JP2003112965A - Low temperature burned ceramic material, and low temperature burned ceramic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a low temperature burned ceramic substrate to deal with the increase of frequencies, and to impart substrate strength required for securing reliability thereto by increasing its Qf value. SOLUTION: The low temperature burned ceramic material forming green sheets 11a, 11b and 11c is obtained by mixing a 35 to 40 wt.% filler essentially cosisting of Al2 O3 (alumina) and 60 to 65 wt.% SiO2 -CaO-B2 O3 -Al2 O3 based glass powder. The filler contains 0.5 to 2.0 wt.% BaO and 33 to 39.5 wt.% Al2 O3 to the total weight of the low temperature burned ceramic material. The glass powder contains 45 to 55 wt.% SiO2 , 15 to 21 wt.% CaO, 6.5 to 7.7 wt.% B2 O3 , 4.2 to 5.1 wt.% Al2 O3 , 6.4 to 18 wt.% BaO, 1.5 to 2.5 wt.% ZnO, and 2 to 4 wt.% SnO2 with impurities of <=2 wt.%.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to SiO ₂ -CaO.
It relates low-temperature fired ceramic material and the low-temperature fired ceramic substrate including a glass powder -B ₂ O ₃ -Al ₂ O ₃ system.

[0002]

2. Description of the Related Art Conventionally, the most widely used ceramic substrate is an alumina substrate, which has a high dielectric constant and needs to be fired at a high temperature of 1500 ° C. or higher.
It is unavoidable to use a refractory metal having a high resistance value such as Mo or W as a wiring conductor to be co-fired. For this reason, in response to the recent demand for high-speed and high-frequency signal processing, it has become difficult to design a package on an alumina substrate.

Under these circumstances, in recent years, 800 to 10
The demand for low-temperature fired ceramic substrates that can be fired at 00 ° C is rapidly expanding. This low-temperature fired ceramic substrate is used as a wiring conductor that is fired at the same time as Ag, Ag-Pd, Au,
It is possible to use low resistance conductors such as Cu, and has the characteristic that the dielectric constant of ceramics is low and that it can handle high-speed and high-frequency signal processing.

At present, low-temperature fired ceramic materials which have been developed or put into practical use include those having a single composition such as crystallized glass type and non-glass type, but in many cases, glass and aggregate (crystalline filler) are used. It is a glass composite system composed of a mixture. Examples of the glass composite low-temperature fired ceramic material include SiO ₂ —CaO—B ₂ O ₃ —Al ₂ O.
There is a mixture of ₃ type glass powder and Al ₂ O ₃ powder (alumina powder).

[0005]

By the way, there is a Qf value as an index showing the adaptability to high speed / high frequency of signal processing. The higher this Qf value, the easier it is to cope with high speed / high frequency. is there. The above-mentioned conventional glass-composite low-temperature firing ceramic material has a Qf value of about 2000 GHz, but in order to cope with the recent remarkable development of high speed and high frequency, low temperature firing with a high Qf value of 3000 GHz or more. It is necessary to develop new ceramic materials. Further, in order to secure the connection reliability between the low temperature fired ceramic substrate and the chip, it is necessary to secure the mechanical strength such as the bending strength of the low temperature fired ceramic substrate.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a low-temperature fired ceramic material and a low-temperature fired ceramic which have both a higher Qf value and a substrate strength required for ensuring reliability than ever before. To provide a substrate.

[0007]

In order to achieve the above object, the low temperature fired ceramic material according to claim 1 of the present invention is an aggregate mainly composed of Al ₂ O ₃ (alumina): 35
And 40 _{wt%, SiO 2 -CaO-B 2} O 3 -Al 2
O ₃ -based glass powder: a low-temperature fired ceramic material mixed with 60 to 65% by weight, and its aggregate is 0.5 to 2.0 BaO based on the total weight of the low-temperature fired ceramic material.
% By weight, and the glass powder contains 6.4 to 18% by weight of BaO with respect to the total weight of the glass powder. That is, it is characterized in that an appropriate amount of BaO is added to both the aggregate and the glass powder. B
It was prepared by adding the aO BaO-SiO ₂ -CaO-B
_{The 2} O ₃ —Al ₂ O ₃ -based glass powder has a characteristic that the Qf value increases when crystallized in the firing process. Furthermore, when BaO is added to the aggregate, the above-mentioned BaO-Si is added in the firing step.
Crystals of O ₂ —CaO—B ₂ O ₃ —Al ₂ O ₃ type glass are likely to be deposited, and the glass deposition amount tends to increase. As a result, the Qf value of the low temperature fired ceramic material can be increased to 3000 GHz or higher.

