 1
When it is set to 00% by mass, it is preferably 45 to 98% by mass, more preferably 65 to 90% by mass, and still more preferably 70 to 85% by mass. If the content ratio of the crystal phase is less than 45% by mass, the liquid phase will emerge on the surface of the sintered body after firing. On the other hand, if it exceeds 98% by mass, 1050
It is not preferable because it does not sinter at a temperature of below ℃.

The content of ZnAl ₂ O ₄ crystals in the above crystal phase is 30 to 80% by mass, preferably 45 to 70% by mass, more preferably 50 to 65% by mass. The content ratio of the α-SiO ₂ crystal is 0 to 40.
%, Preferably from 0 to 30% by mass, more preferably from 10 to 20% by mass. Further, the content ratio of the Zn ₂ SiO ₄ crystal is 0 to 50% by mass, preferably 10% by mass.
-40 mass%, more preferably 15-35 mass%. Further, the content ratio of MnO ₂ is 0 to 5% by mass,
Preferably 0.1 to 2% by mass, more preferably 0.5 to 2% by mass.
2% by mass. The content ratio of B ₂ O ₃ is 2 to 15% by mass, preferably 5 to 12% by mass, more preferably 7 to 15% by mass.
12% by mass. By containing MnO _{2, a} low-temperature fired porcelain having a high sintering property and a high binder-removing property can be obtained, but if the content exceeds 5% by mass, the dielectric loss decreases. In addition, when B ₂ O ₃ is contained, a dense low-temperature fired porcelain can be obtained.
If it exceeds 5% by mass, the dielectric loss decreases.

[0013] The low-temperature fired porcelain of the present invention is characterized in that after firing, ZnA
The raw material component is not particularly limited as long as it contains at least ZnAl ₂ O ₄ crystal among l ₂ O ₄ crystal, α-SiO ₂ crystal and Zn ₂ SiO ₄ crystal. As a raw material component, an oxide is usually used, and ZnO, SiO ₂ and A
l ₂ O ₃ is preferably used.

The ZnO used as a raw material component is not particularly limited, but high purity ZnO is preferably used. In addition, powder is preferred, but the particle size is not particularly limited,
Usually, those having a size of 0.5 to 3 μm, preferably 0.5 to 1 μm are preferably used. S used as a raw material component
The iO ₂ is not particularly limited, but a high-purity iO ₂ is preferably used. Powder is preferred, but the particle size is not particularly limited, and is usually 0.5 to 5 μm, preferably 0.1 to 5 μm.
Those having a size of 5 to 2 μm are preferably used.

Further, Al ₂ O ₃ used as a raw material component
Is not particularly limited, but those having high purity are preferably used. Powder is preferred, but the particle size is not particularly limited, and is usually 0.2 to 5 μm, preferably 0.5 to 2 μm.
μm is preferably used. In addition, the raw material component does not necessarily need to be an oxide.

The above ZnO, SiO_TwoAnd Al_TwoO_ThreeContaining
The proportions are preferable when the total of these is 100 parts by mass.
Or 20-50 parts by mass of ZnO, SiO_TwoIs 20-6
0 parts by mass, Al_TwoO_ThreeIs 10 to 40 parts by mass, which is more preferable.
Preferably, ZnO is 25 to 45 parts by mass, SiO_TwoIs 25-
50 parts by mass, Al_TwoO_ThreeIs 15 to 40 parts by mass, and
Preferably, 30 to 45 parts by mass of ZnO, SiO_TwoIs 30
~ 45 parts by mass, Al_TwoO _ThreeIs 25 to 35 parts by mass. Up
To make the content ratio of each of the above-mentioned components a preferable range.
Higher dielectric properties (low dielectric constant, low dielectric loss) and higher
A low-temperature fired porcelain having bending strength can be obtained.

