JPH08295558A - Glass-ceramic sintered compact and its manufacture - Google Patents

Abstract

PURPOSE: To produce a sintered compact which has high permittivity and high strength and is formed from a green compact that can be simultaneously sintered together with metallic wiring by using a green compact contg. at least Zr, Ca, Si, Al, Mg, Zn and B metallic elements for forming a sintered compact contg. ZrO2 crystal phases, spinel type crystal phases, anorthite type crystal phases and a glass phase. CONSTITUTION: In this manufacture, 30 to 70wt.% of SiO2 -Al2 O3 -MgO-ZnO-B2 O3 based glass and 70 to 30wt.% of the total amount in terms of oxide of Ca oxide and Zr oxide (optionally in the form of a compound consisting of them) which are used as filler components are mixed together to obtain a powdery mixture and an adequate amount of a binder is added to the powdery mixture and, thereafter, the resultant mixture is formed into a green compact. Then, the green compact is sintered in a non-oxidizing atmosphere at 800 to 950 deg.C for 0.1 to 5 hours to manufacture the objective sintered compact contg. ZrO2 crystal phases 1, spinel type crystal phases 2, anorthite type crystal phases 3 and a glass phase 5. To manufacture a wiring substrate by using this sintered compact, the above powdery mixture is formed into a green sheet for forming an insulating layer, and then, a wiring pattern is printed on the surface of the green sheet with a metallic paste by a screen process, and simultaneous sintering of the resultant wiring layer and the insulating layer is performed under the above sintering conditions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass-ceramic sintered body and a method for manufacturing the same, and for example, a glass-ceramic sintered body most suitable for a substrate for mounting an integrated circuit (IC) or electronic parts. The present invention relates to a body and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, with the era of advanced information, information transmission tends to be faster and higher in frequency. In mobile radio such as car telephones and personal radios, satellite broadcasting, satellite communications, and new media such as CATV, downsizing of devices is being promoted, and accordingly, microwave circuit elements such as dielectric resonators are being promoted. However, miniaturization is strongly desired.

The size of such a microwave circuit element is based on the wavelength of the electromagnetic wave used. The wavelength λ of the electromagnetic wave propagating through the dielectric having the relative permittivity εr is λ = λ ₀ / (εr) ^1/2 when the propagation wavelength in vacuum is λ ₀ . Therefore, the larger the dielectric constant of the circuit board used, the smaller the size of the circuit element.

Further, in order to prevent the substrate from being broken or chipped due to the stress applied to the substrate in the process of connecting various electronic parts, input / output terminals, etc. to the multilayer circuit board, a mechanical material is used. High strength is also required.

Therefore, in order to satisfy the above-mentioned demands for high permittivity and high strength, for example, Japanese Patent Laid-Open No. 06-13
As disclosed in Japanese Patent No. 2621, there has been proposed a circuit board in which inorganic dielectric particles are dispersed in a resin and which is reinforced with a high dielectric constant glass fiber. Since this circuit board has a high relative dielectric constant, it can promote miniaturization of equipment, and has high strength because it is reinforced with a high dielectric constant glass fiber.

[0006]

However, in the circuit board disclosed in Japanese Patent Laid-Open No. 06-132621,
Since the firing temperature is about 400 ° C., there is a problem that it is impossible to form a multilayer and fine wiring by using copper or the like as a wiring conductor.

Therefore, according to the present invention, a glass having a high relative permittivity and a high strength is used while being fired at 800 to 950 ° C. so that gold, silver and copper can be used as a wiring conductor to form a multilayer.
It is an object to provide a ceramic sintered body and a method for manufacturing the same.

[0008]

Means for Solving the Problems The inventors of the present invention have made earnest studies on the above-mentioned problems, and as a result, fired at 800 to 950 ° C. by utilizing the softening flow of glass, whereby gold, silver and By using copper, multi-layering and fine wiring are possible, and by combining high-dielectric-constant zirconia and calcium compounds and specific glass, ZrO ₂ and anorthite are precipitated as crystal phases. A high relative permittivity can be obtained, and a spinel type crystal phase (MgO.Al ₂ O ₃ , ZnO.Al ₂ O
It was found that high strength can be achieved by precipitating ₃ ), and the present invention was accomplished.