In this case, if the amount of BaO added to the aggregate is less than 0.5% by weight, the effect of addition is small and the amount of glass deposited is small. On the contrary, the added amount of BaO in the aggregate is 2.0% by weight.
It has been found from the test results described below that the bending strength decreases when the amount is larger than the above. Therefore, the appropriate range of the amount of BaO added to the aggregate is considered to be 0.5 to 2.0% by weight.

Further, the amount of BaO added to the glass powder is 6.4.
If it is less than wt%, the effect of adding BaO is small and Q
Little improvement in f value. On the contrary, if the amount of BaO added to the glass powder is more than 18% by weight, vitrification becomes difficult. Therefore, the proper range of the amount of BaO added to the glass powder is
It is considered to be 6.4 to 18% by weight.

Further, when the amount of aggregate in the low temperature fired ceramic material is less than 35% by weight (when the glass powder is more than 65% by weight), the aggregate is insufficient and the transverse strength is weakened.
On the other hand, if the amount of aggregate is more than 40% by weight (the amount of glass powder is less than 60% by weight), there is a possibility of insufficient glass and sintering failure. Therefore, the aggregate is
And 0 _{wt%, BaO-SiO 2 -CaO-} B 2 O 3 -
By setting the Al ₂ O ₃ -based glass powder to 60 to 65% by weight, it is possible to secure the bending strength and sinterability that can be practically used.

In this case, as in claim 2, the glass powder contains SiO ₂ : 45 to 5 relative to the total weight of the glass powder.
5 wt%, CaO: 15 to 21 _{wt%, B 2 O 3: 6} .
5 to 7.7 wt%, Al ₂ O _3: 4.2~5.1 wt%, BaO: 6.4~18 wt%, ZnO: 1.5 to
A composition containing 2.5 wt%, SnO ₂ : 2 to 4 wt%, and impurities: 2 wt% or less is preferable. That is,
As a glass raw material, in addition to BaO, an appropriate amount of ZnO and SnO ₂
The added made the _{BaO-SiO 2 -CaO-B 2} O 3
-Al ₂ O ₃ -ZnO-SnO ₂ glass of, ZnO
As compared with the glass to which is not added, the Qf value becomes higher and ZnO plays a role of lowering the melting point of the glass.
In addition, when SnO ₂ is added during the production of glass powder, the melting point of glass can be lowered by 30 to 50 ° C. as compared with the case where SnO ₂ is not added, and the production of glass powder is facilitated. .

In this case, ZnO in the glass powder is 1.5
If it is less than wt%, the melting point of the glass will be 1400 ° C or higher. On the other hand, if ZnO is more than 2.5% by weight, vitrification becomes difficult. Therefore, ZnO
If it is 5 to 2.5% by weight, the glass melting point can be appropriately lowered to facilitate vitrification.

Further, SnO ₂ in the glass powder is 2% by weight.
If the amount is less than the above, the electrical characteristics deteriorate, and SnO
_{When 2} is more than 4% by weight, thermal expansion becomes large. Therefore, when SnO ₂ is ₂ to 4% by weight, the electrical characteristics and thermal expansion characteristics are improved.

Further, CaO in the glass powder is 15% by weight.
If the amount is less than the above, precipitation of nSiO ₂ · CaO · Al ₂ O ₃ -based crystals is reduced, and the required strength cannot be obtained. On the other hand, when CaO is more than 21% by weight, the glass melting point becomes too low. Therefore, if CaO is 15 to 21% by weight, it is possible to obtain a glass having a high strength and an appropriately low glass melting point.

