JPH1160266A - Glass and glass ceramic material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a ceramic material with low dielectric constant and sufficient mechanical strength by mixing a ceramic with a glass comprising SiO2 , BaO, La2 O3 , B2 O3 , Al2 O3 and K2 O in specified weight proportions. SOLUTION: This glass ceramic material, a glass/ceramic sintered compact, is obtained by mixing a specified amount of a ceramic of a ceramic powder with glass powder comprising 40-50 wt.% of SiO2 , 30-40 wt.% of BaO, 7-13 wt.% of La2 O3 , 3-8 wt.% of B2 O3 , 3-8 wt.% of Al2 O3 and 1.5-2.5 wt.% of K2 O followed by kneading together with a solvent such as polyvinyl butyral resin, dibutyl phthalate or vinyl acetate and a binder, conducting molding and then sintering. When the ceramic powder is alumina powder, the average particle size is <=2.0 μm and the amount to be mixed is 25-40 pts.wt. based on 100 pts.wt. of the composition, while for forsterite powder, the average particle size is <=2.5 μm and the amount to be mixed is 30-45 pts.wt. The glass powder to be used is <=3.5 μm in average particle size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass and a glass-ceramic material, and more particularly to a glass capable of obtaining a sufficient wettability with a ceramic at the time of co-firing with a ceramic even at a low temperature, and having a low dielectric constant and a sufficient mechanical strength. And a glass ceramic material that can be fired at a low temperature.

[0002]

2. Description of the Related Art In recent years, as the frequency used in the communication field has been increased, the electronic components used in communication equipment have been required to cope with the higher frequency. Further, in order to respond to the demand for miniaturization of communication equipment, miniaturization of electronic components is also required.

Conventionally, alumina having a low relative dielectric constant has been widely used as a substrate material for high-frequency components. However, alumina has a high firing temperature and cannot be fired simultaneously with a conductor material. On the other hand, a multilayer structure composed of a plurality of conductor layers and a substrate material layer is advantageous for miniaturization of electronic components, but it is difficult to realize high-frequency electronic components using alumina for the above-described reasons. Was.

Therefore, glass ceramic materials are being used as substrate materials which have a low relative dielectric constant and can be co-fired with a conductor material. For example, Japanese Unexamined Patent Publication No.
In the low-temperature sintering substrate described in Japanese Patent Application Laid-Open No. 2-26864, a low dielectric constant substrate is realized by uniformly providing ultrafine pores in a crystallized glass-based material. In the method for manufacturing a low-temperature fired substrate, a material that has a low dielectric constant and can be fired at low temperature is realized by a glass ceramic composite material in which glass powder and alumina powder are mixed.

[0005]

However, in the former case, the mechanical strength of the substrate is as small as 1100 kgf / cm ^2, and in the latter case, lead oxide is used as a glass material, which is problematic in terms of environmental problems. .

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a glass capable of obtaining a sufficient wettability with the ceramic even at a low temperature at the time of co-firing with the ceramic, and having a low dielectric constant and sufficient mechanical strength. It is another object of the present invention to provide a glass-ceramic material having sufficient sinterability even at a low temperature that can be co-fired with a conductor material.

[0007]

According to the present invention, there is provided a glass wherein the constituents are SiO ₂ = 40 to 50 by weight percentage.
%, BaO = 30~40%, La 2 O 3 = 7~13%, B
₂ O ₃ = 3 to 8%, Al ₂ O ₃ = 3 to 8%, K ₂ O = 1.5
~ 2.5% of the composition.

The glass ceramic material is characterized in that its constituent components are a mixture of the glass powder and the ceramic powder.

According to this structure, by optimizing the composition of the glass and the glass-ceramic material, the glass which can obtain sufficient wettability with the ceramic even at a low temperature during the simultaneous firing with the ceramic, and the low dielectric constant sufficient It is possible to obtain a glass-ceramic material having mechanical strength and sufficient sinterability even at a low temperature at which co-firing with the conductor material is possible.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention
Means that the glass is SiO 2 in weight percent_Two= 40-50%, B
aO = 30-40%, La_TwoO_Three= 7-13%, B_TwoO_Three=
3-8%, Al _TwoO_Three= 3-8%, K_TwoO = 1.5-2.
It is characterized by having a composition of 5%.
The glass is kept at a low temperature during simultaneous firing with ceramics
However, sufficient wettability with the ceramics can be obtained.
Wear.