[0017] When the MnO ₂ and B ₂ O ₃ as the glass phase is contained in, MnO ₂ and B ₂ O as the raw material powder
Each of the powders ₃ is used, and those having a high purity are preferably used, and those having a particle diameter of usually 0.2 to 5 μm, preferably 0.2 to 3 μm are preferably used.

When MnO ₂ and B ₂ O ₃ are further contained in addition to the above-mentioned ZnO, SiO ₂ and Al ₂ O ₃ , the content ratio thereof is preferably 100 parts by mass, more preferably 20% by mass of ZnO. ５０50 parts by mass, SiO ₂ 20２０60
Parts by weight Al ₂ O ₃ is 10 to 40 parts by weight, MnO ₂ 0 to
5 parts by mass, a B ₂ O ₃ is 2 to 15 parts by weight, and more preferably ZnO 25 to 45 parts by weight, SiO ₂ 25 to 50
Parts by, Al ₂ O ₃ 15 to 40 parts by weight, MnO ₂ 0.
1-2 parts by mass, a B ₂ O ₃ is 5 to 12 parts by weight, more preferably ZnO is 30 to 45 parts by weight, SiO ₂ is 30 to
45 parts by weight, Al ₂ O ₃ is 25 to 35 parts by weight, MnO ₂ is 0.5 to 2 parts by weight, B ₂ O ₃ is 7-12 parts by weight. By setting the content ratio of each of the above components in a preferable range, a low-temperature fired porcelain having excellent dielectric properties (low dielectric constant and low dielectric loss) and high bending strength can be obtained.

Further, in order to form the above glass phase, in addition to MnO ₂ and B ₂ O ₃ , SiO ₂ , Cr ₂ O ₃ , Ti
O ₂ , CoO, NiO, CeO _{2 and the} like can be contained.

In addition to the above-mentioned raw material components, a binder, a plasticizer, a solvent and the like can be used as required. The binder is not particularly limited as long as it can maintain the shape of the molded article. Examples thereof include polyvinyl alcohol, carboxymethylcellulose, ethylcellulose, acetylcellulose, polyvinylether, polyvinylbutyral, etc., and they can be used alone or in combination of two or more. The amount of the binder used is 10
The amount can be preferably 14 to 22 parts by mass, more preferably 17 to 20 parts by mass with respect to 0 parts by mass.

The plasticizer is not particularly restricted but includes, for example, dibutyl phthalate, dioctyl phthalate, glycerin, polyethylene glycol and the like. The use amount of the plasticizer can be preferably 3 to 8 parts by mass, more preferably 4 to 7 parts by mass, based on 100 parts by mass of the raw material components in total. The solvent is not particularly limited as long as it does not adversely affect each component, and examples thereof include aromatic hydrocarbons such as xylene, toluene, and ethylbenzene, ketones such as methyl ethyl ketone and diethyl ketone, ethyl acetate, and isopropyl acetate. And esters such as butyl acetate, alcohols such as ethanol, propanol, isopropanol, butanol, pentanol and hexanol, etc. can be used alone or in combination of two or more.

The low-temperature fired porcelain of the present invention can be obtained by molding and firing using a composition composed of the above-mentioned raw materials and, if necessary, the above-mentioned binder, plasticizer, solvent and the like. .

The water absorption of the low-temperature fired porcelain of the present invention is preferably 0.1% or less, more preferably 0.05% or less, and further preferably 0.03% or less. The lower limit is usually 0%. If the water absorption is too high, the moisture resistance and bending strength decrease, which is not preferable. The coefficient of thermal expansion measured by the method in the following examples is preferably 3 pp.
more than m / ° C and less than 9 ppm / ° C, more preferably 4 to 9 ppm / ° C, and still more preferably 5 to 8 ppm / ° C.
It is. If the coefficient of thermal expansion is out of the above range, Al ₂ O ₃ and Ga
The difference in thermal expansion from As or the like becomes too large, and cracks or the like tend to occur during mounting, which is not preferable.