That is, the glass-ceramic sintered body of the present invention contains at least Zr, Ca, Si and A as metal elements.
70% to 30% by weight in terms of oxide of Zr and Ca, including Si, Al, Mg, Zn and B, and Si, Al,
The total amount of Mg, Zn and B converted to oxide is 30 to 7
A glass-ceramic sintered body containing 0% by weight, characterized in that the sintered body contains a ZrO ₂ crystal phase, a spinel type crystal phase, an anorthite type crystal phase and a glass phase. As a method for producing such a sintered body, SiO ₂ , Al ₂ O ₃ , MgO, ZnO and B ₂
After molding a mixed powder obtained by mixing 30 to 70% by weight of glass made of O ₃ with Ca oxide and Zr oxide or a compound thereof at a ratio of 70 to 30% by weight in total in terms of oxide, It is characterized by firing in an oxidizing atmosphere at 800 ° C to 950 ° C.

Here, the composition in the glass-ceramic sintered body is limited to the above range by Si, Al, M.
The total amount of g, Zn and B converted to oxides is 30% by weight.
If it is less, in other words, if the total amount of Zr and Ca calculated as oxides is more than 70% by weight, it is 800 to 950.
The porcelain could not be fully densified at a temperature of ℃,
Is the total amount of i, Al, Mg, Zn and B calculated as oxides more than 70% by weight, in other words Zr and Ca?
This is because the dielectric constant becomes lower than 9 when the total amount of the oxide conversion is less than 30% by weight.

Zr is 15 in the total amount in terms of ZrO _2.
˜69 wt%, and Ca is preferably in the range of 1 to 33 wt% in terms of CaO in the total amount. It has a Zr content of 15
If it is less than wt%, the dielectric constant of porcelain is lower than 9 and 6
If it is more than 9% by weight, the densification temperature of the porcelain is 1000 ° C.
This is because it becomes higher and the copper conductor cannot be used. Further, if the Ca content is less than 1% by weight, the densification temperature of the porcelain becomes higher than 950 ° C., which greatly deviates from the shrinkage curve of copper and the copper conductor peels off. This is because the dielectric constant becomes lower than 9.

According to the present invention, the Zr content and Ca content are ZrO _{2 in} particular because of the relationship between the dielectric constant and the bending strength.
30 to 60% by weight in terms of conversion, Ca is 0.01 in terms of CaO
It is desirable that the content is ˜30 wt%.

A schematic diagram of the structure of the glass-ceramic sintered body of the present invention is shown in FIG. As shown in FIG. 1, the glass-ceramic sintered body of the present invention has a ZrO ₂ crystal phase 1
And a spinel-type crystal phase 2, an an-site-type crystal 3, and a glass phase 5 composed of SiO ₂ —Al ₂ O ₃ —MgO—ZnO—B ₂ O ₃ . The ZrO ₂ crystal phase 1 constitutes the main crystal in the sintered body and is composed of tetragonal ZrO 2.
Exists as ₂ . The spinel type crystal phase is MgO.
It is a crystal of Al ₂ O ₃ or ZnO.Al ₂ O ₃ . Further, as the anorthite type crystal phase, CaAl ₂ Si ₂ O is used.
₈ crystals. Further, in this sintered body, other phases 4 of the garnite phase and the cordierite phase may be further precipitated, but it is preferable that the number of these crystals is as small as possible.

As described above, according to the present invention, the relative permittivity can be improved by making the zirconia (tetragonal) phase mainly exist in the sintered body. Further, the spinel type crystal phase is precipitated in the sintered body by adjusting the firing temperature. Since these crystal phases exist in a form that reinforces the glass network, a sintered body having high mechanical strength can be obtained.

However, if the crystallization of glass progresses and the spinel type crystal phase increases too much, the relative dielectric constant may decrease. Therefore, by setting the firing temperature to 800 ° C. to 950 ° C., the mechanical strength is high and the ratio is high. A sintered body having a dielectric constant of 9 to 10 can be obtained.

Next, in order to manufacture the glass-ceramic sintered body of the present invention, SiO ₂ -Al ₂ O is used as a starting material.
₃ and -MgO-ZnO-B ₂ O ₃ based glass 30-70 wt%, the Ca oxide and Zr oxide or a compound thereof as a filler component in a total amount of oxide conversion 70
Mix so that the proportion is about 30% by weight.

[0017] As the filler component, in addition to be added in powder or ZrO _2, carbonates capable of forming a ZrO _2, CaO during sintering, a nitrate, in the form of such as acetic acid salt, ZrO ₂
It can also be added in the form of CaZrO ₃ as a compound of CaO and CaO. In the composition, Zr is Zr
O ₂ fifteen to sixty-nine wt% in terms of, Ca is 1 in terms of CaO
It is desirable to mix it in a proportion of 33% by weight. Note that C
It is important that the a compound precipitates an anorthite type crystal phase by a reaction with glass. From this viewpoint, Ca
The compound or CaZrO ₃ powder is 1.5 μm or less,
In particular, it is desirable that the fine powder is 1.0 μm or less.