If the SiO ₂ content in the glass powder is less than 45% by weight, nSiO ₂ .CaO system or BaO.
Precipitation of SiO ₂ type crystals is reduced, and required strength cannot be obtained. On the contrary, if the SiO ₂ content is more than 55% by weight, vitrification becomes difficult. Therefore, if SiO ₂ is 45-
When it is 55% by weight, vitrification can be facilitated while ensuring strength.

In general, SiO ₂ , CaO and BaO alone form a glass having a high melting point, so that it is necessary to add B ₂ O ₃ as an additive for lowering the melting point. If the B ₂ O ₃ content in the glass powder is less than 6.5% by weight, it will be 1400.
It becomes difficult to vitrify below ℃. On the contrary, if the B ₂ O ₃ content is more than 7.7% by weight, the required strength cannot be obtained.
Therefore, if the B ₂ O ₃ content is 6.5 to 7.7% by weight, it is possible to secure the required strength while appropriately lowering the glass melting point.

Further, Al ₂ O ₃ in the glass powder plays a role of lowering the melting point of the glass, so Al ₂ O ₃ is 4.
If it is less than 2% by weight, the melting point of glass will be 1400 ° C. or higher. On the contrary, Al ₂ O ₃ is 5.1% by weight
If it is more than that, vitrification becomes difficult. Therefore, Al ₂
When O ₃ is 4.2 to 5.1% by weight, the glass melting point can be appropriately lowered to facilitate vitrification.

Further, as described in claim 3, the aggregate of the low temperature fired ceramic material preferably contains 33 to 39.5% by weight of Al ₂ O ₃ with respect to the total weight of the low temperature fired ceramic material. That is, if the Al ₂ O ₃ content is less than 33% by weight, the bending strength becomes weak, and conversely, the Al ₂ O ₃ content is ₃ % or less.
If it is more than 9.5% by weight, sintering failure will occur. Therefore, if the Al ₂ O ₃ content is 33 to 39.5% by weight, it is possible to secure the bending strength and sinterability that can withstand practical use.

Further, as described in claim 4, it is preferable that the low temperature fired ceramic substrate is manufactured by firing the ceramic raw substrate formed by using the low temperature fired ceramic material having the above composition at 800 to 1000 ° C. As a result, it is possible to manufacture a high-quality low-temperature fired ceramic substrate having both a high Qf value capable of coping with the recent increase in speed and frequency and a substrate strength necessary for ensuring reliability.

In this case, as in claim 5, the composition of the low temperature fired ceramic substrate is as follows: SiO ₂ : 27 to 35.8 wt%, CaO: 9 to 13.7 wt%, B ₂ O ₃ : 3.9. ~
5 wt%, Al ₂ O _3: 36~42.8 wt%, Ba
O: It is good to set it as 4.3-13.7 weight%. The composition of the low temperature fired ceramic substrate is a specific example of the composition of the low temperature fired ceramic substrate when the low temperature fired ceramic substrate is formed by using the low temperature fired ceramic material according to claim 1, and the addition amount of BaO (4. 3 to 13.7% by weight) corresponds to the total addition amount of BaO added to both the aggregate and the glass powder of claim 1. By adding this BaO,
The Qf value of the low temperature fired ceramic substrate can be increased to 3000 GHz or more.

Further, according to claim 6, the low temperature fired ceramic substrate having the above composition contains ZnO: 0.9 to 1.6 wt% and SnO ₂ : 1.2 to 2.6 wt%. Good to do. The composition of this low temperature fired ceramic substrate is
It corresponds to the composition of the low temperature fired ceramic substrate when the low temperature fired ceramic substrate is formed using the low temperature fired ceramic material according to claim 2. Thus, by adding an appropriate amount of ZnO and SnO ₂ to the low temperature fired ceramic substrate,
The Qf value of the low temperature fired ceramic substrate can be further increased and the substrate strength can be increased.

Further, as in claim 7, the low temperature fired ceramic substrate of the above composition and the wiring conductor of the low melting point metal may be fired at the same time. As a result, a high Qf having a wiring conductor with low resistance and excellent electrical characteristics in the inner layer or surface layer of the substrate
Value low temperature fired ceramic substrates can be manufactured in a single firing step.