The bending strength of the low-temperature fired porcelain is 150MP.
a or more, more preferably 170 MPa
As described above, the pressure can be more preferably set to 200 MPa or more. The upper limit is usually 300 MPa. If the bending strength is less than 150 MPa, the substrate is liable to crack at the time of joining with a metal fitting or the like. Further, the dielectric constant can be set to 7 or less, more preferably 6 or less, and further preferably 5.5 or less. The lower limit is usually 5
It is. Furthermore, the no-load quality factor in the 9 to 13 GHz region can be 800 or more, and more preferably 1
000 or more, more preferably 1300 or more.

The method for producing a low-temperature fired porcelain according to the present invention comprises the steps of:
85 to 98% by mass of a calcined powder containing Al ₂ O ₄ crystal and at least one crystal selected from α-SiO ₂ crystal, Zn ₂ SiO ₄ crystal, Al ₂ O ₃ crystal and ZnO crystal, and A raw material component comprising 2 to 15% by mass of B ₂ O ₃ powder is molded, and the molded body is fired at 850 to 1050 ° C.
It is characterized by obtaining a low-temperature fired porcelain having an nAl ₂ O ₄ crystal as a main crystal.

The above calcined powder is essentially composed of ZnAl ₂ O ₄ crystal, α-SiO ₂ crystal, Zn ₂ SiO ₄ crystal, and Al ₂ O ₄ crystal.
_The combination is not particularly limited as long as at least one crystal selected from _three crystals and ZnO crystal is contained. A preferred combination is (ZnAl ₂ O ₄ crystal and α-SiO
₂ crystal and Al ₂ O ₃ crystal), (ZnAl ₂ O ₄ crystal and Al ₂ O
( ₃ crystals) and (ZnAl ₂ O ₄ crystal and Zn ₂ SiO ₄ crystal)
It is. The ZnAl ₂ O ₄ crystal is at least 15% by mass or more (preferably 15 to 60% by mass) in the calcined powder.
More preferably, the content is 20 to 40% by mass. Further, even if the calcined powder is a mixture of each crystal produced from each raw material compound,
Any one may be manufactured at once from all the starting compounds constituting the crystal so as to form a desired combination of crystals.

The calcined powder is usually mixed with a predetermined amount of each raw material compound, and heated at a temperature of 1100 to 1100 in an air atmosphere.
It is obtained by firing at 1200 ° C. for 1 to 5 hours, pulverizing or the like. The preferred particle size is 1 to 3 μm, more preferably 1 to 2 μm. On the other hand, the particle diameter of the B ₂ O ₃ powder is preferably 1 to 5 μm, more preferably 1 to 3 μm.
It is.

The mixing ratio of the calcined powder and the B ₂ O ₃ powder is (85 to 85%) when the total is 100% by mass.
98) / (2 to 15) mass%, preferably (88)
-95) / (5-12)% by mass, more preferably (89)
-93) / (7-11)% by mass. If the amount of the calcined powder is less than 85% by mass or the amount of the B ₂ O ₃ powder exceeds 15% by mass, the liquid phase component will emerge on the surface of the sintered body. On the other hand, if the blending amount of the calcined powder exceeds 98% by mass or the blending amount of the B ₂ O ₃ powder is less than 2% by mass, sintering at 1050 ° C. or less is not preferable.

The raw material components composed of the calcined powder and the B ₂ O ₃ powder are usually formed into a molded article having a predetermined shape by pressure molding, sheet molding (including lamination of a plurality of sheets), and the like. According to the above, molding may be performed after granulation in advance using the binder, plasticizer, solvent and the like exemplified above.

The method of molding the above-mentioned raw material components is not particularly limited, but the molded body is formed by a dry pressure molding method, a doctor blade method, an extrusion method, a roll method, or the like. The molded body is usually fired in an air atmosphere for 0.5 to 3 hours (preferably 1 to 2 hours). Firing temperature is 85
0 to 1050 ° C, preferably 900 to 1000 ° C
It is.