The invention according to claim 2 is characterized in that the glass-ceramic material comprises a mixture of the glass powder and the ceramic powder, whereby the fired body of the glass-ceramic material has a low dielectric constant. At the same time, it has sufficient mechanical strength and can obtain sufficient sinterability even at a low temperature where it can be co-fired with the conductor material.

[0012] The invention according to claim 3 is characterized in that the ceramic powder is alumina, whereby the mechanical strength can be further improved.

[0013] The invention described in claim 4 is characterized in that the ceramic powder is forsterite, whereby the dielectric constant and the firing temperature can be further reduced.

[0014] The invention according to claim 5 is characterized in that:
The content of alumina in 00 parts by weight is not less than 25 parts by weight and less than 40 parts by weight,
Thereby, the mechanical strength is further improved, and the firing temperature can be lowered.

[0015] The invention according to claim 6 is a method according to claim 6, wherein
Forsterite content in 00 parts by weight is 30
The amount is not less than 45 parts by weight and not more than 45 parts by weight, whereby the dielectric constant and the firing temperature can be further reduced.

The invention according to claim 7 is characterized in that the average particle diameter of the glass powder is 3.5 μm or less, whereby the firing temperature can be lowered and the mechanical strength can be further improved. It becomes possible.

The invention according to claim 8 is characterized in that the average particle size of the alumina is 2.0 μm or less, which makes it possible to further reduce the firing temperature and improve the mechanical strength. Become.

According to a ninth aspect of the present invention, the average particle size of the forsterite is 2.5 μm or less, whereby the firing temperature can be lowered and the mechanical strength can be further improved. Becomes

Hereinafter, an embodiment of the present invention will be described.
Preparation of a green sheet of a ceramic substrate material was performed as follows.

The glass was prepared by crushing a glass melt in a platinum crucible using oxides, carbonates and the like of the constituent components in the glass. Further, as the ceramic powder, alumina powder, zirconia powder, magnesia powder and forsterite powder (purity 96%, average particle size 0.8 to 3.0 μm)
Was used. A mixture of the glass and ceramic powder was used as a glass ceramic material.

500 g of the glass ceramic material was added to a solution of 25 g of dibutyl phthalate and 50 g of polyvinyl butyral resin in 300 g of butyl acetate, and mixed with a ball mill for 24 hours. A green sheet having a thickness of 100 μm was prepared from the obtained slurry by a known doctor blade method.

The green sheets were laminated and thermocompression-bonded at 80 ° C. to produce a green sheet laminate having a thickness of 2 mm, and then fired at a temperature of 900 ° C. to 950 ° C.

[0023]

Embodiments Specific embodiments will be described below.

The glass used in the glass-ceramic material composition in the above-mentioned embodiment is such that the components are SiO ₂ = 40 to 50% and BaO = 30 to 40 by weight percentage.
%, La ₂ O ₃ = 7 to 13%, B ₂ O ₃ = 3 to 8%, Al ₂
A composition having a composition of O ₃ = 3 to 8% and K ₂ O = 1.5 to 2.5% was used. The glass and the alumina powder, the zirconia powder, the magnesia powder, and the forsterite powder were mixed at various mixing ratios to obtain a glass ceramic material. The particle size of the above glass powder and ceramic powder was measured using a laser diffraction particle size distribution analyzer SAL manufactured by Shimadzu Corporation.
It measured with D-2000A.

In order to evaluate the wettability between the glass powder and the ceramic powder of the fired body substrate manufactured using the above glass ceramic material, an SEM (scanning electron microscope) of the fracture surface of the fired glass ceramic material substrate was used. Observations were made.

Further, the bending strength of the fired substrate manufactured using the above glass ceramic material was measured.
An Autograph AG-E type manufactured by Shimadzu Corporation was used for the measurement.

Further, in order to grasp the firing temperature of the glass ceramic material, differential thermal analysis (DTA) was performed. For measurement, Seiko Denshi Kogyo Co., Ltd.
G / DTA320 was used.

The relative permittivity and loss (tan δ) of the fired glass ceramic material substrate were measured. Hewlett-Packard Material Analyzer HP4 for measurement
291A was used.

Further, the surface roughness of the glass-ceramic material fired body substrate was determined by Feinpreff Perthen Gm.
It was measured with a bH surface meter Perthometer S8P.