In the above-described claims 1 to 7, a suitable amount of B is added to both the aggregate of the low temperature fired ceramic material and the glass powder.
Although aO is added, as in claim 8, BaO may be added only to the aggregate of the low temperature fired ceramic material, and SrO may be added to the glass powder instead of BaO.

The low temperature fired ceramic material according to claim 8 is an aggregate mainly composed of Al ₂ O ₃ (alumina): 35
And 40 _{wt%, SiO 2 -CaO-B 2} O 3 -Al 2
O ₃ -based glass powder: a low-temperature fired ceramic material mixed with 60 to 65% by weight, and its aggregate is 0.5 to 2.0 BaO based on the total weight of the low-temperature fired ceramic material.
% By weight, and the glass powder contains 11 to 18.8% by weight of SrO with respect to the total weight of the glass powder. SrO—SiO ₂ —CaO—B ₂ O ₃ —Al ₂ produced by adding SrO in this way
The O ₃ -based glass powder has a characteristic that when it is crystallized in the firing step, the bending strength is increased. Further, when BaO is added to the aggregate, crystals of BaO—SrO—SiO ₂ type glass are likely to precipitate in the firing step, and the amount of glass deposition tends to increase. As a result, the Qf value of the low temperature fired ceramic material can be increased to 3000 GHz or higher.

In this case, if the amount of BaO added to the aggregate is less than 0.5% by weight, the effect of addition is small and the amount of glass deposited is small. On the contrary, the added amount of BaO in the aggregate is 2.0% by weight.
It has been found from the test results described below that the bending strength decreases when the amount is larger than the above. Therefore, the appropriate range of the amount of BaO added to the aggregate is considered to be 0.5 to 2.0% by weight.

When the amount of SrO added to the glass powder is less than 11% by weight, the effect of adding SrO is small and the bending strength is not improved so much. On the contrary, if the amount of SrO added to the glass powder is more than 18.8% by weight, vitrification becomes difficult. Therefore, the proper range of the SrO addition amount of the glass powder is considered to be 11 to 18.8 wt%.

If the amount of the aggregate in the low temperature fired ceramic material is less than 35% by weight (the amount of glass powder is more than 65% by weight), the aggregate is insufficient and the flexural strength becomes weak.
On the other hand, if the amount of aggregate is more than 40% by weight (the amount of glass powder is less than 60% by weight), there is a possibility of insufficient glass and sintering failure. Therefore, the aggregate is
And 0 _{wt%, SrO-SiO 2 -CaO-} B 2 O 3 -
By setting the Al ₂ O ₃ -based glass powder to 60 to 65% by weight, it is possible to secure the bending strength and sinterability that can be practically used.

In this case, as in claim 9, the glass powder contains SiO ₂ : 47 to 5 relative to the total weight of the glass powder.
5% by weight, CaO: 10 to 14.4% by weight, B ₂ O ₃ :
6.5-7.2 wt%, Al ₂ O ₃ : 4.2-5.0 wt%, SrO: 11-18.8 wt%, ZnO: 4.5
˜5.5 wt%, SnO ₂ : 2.0 to 4.3 wt%, and impurities: 2 wt% or less is preferable. That is, in addition to SrO, an appropriate amount of Zn is used as the glass raw material.
O and SrO-SiO ₂ -Ca the SnO ₂ was prepared by adding
The O—B ₂ O ₃ —Al ₂ O ₃ —ZnO—SnO ₂ based glass has a higher Qf value and ZnO serves to lower the melting point of the glass, as compared with glass to which ZnO is not added. In addition, when manufacturing glass powder, SnO
_{When 2} is added, the melting point of glass can be lowered by 30 to 50 ° C. as compared with the case where SnO ₂ is not added, and the production of glass powder becomes easy.

In this case, the ZnO content in the glass powder is 4.5.
If it is less than wt%, the melting point of the glass will be 1400 ° C or higher. On the contrary, when ZnO is more than 5.5% by weight, it becomes difficult to vitrify. Therefore, ZnO is 4.
When it is 5 to 5.5% by weight, the glass melting point can be appropriately lowered to facilitate vitrification.