Another method for producing a low-temperature fired porcelain of the present invention is as follows.
ZnAl ₂ O ₄ crystal, α-SiO ₂ crystal, Zn ₂ SiO ₄
Powder containing at least one crystal selected from crystals, Al ₂ O ₃ crystals and ZnO crystals
% By mass and glass component powders 5 to 4 containing Zn and B
0% by mass of a raw material component comprising
It is characterized in that it is fired at 50 to 1050 ° C. to obtain a low-temperature fired porcelain having ZnAl ₂ O ₄ crystal as a main crystal.

The same calcined powder as described for the calcined powder of the invention can be used. Z above
No particular limitation is imposed on the glass component containing n and B, for example, ZnO-B ₂ O ₃ system, ZnO-B ₂ O ₃ -S
An iO ₂ system, a ZnO—B ₂ O ₃ —SiO ₂ —Al ₂ O ₃ system, and the like can be given. Among them, ZnO—B ₂ O ₃ and ZnO—
B ₂ O ₃ -SiO ₂ -based are preferred. The particle diameter of the glass component powder containing Zn and B is preferably 2 to 5 μm.
m, more preferably 3 to 4 μm.

When the total ratio of the calcined powder and the glass component powder is 100 parts by mass, (6
0-95) / (5-40) parts by mass, preferably (65-85) / (15-35) parts by mass, more preferably (70-80) / (20-30) parts by mass. When the compounding amount of the calcined powder is less than 60 parts by mass or the compounding amount of the glass component powder exceeds 40 parts by mass, the insulating properties and the dielectric properties are inferior, while the compounding amount of the calcined powder exceeds 95 parts by mass. Or the amount of the above glass component powder is 5
If the amount is less than 10 parts by mass, sintering at 1050 ° C. or lower is not preferred.

The molded body before firing can be obtained in the same manner as described above.
It is baked for 3 hours (preferably 1-2 hours). The firing temperature is 850 to 1050 ° C., preferably 900 to 1050.
00 ° C.

A wiring board according to the present invention is characterized in that low-temperature fired porcelain obtained by the manufacturing method according to claim 4 or 5 is laminated, and a wiring pattern is formed at least inside. Further, another wiring board of the present invention,
A low-temperature fired porcelain according to any one of claims 1 to 3 is laminated, and a wiring pattern is formed at least inside.

The wiring pattern may be formed inside at least one of the low-temperature fired ceramics to be laminated. The wiring pattern is preferably made of a low-resistance metal such as Ag, Au, and Cu. Regarding the wiring pattern formed outside the low-temperature fired porcelain, Ag, Au
Other than Cu and Cu, those having excellent solder characteristics such as Ag / Pd and Ag / Pt may be used. The present wiring board is usually printed according to a wiring pattern by screen printing or the like using a paste made of a low-resistance metal such as Ag, Au and Cu on a green sheet made of a composition that becomes a low-temperature fired porcelain by firing. It is obtained by stacking sheets and performing a baking treatment. In this wiring board, the number of laminated low-temperature fired ceramics is not limited as long as a wiring pattern is formed between the low-temperature fired ceramics.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the following examples. 1. Production of calcined powder After mixing each powder of ZnO, SiO ₂ and Al ₂ O ₃ so as to have the composition shown in Table 1, the powder was mixed in an air atmosphere at 1200 to 1400.
Calcination was performed at 2 ° C. for 2 hours to obtain calcined powders A to K. This AK
Was analyzed for crystallinity using an X-ray diffractometer (CuKα ray, manufactured by Rigaku Corporation).
It contained nAl ₂ O ₄ crystals, α-SiO ₂ crystals, and Zn ₂ SiO ₄ crystals. Further, in the X-ray diffraction measurement, the crystallinity was measured by a read belt method, and the mass ratio between the crystal phase and the glass phase was calculated. In Table 1, “S” is α
—SiO ₂ , “Z2S” represents Zn ₂ SiO ₄ , “ZA”
Represents ZnAl ₂ O ₄ , [C] represents cristobalite,
“Z” indicates ZnO and “A” indicates Al ₂ O ₃ .