The filler component ZrO ₂ is Y
It is desirable to add a stabilizer such as ₂ O ₃ in the form of tetragonal ZrO ₂ or cubic ZrO ₂ .
This is because, in the case of monoclinic zirconia, phase transformation occurs depending on the temperature, and a crack or the like occurs in the substrate due to the volume change caused by the temperature transformation.

Further, as a starting material, SiO ₂ --Al
_{The 2} O ₃ -MgO-ZnO-B ₂ O ₃ type glass is used because the spinel type crystal phase is precipitated by using this type of glass, and this crystal phase exists in a form that reinforces the network of the glass. This is because a high-strength sintered body can be obtained. In addition, the glass of such a system is 30 to 70
When the amount of glass is less than 30% by weight, the densification temperature of the sintered body is higher than 1000 ° C and the copper conductor cannot be used, and the amount of glass is 70% by weight.
This is because the bending strength of the porcelain decreases when the amount is larger.

This SiO ₂ --Al ₂ O ₃ --MgO--Zn
The amount of OB ₂ O ₃ based glass added is preferably 40 to 60% by weight, more preferably 40 to 50% by weight. _{SiO 2 -Al 2 O 3 -MgO-} ZnO
As a more specific composition of —B ₂ O ₃ based glass, SiO 2 is used.
₂ : 40 to 45% by weight, Al ₂ O ₃ : 25 to 30% by weight, MgO: 8 to 12% by weight, ZnO: 6 to 9% by weight,
B ₂ O _3: 8~11 wt% is desirable.

After properly adding a binder to the mixed powder which is added and mixed in the above proportions, it is molded into a predetermined shape and N
₂ , 800 ° C to 95 in a non-oxidizing atmosphere such as Ar
It is obtained by firing at 0 ° C. for 0.1 to 5 hours. If the firing temperature at this time is lower than 800 ° C, the porcelain will not be sufficiently densified, and if it exceeds 950 ° C, the copper conductor cannot be used, and further, the anorthite type crystal that contributes to higher permittivity is decomposed. However, a low-permittivity garnite or cordierite is generated and the characteristics deteriorate.

When a wiring board is manufactured using such glass ceramics, the mixed powder prepared as described above is insulated by a known tape molding method such as a doctor blade method or a rolling method. After producing a green sheet for forming a layer, as a metallization for a wiring layer on the surface of the sheet, powder of Ag, Au or Cu, particularly Cu
A metal paste containing powder is used to screen-print a wiring pattern on the surface of the sheet, and in some cases a through hole is formed in the sheet to fill the hole with the paste. After that, a plurality of sheets are laminated and pressure-bonded, and then the wiring layer and the insulating layer can be simultaneously fired by firing under the above-described conditions.

[0023]

According to the glass-ceramic sintered body of the present invention,
By including Zr oxide and Ca oxide as a filler component, a high dielectric constant ZrO ₂ crystal phase is precipitated, and by reacting a part of the glass component with Ca, an anorthite type crystal phase is precipitated, resulting in a low dielectric constant. The dielectric constant of the whole sintered body can be increased by reducing the amount of glass. Also,
By mixing Ca oxide as a filler component together with the SiO ₂ —Al ₂ O ₃ —MgO—ZnO—B ₂ O ₃ based glass, a spinel type crystal layer is precipitated from this glass component, and thus the resistance of the sintered body is improved. Folding strength can be increased.

The glass-ceramic sintered body is
Since it can be fired at the temperature of 800 to 950 ° C. at the same time as the internal wiring layers of Au, Ag, or Cu, it is possible to easily achieve the fine wiring of the multilayer wiring board or the package for housing the semiconductor element, which includes these wiring conductors. .

[0025]

EXAMPLES _{SiO 2 -Al 2 O 3 -MgO-} ZnO-B
₂ O ₃ type crystalline glass A (SiO ₂ : 44% by weight, Al
₂ O ₃ : 29% by weight, MgO: 11% by weight, ZnO: 7
% By weight, B ₂ O ₃ : 9% by weight), and ZrO ₂ and CaCO ₃ having an average particle size of 1 μm or less were mixed according to the composition shown in Table 1. In Table 1, samples No. 1, 2, 3, 6, 10,
For 13, 15, 16 Ca with an average particle size of 0.7 μm
ZrO ₃ powder was added.

Then, an organic binder, a plasticizer and toluene were added to this mixture, and a green sheet having a thickness of 300 μm was prepared by the doctor blade method. Then, 5 sheets of this green sheet are laminated and 100 at a temperature of 50 ° C.
A pressure of kg / cm ₂ was applied for thermocompression bonding. The obtained laminate was debindered at 700 ° C. in a water vapor-containing / nitrogen atmosphere, and then fired in dry nitrogen under the conditions shown in Table 1 to obtain a glass ceramic sintered body.