Further, SnO ₂ in the glass powder is 2% by weight.
If the amount is less than the above, the electrical characteristics deteriorate, and SnO
_{When 2} is more than 4.3% by weight, thermal expansion becomes large.
Therefore, when SnO ₂ is ₂ to 4.3% by weight, the electrical characteristics and the thermal expansion characteristics are improved.

Further, CaO in the glass powder is 10% by weight.
If the amount is less than the above, precipitation of nSiO ₂ · CaO · Al ₂ O ₃ -based crystals is reduced, and the required strength cannot be obtained. On the contrary, when CaO is more than 14.4% by weight, the glass melting point becomes too low. Therefore, CaO is 10 to 14.4.
When the content is wt%, it is possible to obtain a glass having a high strength and an appropriately low melting point.

When the SiO ₂ content in the glass powder is less than 47% by weight, nSiO ₂ .CaO system or SrO.
Precipitation of SiO ₂ type crystals is reduced, and required strength cannot be obtained. On the contrary, if the SiO ₂ content is more than 55% by weight, vitrification becomes difficult. Therefore, the SiO ₂ is 47-
When it is 55% by weight, vitrification can be facilitated while ensuring strength.

Generally, only SiO ₂ , CaO and SrO form a glass having a high melting point, so that it is necessary to add B ₂ O ₃ as an additive for lowering the melting point. If the B ₂ O ₃ content in the glass powder is less than 6.5% by weight, it will be 1400.
It becomes difficult to vitrify below ℃. On the contrary, if the B ₂ O ₃ content is more than 7.2% by weight, the required strength cannot be obtained.
Therefore, if the B ₂ O ₃ content is 6.5 to 7.2% by weight, it is possible to secure the necessary strength while appropriately lowering the glass melting point.

Further, Al ₂ O ₃ in the glass powder plays a role of lowering the melting point of glass, so Al ₂ O ₃ is 4.
If it is less than 2% by weight, the melting point of glass will be 1400 ° C. or higher. On the contrary, Al ₂ O ₃ is 5.0% by weight
If it is more than that, vitrification becomes difficult. Therefore, Al ₂
When O ₃ is 4.2 to 5.0% by weight, the glass melting point can be appropriately lowered to facilitate vitrification.

In the tenth aspect, the aggregate of the low temperature fired ceramic material may contain 33 to 39.5 wt% of Al ₂ O ₃ with respect to the total weight of the low temperature fired ceramic material. That is, if the Al ₂ O ₃ content is less than 33% by weight, the bending strength becomes weak, and conversely, if the Al ₂ O ₃ content is more than 39.5% by weight, defective sintering occurs. Therefore, if the Al ₂ O ₃ content is 33 to 39.5% by weight, it is possible to secure the bending strength and sinterability that can withstand practical use.

Further, as described in claim 11, it is preferable to manufacture a low temperature fired ceramic substrate by firing a ceramic raw substrate formed by using the low temperature fired ceramic material having the above composition at 800 to 1000 ° C. As a result, it is possible to manufacture a high-quality low-temperature fired ceramic substrate having both a high Qf value capable of coping with the recent increase in speed and frequency and a substrate strength necessary for ensuring reliability.

In this case, as in claim 12, the composition of the low temperature fired ceramic substrate is SiO ₂ : 28.2 to 35.
8% by weight, CaO: 6.0 to 9.4% by weight, BaO:
0.5-2.0 wt%, B ₂ O _3: 3.9~4.7 wt%, Al ₂ O _3: 32.5~42.8 wt%, SrO:
It is good to set it as 6.6 to 12.2% by weight. The composition of the low temperature fired ceramic substrate is a specific example of the composition of the low temperature fired ceramic substrate when the low temperature fired ceramic substrate is formed using the low temperature fired ceramic substrate according to claim 8.
By adding BaO, the Qf value of the low temperature fired ceramic substrate can be increased to 3000 GHz or more, and Sr
The addition of O can increase the bending strength of the low temperature fired ceramic substrate.