[0038]

[Table 1]

2. Production of low-temperature fired porcelain (1) The calcined powders AK obtained above, MnO ₂ powder and B ₂ O ₃
The powders were mixed in the proportions shown in Table 2 and 750 to 750 in air atmosphere.
Calcination was performed at 850 ° C. for 2 hours, and then pulverization was performed. The obtained powder was granulated by adding an acrylic resin as a binder and methyl ethyl ketone as a solvent and granulating under a pressure of 80 MPa.
Molded. This was further subjected to CIP (isotropic isostatic pressing) treatment at a pressure of 150 MPa to obtain a molded body before firing. The molded body was fired at 900 to 1050 ° C. for 1 hour in the atmosphere to obtain low-temperature fired ceramic samples 1 to 8. The obtained samples were evaluated for the following items, and the results were shown in Tables 2 and 3.
It was shown to.

(A) Water absorption: Measured according to JIS C2141. (B) Thermal expansion coefficient α: Measured at a temperature of 30 to 400 ° C. (heating rate 5 ° C./min) using a differential expansion thermomechanical analyzer (compression load method, manufactured by Rigaku Corporation). Sample size is φ4 × 20
mm. (C) Flexural strength: Measured according to JIS R1601 (flexural strength by three-point bending). (JIS: 3 × 4, span: 30 mm) (d) Dielectric properties: Measured according to JIS R1627. (TE ₀₁₁ mode by parallel conductor plate type dielectric resonator method, resonance frequency is 9 to 13 GHz) In Table 2, ε _r is a dielectric constant, Q is a no-load quality factor, and f ₀ is a resonance frequency at 25 ° C. Is shown. (E) Content of alkali metal element and alkaline earth metal element The alkali metal element and alkaline earth metal element contained in the obtained low-temperature fired porcelain were qualitatively and quantitatively determined by X-ray fluorescence analysis. The unit is mass%.

[0041]

[Table 2]

The crystal content of each crystal phase in the obtained low-temperature fired porcelain was determined by X-ray diffraction measurement and is shown in Table 3. The unit is mass%.

[0043]

[Table 3]

3. Production of Low-Temperature Fired Porcelain (2) The calcined powders A to K obtained above, MnO ₂ powder, and powders of glass components having the following composition were mixed at the ratio shown in Table 4, and a binder was added to the obtained powder. Was granulated by adding methyl ethyl ketone as a solvent and granulating at a pressure of 80 MPa. This is further increased to 150
CIP (isotropic isostatic pressing) treatment was performed at MPa to obtain a molded body before firing. 850-500 in the air atmosphere
Fired at 1050 ° C for 1 hour, low-temperature fired porcelain samples 9 to 28
I got The obtained samples were evaluated for the above items, and the results are shown in Table 4, and the amount of each crystalline phase is shown in Table 5. still,
The unit of the numerical value in Table 5 is mass%, and the sample number 16
C in α-SiO ₂ (C) indicates cristobalite. Glass: SiO ₂ 10% by mass, B ₂ O ₃ 37% by mass, Z
nO 53 mass% glass: SiO ₂ 28 mass%, B ₂ O ₃ 46 mass%, A
l ₂ O ₃ 9% by weight, BaO17 wt% glass: SiO ₂ 61 wt%, B ₂ O ₃ 20 wt%, A
l ₂ O ₃ 10% by mass, MgO 1% by mass, CaO 1% by mass,
Na ₂ O 5% by mass, K ₂ O 2% by mass

[0045]

[Table 4]

[0046]

[Table 5]