The dielectric constant and bending strength of the obtained sintered body were evaluated by the following methods. Dielectric constant is sample shape diameter 5
A sample with a thickness of 0 mm and a thickness of 1 mm was cut out and measured by a cavity resonator method using a network analyzer and a synthesized sweeper. In the measurement, the sample dielectric substrate was sandwiched between the sapphire-filled cylindrical resonators. The dielectric constant was calculated from the resonance characteristics of the TE011 mode of the resonator. The bending strength was such that the sample shape had a length of 70 mm, a thickness of 3 mm, and a width of 4 mm, and a three-point bending test was conducted according to JIS-C-2141. The measurement results are shown in Table 1.

As a comparative example, a sintered body was similarly prepared by using Al ₂ O ₃ and forsterite instead of ZrO ₂ or CaO as a filler component and evaluated (Sample Nos. 17 and 18). Further, instead of the crystallized glass,
SiO ₂ : 55.2% by weight, Al ₂ O ₃ : 12% by weight,
B ₂ O _3: 4.4 wt%, MgO: 20 wt%, Zn
O: 6.7% by weight, Na ₂ O 1.6% by weight, ZrO
₂ Crystallized glass B having a composition of 0.1% by weight, SiO ₂ : 6
0.7% by weight, Al ₂ O ₃ : 9.3% by weight, B ₂ O ₃ :
Crystallized glass C having a composition of 5 wt%, MgO: 15.4 wt%, ZnO 8.6 wt%, and K ₂ O 1 wt% was used, and CaZr having an average particle size of 0.7 μm was used as a filler.
The O ₃ were evaluated in the same manner using (Sample No.19,20).

[0029]

[Table 1]

As is clear from the results of Table 1, in the present invention in which ZrO ₂ , spinel and anorthite were precipitated as the crystal phase, the dielectric constant was 9 or more and the strength was 20 kg /
It shows a high value of mm ² or more. Among these, those having a firing temperature of 830 to 900 ° C. have a dielectric constant of 11 or more and a strength of 2
It was as high as 3 kg / mm ² or more.

On the other hand, in the sample No. 1 in which the contents of ZrO ₂ and CaO exceed 70% by weight, the densification cannot be achieved unless the firing temperature is raised to 1200 ° C. and the relative dielectric constant is low. Met. In addition, ZrO ₂ and Ca
In the sample No. 16 in which the O content is less than 30% by weight,
Although ZrO ₂ was deposited, both the dielectric constant and the strength were low.

As a comparative example, Al is used as a filler.
_The dielectric constants of sample No. 17 using ₂ O ₃ and sample No. 18 using forsterite were 5 and 4.5, respectively. In addition, the sample No. using the crystallized glass B and C.
In Nos. 19 and 20, the densification could not be sufficiently carried out at 800 ° C to 950 ° C, and neither of the sintered bodies had high dielectric constant and high strength.

[0033]

As described in detail above, since the glass-ceramic sintered body of the present invention has a high dielectric constant and strength,
It is possible to miniaturize microwave circuit elements etc.,
Further, by increasing the strength of the substrate material, it is possible to improve the reliability of the substrate in joining the leads to the input / output terminal portion and mounting. Moreover, since it is fired at 800 to 950 ° C, A
Wiring made of u, Ag, Cu or the like can be formed by simultaneous firing.

[Brief description of drawings]

FIG. 1 is a schematic view of the structure of a glass-ceramic sintered body of the present invention.

[Explanation of symbols]

1 ZrO ₂ crystal phase 2 spinel type crystal phase 3 anorthite type crystal 5 glass phase

Claims (2)

[Claims] 1. A metal element comprising at least Zr, Ca,
Includes Si, Al, Mg, Zn and B, Zr and C
70 to 30 wt% of the total amount of a in terms of oxide
And a glass-ceramic sintered body containing Si, Al, Mg, Zn and B in a total amount of 30 to 70% by weight in terms of oxide, wherein the sintered body contains a ZrO ₂ crystal phase,
A glass-ceramic sintered body comprising a spinel type crystal phase, an anorthite type crystal phase and a glass phase. 2. At least SiO ₂ , Al ₂ O ₃ , Mg
A mixture of 30 to 70% by weight of glass containing O, ZnO and B ₂ O ₃ and 70 to 30% by weight of Ca oxide and Zr oxide or their compounds in terms of total oxide equivalent. 800 ℃ ~ 950 after molding the powder
A method for producing a glass-ceramic sintered body, which comprises firing at ℃.