The evaluation results of the fired glass and glass ceramic material substrates are shown in Tables 1 to 8 and FIGS.
(B). In Tables 1 to 8, those marked with * are out of the scope of the present invention, and all others are within the scope of the present invention. (Table 1)-
The results in Table 8 and FIGS. 1A and 1B were determined according to the following criteria.

Sintering temperature: 950 ° C. or less Relative permittivity: 8.0 or less under the condition of 1 GHz tan δ: 20 × 10 ⁻⁴ or less Bending strength: 1500 kgf / cm ² or more

[0032]

[Table 1]

[0033]

[Table 2]

[0034]

[Table 3]

[0035]

[Table 4]

[0036]

[Table 5]

Tables 1 to 5 show that the mixing ratio of the glass powder and the ceramic powder was maintained at 65:35 by weight percentage, and the composition of the glass was changed while keeping the respective particle diameters constant. FIG. 9 shows the characteristics of the fired body substrate in the case of FIG.

The glass composition contained in the glass ceramic material of the present invention is limited as described above for the following reasons.

SiO ₂ is a main component of glass. SiO ₂
If the content is 40% or less, vitrification does not occur, and if the content is 50% or more, the wettability with the ceramic powder deteriorates, so that in any case, a dense glass ceramic fired body cannot be obtained. .

BaO is a component that improves the wettability with ceramic powder during low-temperature firing. When the content is less than 30%, the effect of improving the wettability is not obtained. Devitrification easily occurs during molding. Therefore, in any case, a dense glass ceramic fired body cannot be obtained.

La ₂ O ₃ is a component for adjusting the viscosity of the glass at the time of firing at a low temperature. When the content is 7% or less, the viscosity does not decrease at the time of low-temperature firing, the wettability with the ceramic powder is deteriorated, and a dense fired body cannot be obtained. On the other hand, when the content is 13% or more, the viscosity is too low, and the strength is lowered, and disadvantages such as adhesion to a setter occur.

B ₂ O ₃ has a function as a flux component to improve the solubility at the time of melting. When the content is 3% or less, the effect is not obtained, and when the content is 8% or more, heat resistance and strength are undesirably reduced.

Al ₂ O ₃ is a component for improving heat resistance. When the content is 3% or less, heat resistance is insufficient, and 8%
% Or more, the glass tends to be devitrified at the time of forming the glass, so that it is impossible to obtain a dense fired glass ceramic body.

K ₂ O, as a flux component, has the effect of improving the solubility during melting. Its content is 1.5%
In the following cases, the effect is not obtained, and when it is 2.5% or more, the heat resistance decreases.

[0045]

[Table 6]

[0046]

[Table 7]

[0047]

[Table 8]

Tables 6 to 8 show the characteristics of the glass-ceramic fired body when the glass composition is kept constant and the mixing ratio of the glass and the ceramic powder is kept constant while the particle size of each of them is kept constant. Is represented.

When alumina is used as the ceramic powder, if the content is 25% or less by weight in the glass ceramic material, the strength is insufficient. Also, 40%
In the above case, the firing temperature becomes high.

When forsterite is used as the ceramic powder, if the content is 30% or less by weight in the glass ceramic material, the strength is insufficient. When the content is 45% or more, the firing temperature becomes high.

When zirconia is used as the ceramic powder, the relative dielectric constant of the fired glass ceramic becomes high, which is not preferable as a substrate material for high frequency components.

When magnesia is used as the ceramic powder, a dense sintered glass ceramic cannot be obtained. In addition, tan δ increases, which is not preferable as a material for a high-frequency circuit board.

FIGS. 1 (a) and 1 (b) show that the glass composition is kept constant, the mixing ratio of the glass powder and the ceramic powder is kept constant, and the particle diameters of the glass powder and the ceramic powder are changed. It shows the characteristics of the glass ceramic fired body in the case of the above. However, when the particle diameter of the glass powder was changed, the ceramic powder was alumina, and the average particle diameter was 1.0.
μm was used. When the average particle size of the alumina powder and the forsterite powder was changed, a glass powder having an average particle size of 3.0 μm was used.

When the average particle diameter of the glass powder is 3.5 μm or more, the surface roughness of the fired glass ceramic becomes rough.
When the average particle size of alumina is 2.0 μm or more or the average particle size of forsterite is 2.5 μm or more, it is possible to obtain a dense fired body in addition to a rough surface roughness of the glass ceramic fired body. No, the bending strength of the fired body is reduced.