Further, as in claim 13, the low temperature fired ceramic substrate having the above composition contains ZnO: 2.7 to 3.6% by weight and SnO ₂ : 1.2 to 2.8% by weight. Good to do. The composition of this low temperature fired ceramic substrate is
It corresponds to the composition of the low temperature fired ceramic substrate when the low temperature fired ceramic substrate is formed using the low temperature fired ceramic material according to claim 9. Thus, by adding an appropriate amount of ZnO and SnO ₂ to the low temperature fired ceramic substrate,
The Qf value of the low temperature fired ceramic substrate can be further increased and the substrate strength can be increased.

Further, as in claim 14, the low temperature fired ceramic substrate having the above composition and the wiring conductor of the low melting point metal may be fired simultaneously. As a result, a high Q having a wiring conductor with low resistance and excellent electrical characteristics in the inner layer or surface layer of the substrate
A low-temperature fired ceramic substrate having an f value can be manufactured in a single firing process.

[0040]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment (1)] An embodiment (1) of the present invention will be described below with reference to FIG. The low temperature fired ceramic multilayer substrate is formed by laminating a plurality of green sheets 11a, 11b and 11c formed of a low temperature fired ceramic material and firing them at 800 to 1000 ° C. In this case, the low temperature fired ceramic material is an aggregate containing Al ₂ O ₃ (alumina) as a main component: 35 to 40 wt% and SiO 2.
_{2 -CaO-B 2 O 3 -Al} 2 O 3 based glass powder: 6
A mixture of 0 to 65% by weight is used.

The aggregate of the low temperature fired ceramic material has a BaO: 0.5 to 0.5 based on the total weight of the low temperature fired ceramic material.
2.0 wt% and Al ₂ O _3: 33~39.5 contains a weight%.

The glass powder contains SiO ₂ : 45 to 55% by weight and CaO: 15 to 21 with respect to the total weight of the glass powder.
Wt%, B ₂ O _3: 6.5~7.7 wt%, Al
₂ O ₃ : 4.2 to 5.1% by weight, BaO: 6.4 to 18
% By weight, ZnO: 1.5 to 2.5% by weight, SnO ₂ : 2
~ 4 wt%, impurities: BaO-containing less than 2 wt%
_{SiO 2 -CaO-B 2 O 3} -Al 2 O 3 -ZnO-S
nO ₂ type glass powder is used.

Green sheets 11a, 11b, 11c
Is prepared by mixing a low temperature fired ceramic material having the above composition with a binder (eg acrylic resin, butyral resin), a solvent (eg toluene, xylene, butanol) and a plasticizer and thoroughly stirring and mixing to prepare a slurry. The slurry is tape-formed by a doctor blade method or the like.

Green sheets 11a, 11b, 1 of each layer
Before stacking 1c, the green sheets 11a, 1 of each layer are stacked.
A via conductor 13 is filled in the via hole 12 punched in 1b. The via conductor 13 of each layer is, for example, A
It is formed by printing an Ag-based conductor paste mainly containing g, Ag / Pd, Ag / Pt, Ag / Au and the like. still,
The via conductor 13 of each layer is replaced with Ag-based conductor paste,
A paste of a low melting point metal such as Au or Cu may be used. Further, the green sheets 11b and 11c of the second layer and below
The inner layer wiring conductor 14 is screen-printed using a conductor paste of the same low melting point metal as that of the via conductor 13.

On the first layer (top layer) of the green sheet 11a, the surface wiring conductors 1 such as pads and wiring patterns are provided.
5 is screen-printed using the above-mentioned low-melting-point metal conductor paste such as Ag-based, Au-based, and Cu-based. The surface wiring conductor 15 may be printed and fired after the substrate is fired.

After the printing process, the green sheet 11 of each layer
A, 11b, and 11c are laminated, thermocompression-bonded, and integrated to produce a low temperature fired ceramic green substrate. Then, this low-temperature fired ceramic green substrate is fired at 800 to 1000 ° C. (preferably 900 ° C. or less) to simultaneously form the green sheets 11a, 11b and 11c of each layer, the via conductor 13, the inner layer wiring conductor 14 and the surface layer wiring conductor 15. Firing is performed to manufacture a low temperature firing ceramic multilayer substrate.