4. Manufacture of wiring board Acrylic resin as a binder and dibutyl phthalate, dioctyl phthalate and the like as a plasticizer were added to the raw material components of Samples 1 to 28, and a slurry was prepared with a solvent such as toluene, methyl ethyl ketone and alcohol, and the doctor blade method was used. Thus, a green sheet having a thickness of 0.3 mm was obtained. A wiring pattern was printed on this sheet using a paste made of Ag or Cu. After laminating four green sheets, when using a paste made of Ag, the resin is heated at 850-900 ° C. for 2 hours in the air, and when using a paste made of Cu, the resin is dried at 650-800 ° C. for 9 hours under a wet nitrogen atmosphere. Punching, then 900 under nitrogen atmosphere
It was baked at 1050 ° C. for 2 hours to obtain a wiring board. With respect to the obtained wiring board, the co-sintering property with metallization was evaluated by the state of diffusion of the wiring material (Cu) into the board, and the results are shown in Tables 2 and 3.

From the results shown in Table 2, it can be seen that Sample 1 was made of Al_TwoO_ThreeLow component
No, ZnAl_TwoO_FourLow bending strength due to small amount of crystals
Degree has decreased. Sample 5 is B_TwoO_ThreeBecause there are too many ingredients,
As the liquid phase exudes, the no-load quality factor decreases,
Strength decreased. Sample 8 is B_TwoO_ThreeLow in ingredients
Because of this, densification did not occur even at a firing temperature of 1100 ° C. one
On the other hand, Samples 2, 3, 4, 6 and 7 have thermal expansion coefficients and
Excellent for each item of degree, dielectric constant and no-load quality factor
Performance was shown. Samples 6 and 7 show particularly good performance
Was. From Table 3, Samples 9 and 24 show that Al in calcined powder A_Two
O_ThreeLow component, ZnAl _TwoO_FourLow amount of crystal formation
As a result, the bending strength decreased. Sample 12 is a glass component
Does not densify even at firing temperature of 1100 ° C
Was. Samples 14 and 15 are glasses containing Zn and B
Because no was used, the no-load quality factor was reduced. In particular
Since sample 15 contains a large amount of alkali metal, resonance
No waveform was obtained. Sample 16 had a calcining temperature of 140
As high as 0 ° C, cristobalite is generated by calcination,
The obtained sintered body has an inflection point. Ma
In addition, the sample 23 contains MnO_TwoIs too large and the dielectric constant
Exceeded 7, and the no-load quality factor further decreased. On the other hand, Z
Sample 1 obtained using glass containing n and B
0, 11, 17 to 22, 25 to 28 are all 105
Densified below 0 ° C, ZnAl as main crystal_TwoO_Fourcrystal,
α-SiO_TwoCrystal, Zn_TwoSiO_FourIt contained crystals.
This material has excellent dielectric properties (low dielectric constant, low dielectric constant) in the high frequency range.
Dielectric loss) and high bending strength was obtained.

Each of the wiring boards obtained as described above is densified at 1050 ° C. or less, and ZnAl ₂ O ₄ crystal is used as a main crystal, α-SiO ₂ crystal, Zn ₂ Si
It contained O ₄ crystals. The reaction with metallization was small, and the metallized portion was good with little warpage and undulation. This wiring board has a coefficient of thermal expansion close to that of GaAs or the like, has excellent matching properties, and has a high bending strength, so that the bonding property with metal fittings is also improved. Furthermore, it has excellent dielectric properties (low dielectric loss and low dielectric constant) and can be co-fired with low resistance wiring, so that it is easy to handle.