On the other hand, the low-temperature fired substrate described in JP-A-1-203242 has a relative dielectric constant of 3 (1 MHz).
However, the bending strength of the substrate is 1100 kgf / cm ² , and it cannot be said that the substrate has sufficient strength.

Further, in the method for manufacturing a low-temperature fired substrate described in Japanese Patent Application Laid-Open No. 1-308867, a glass ceramic material composed of a mixture of glass powder and mullite powder is used as the substrate material, and the relative dielectric constant of the substrate is 6 or less. Although it is low, the glass material composition contains 40 to 70% by weight of lead oxide, and it is considered that there will be many problems in the production thereof from the viewpoint of protection of global environmental problems.

Further, in the low-temperature fired porcelain composition for a multilayer substrate described in JP-A-1-197359, the relative dielectric constant of the substrate is 6 to 8, and the bending strength is also 1500 kgf /.
cm ² or more and is shown a sufficient value, the firing temperature is 950
It is as high as 1020 ° C., and it is hard to say that it is suitable for simultaneous firing with a silver conductor.

Therefore, in this embodiment, the relative dielectric constant is as low as 6 to 8 with respect to the relative dielectric constant of 10 of the 96% alumina substrate.
With sufficient mechanical strength of 1500 kgf / cm ² and 95
Sufficient sinterability is obtained at 0 ° C. or lower, so that a glass ceramic material that can be co-fired with a conductive material such as silver can be obtained. Further, since the glass material does not contain a lead oxide component, unlike the glass ceramic material composed of a mixture of glass and ceramic powder containing lead oxide which has been widely used in the past, the adverse effect on the environment in the production can be reduced.

The present invention is not limited to the present embodiment. Other constituents in the glass include alkali metal oxides, alkaline earth metal oxides, and Sn as oxides.
O ₂ and P ₂ O ₅ can be exemplified. Further, it goes without saying that the glass material described in the present invention is effective not only as a glass ceramic material for a substrate, but also as a material for overcoating a substrate by making it into a paste.

[0060]

As is apparent from the above description, according to the present invention, a glass which can obtain sufficient wettability with the ceramic at the time of co-firing with the ceramic even at a low temperature, and which has a low dielectric constant and sufficient mechanical strength. In addition, it is possible to obtain a glass-ceramic material having sufficient sinterability even at a low temperature at which simultaneous firing with the conductor material is possible.

[Brief description of the drawings]

FIG. 1 (a) is a characteristic diagram showing the relationship between the average particle size of glass powder, alumina powder, and forsterite powder and the surface roughness of a sintered body of a glass ceramic material in one embodiment of the present invention. Characteristic diagram showing the relationship between the average particle size of the glass powder, alumina powder, and forsterite powder and the bending strength of the glass ceramic material fired body in the same embodiment.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hidenori Katsumura 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. 72) Inventor Ryo Kimura 1006 Kazuma Kadoma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Yoshio Miyahara 2-7-1 Hararashi, Otsu, Shiga Prefecture Nippon Electric Glass Co., Ltd.

Claims (9)

[Claims] 1. SiO ₂ = 40 to 50 by weight.
%, BaO = 30~40%, La 2 O 3 = 7~13%, B
₂ O ₃ = 3 to 8%, Al ₂ O ₃ = 3 to 8%, K ₂ O = 1.5
Glass with a composition of ~ 2.5%. 2. A glass-ceramic material comprising a mixture of the glass powder and the ceramic powder according to claim 1. 3. The glass-ceramic material according to claim 2, wherein the ceramic powder is alumina. 4. The glass-ceramic material according to claim 2, wherein the ceramic powder is forsterite. 5. The glass ceramic material according to claim 3, wherein the content of alumina in 100 parts by weight of the mixture is at least 25 parts by weight and less than 40 parts by weight. 6. The glass-ceramic material according to claim 4, wherein the content of forsterite in 100 parts by weight of the mixture is at least 30 parts by weight and less than 45 parts by weight. 7. The glass-ceramic material according to claim 2, wherein the average particle size of the glass powder is 3.5 μm or less. 8. The glass-ceramic material according to claim 3, wherein the average particle size of the alumina is 2.0 μm or less. 9. The average particle size of forsterite is 2.5 μm.
5. The glass-ceramic material according to claim 4, wherein m is equal to or less than m.