The composition of the low temperature fired ceramic multilayer substrate after firing is as follows: SiO ₂ : 27-35.8 wt%, CaO: 9-
13.7 wt%, B ₂ O ₃ : 3.9-5 wt%, Al ₂
O _3: 36~42.8 weight%, BaO: 4.3~13.
7% by weight, ZnO: 0.9 to 1.6% by weight, SnO ₂ :
It is 1.2 to 2.6% by weight.

In this embodiment (1) described above, an appropriate amount of Ba is used for both the glass powder and the aggregate of the low temperature fired ceramic material forming the green sheets 11a, 11b, 11c.
It is characterized by the addition of O, and further characterized by the addition of appropriate amounts of ZnO and SnO ₂ to the glass powder.

The glass powder to which BaO is added has a characteristic of increasing the Qf value when crystallized in the firing process. Furthermore,
If an appropriate amount of BaO is added to the aggregate, BaO
Crystals of the —SiO ₂ —CaO—B ₂ O ₃ —Al ₂ O ₃ type glass tend to precipitate, and the amount of glass precipitation tends to increase. As a result, the Q of the low temperature fired ceramic material is
It is possible to increase the f value to 3000 GHz or higher.

In addition to BaO, an appropriate amount of ZnO and SnO ₂ was added to the glass raw material to form BaO-SiO _{2
-CaO-B 2 O 3 -Al 2} O 3 -ZnO-SnO 2 system glass, as compared to glass without the addition of ZnO, Q
As the f value increases, ZnO plays a role of lowering the melting point of glass. Also, when manufacturing glass powder,
When SnO ₂ is added, the melting point of glass can be lowered by 30 to 50 ° C. as compared with the case where SnO ₂ is not added, and the production of glass powder becomes easy.

[0051]

EXAMPLES The present inventor has found that the composition of the glass powder and the B of the aggregate
A test was conducted to evaluate the appropriate range of the amount of aO added and the compounding ratio of the glass powder and the aggregate. The test results are shown in Tables 1 and 2 below.

[0052]

[Table 1]

[0053]

[Table 2]

In this evaluation test, glass powders having four compositions shown in Table 1 were prepared. In the method for producing this glass powder, the mixture having the composition shown in Table 1 was melted, vitrified and rapidly cooled, and this was crushed to produce glass powder having an average particle size of about 10 μm.

The aggregates used in this test were aggregates containing only Al ₂ O ₃ with no addition of BaO, and 0.5% by weight, 1.0% by weight, and 1% by weight of BaO with respect to the total weight of the low temperature fired ceramic material. Aggregates of 0.5% by weight, 2.0% by weight and 3.0% by weight were used.

Then, the glass powder and the aggregate were mixed at the compounding ratio shown in Table 2 to prepare a low temperature fired ceramic material, and a solvent, an acrylic resin (binder) and a plasticizer were added to the low temperature fired ceramic material. The mixture was blended and sufficiently stirred and mixed to prepare a slurry, which was tape-formed by a doctor blade method and dried to prepare a green sheet having a thickness of 0.1 mm.

After that, 12 green sheets were laminated and thermocompression bonded, and then this was 10.0 mm × 50.0 mm.
A sample substrate was prepared by cutting into a size of. And
This sample substrate was fired in the air under the conditions of 900 ° C. and hold for 30 minutes, and the quality of sintering was evaluated. Further, with respect to the sintered sample substrate, the bending strength of the sample substrate was measured by a bending test. As a result, as shown in Table 2, measured values of sinterability and bending strength of 17 types of samples # 1 to # 17 were obtained.

On the other hand, the Qf value of each of the samples # 1 to # 17 was measured as follows. Each sample # 1 to # 1
A low-temperature fired ceramic material having the composition of 7 was molded into a cylindrical shape having a diameter of 15 mm by a die press to prepare a sample, and the sample was fired in the air at 930 ° C. for 30 minutes hold. Then, using the sintered sample, the Q value and the resonance frequency f were measured by the dielectric resonance method, and the Qf value was calculated. This Qf value is an index showing the adaptability to speeding up / frequency increasing the signal processing, and the higher the Qf value, the easier it is to cope with speeding up / frequency increasing. The conventional glass composite low temperature firing ceramic material has a Qf value of 2000G.
Although it is in the order of Hz, the recent speeding up that has made remarkable progress
In order to handle higher frequencies, it is preferable to have a high Qf value of 3000 GHz or higher.