[0050]

According to the low-temperature fired porcelain of the present invention, ZnA
It is composed of a main crystal of l ₂ O _4, a crystal phase composed of α-SiO ₂ crystal and Zn ₂ SiO ₄ crystal and a residual glass phase, and contains no alkali metal and alkaline earth metal, so that water absorption and thermal expansion coefficient can be improved. Excellent in bending strength, dielectric constant and no-load quality factor. According to the method for producing a low-temperature fired porcelain of the present invention, not only glass powder but also ZnAl ₂ O ₄ crystal, α-SiO ₂ crystal, Zn ₂ Si
By forming a calcined powder containing at least one crystal selected from O ₄ crystal, Al ₂ O ₃ crystal and ZnO crystal and a small amount of glass powder, a dense sintered body is obtained by firing at 1050 ° C. or less. A material having excellent dielectric properties in a high-frequency region, having little reaction with metallization even when co-firing with metallization, and hardly causing warpage and undulation can be obtained. Further, according to the wiring substrate of the present invention, a substrate having excellent dielectric properties and having less warpage or undulation of the metallized portion can be obtained.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor: Manabu Sato 14-18 Takatsuji-cho, Mizuho-ku, Nagoya Japan F-term (reference) 4G030 AA14 AA16 AA22 AA25 AA28 AA29 AA32 AA35 AA36 AA37 BA09 CA01 GA08 GA14 GA15 GA17 GA20 GA21 GA22 GA25 GA27 5E346 AA12 AA15 BB01 CC18 CC32 CC38 CC39 DD34 EE24 EE25 GG02 GG09 HH06 HH11

Claims (7)

[Claims] 1. It comprises a main crystal of ZnAl ₂ O ₄ , a crystal phase of α-SiO ₂ crystal and Zn ₂ SiO ₄ crystal, and a remaining glass phase, and does not substantially contain an alkali metal element and an alkaline earth metal element. A low-temperature fired porcelain. 2. The crystal phase in a low-temperature fired porcelain is ZnAl ₂
30 to 80% by mass of O ₄ crystals, 0 to 40% by mass of α-SiO ₂ crystals, and 0 to 50% by mass of Zn ₂ SiO ₄ crystals.
A low-temperature firing porcelain containing nO ₂ 0 to 5% by weight and B ₂ O ₃ 2 to 15% by weight, low-temperature firing porcelain which is characterized by containing substantially no alkali metal element and alkaline earth metal elements . 3. A water absorption rate is 0.1% or less, a thermal expansion coefficient is more than 3 ppm / ° C. and less than 9 ppm / ° C., a transverse rupture strength is 150 MPa or more, a dielectric constant is 7 or less, The low-temperature fired porcelain according to claim 1 or 2, wherein a no-load quality factor in a 9 to 13 GHz region is 800 or more. 4. A calcined powder 85-containing ZnAl ₂ O ₄ crystal and at least one crystal selected from α-SiO ₂ crystal, Zn ₂ SiO ₄ crystal, Al ₂ O ₃ crystal and ZnO crystal. 98% by mass and _{2 to} 15% by mass of B ₂ O ₃ powder are mixed and molded, and the molded body is calcined at 850 to 1050 ° C. to obtain a low-temperature calcined porcelain having ZnAl ₂ O ₄ crystal as a main crystal. A method for producing a low-temperature fired porcelain. 5. A calcined powder 60 containing ZnAl ₂ O ₄ crystal and at least one crystal selected from α-SiO ₂ crystal, Zn ₂ SiO ₄ crystal, Al ₂ O ₃ crystal and ZnO crystal. ９５95% by mass and 5-40% by mass of a glass component powder containing Zn and B are mixed and molded, and the molded body is fired at 850５０1050 ° C. to make ZnAl ₂ O ₄ crystal a main crystal. A method for producing a low-temperature fired porcelain, comprising obtaining a low-temperature fired porcelain. 6. A wiring board, wherein low-temperature fired porcelain obtained by the manufacturing method according to claim 4 or 5 is laminated, and a wiring pattern is formed at least inside. 7. A wiring board comprising the low-temperature fired porcelain according to claim 1 and a wiring pattern formed therein at least.