The acceptance criteria in this evaluation test are good sinterability, flexural strength of 170 MPa or more, and
The Qf value was 3000 GHz or more, and when all of these three conditions were satisfied, it was evaluated as pass (◯), and when any one of them was not satisfied, it was evaluated as fail (x).

Samples # 1 and # 2 using the glass powder having the composition shown in Table 1 both failed (x). In addition, samples # 3 to # using the glass powder of composition
In No. 17, the evaluation was divided into pass (◯) and fail (x) depending on the amount of BaO added to the aggregate and the compounding ratio of the glass powder and the aggregate.

From this fact, it was found that the composition of the glass powder is appropriate within the range of to in Table 1. The composition of the glass powder - in Table 1, with respect to the glass powder to the total weight, SiO _2: 45 to 55 wt%, Ca
O: 15 to 21 wt%, B ₂ O _3: 6.5~7.7 wt%, Al ₂ O _3: 4.2~5.1 wt%, BaO: 6.
4-18 wt%, ZnO: 1.5-2.5 wt%, Sn
O ₂ : Within the range of 2 to 4% by weight.

In this case, if the amount of BaO added to the glass powder is less than 6.4% by weight, the effect of adding BaO is small and the improvement of the Qf value is small. On the contrary, B of glass powder
If the amount of aO added is more than 18% by weight, vitrification becomes difficult. Therefore, the appropriate range of the amount of BaO added to the glass powder is considered to be 6.4 to 18% by weight.

ZnO in the glass powder plays a role of raising the Qf value and lowering the melting point of the glass. If the ZnO content in the glass powder is less than 1.5% by weight, the melting point of the glass will be 1400 ° C. or higher. On the other hand, if ZnO is more than 2.5% by weight, vitrification becomes difficult. Therefore, if ZnO is 1.5 to 2.5% by weight, the glass melting point can be appropriately lowered to facilitate vitrification.

Further, SnO ₂ in the glass powder is 2% by weight.
If the amount is less than the above, the electrical characteristics deteriorate, and SnO
_{When 2} is more than 4% by weight, thermal expansion becomes large. Therefore, when SnO ₂ is ₂ to 4% by weight, the electrical characteristics and thermal expansion characteristics are improved.

Further, CaO in the glass powder is 15% by weight.
If the amount is less than the above, precipitation of nSiO ₂ · CaO · Al ₂ O ₃ -based crystals is reduced, and the required strength cannot be obtained. On the other hand, when CaO is more than 21% by weight, the glass melting point becomes too low. Therefore, if CaO is 15 to 21% by weight, it is possible to obtain a glass having a high strength and an appropriately low glass melting point.

If the SiO ₂ content in the glass powder is less than 45% by weight, nSiO ₂ .CaO system or BaO.
Precipitation of SiO ₂ type crystals is reduced, and required strength cannot be obtained. On the contrary, if the SiO ₂ content is more than 55% by weight, vitrification becomes difficult. Therefore, if SiO ₂ is 45-
When it is 55% by weight, vitrification can be facilitated while ensuring strength.

In general, SiO ₂ , CaO and BaO alone form a glass having a high melting point, so that B ₂ O ₃ must be added as an additive for lowering the melting point. If the B ₂ O ₃ content in the glass powder is less than 6.5% by weight, it will be 1400.
It becomes difficult to vitrify below ℃. On the contrary, if the B ₂ O ₃ content is more than 7.7% by weight, the required strength cannot be obtained.
Therefore, if the B ₂ O ₃ content is 6.5 to 7.7% by weight, it is possible to secure the required strength while appropriately lowering the glass melting point.

Further, Al ₂ O ₃ in the glass powder plays a role of lowering the melting point of glass, so Al ₂ O ₃ is 4.
If it is less than 2% by weight, the melting point of glass will be 1400 ° C. or higher. On the contrary, Al ₂ O ₃ is 5.1% by weight
If it is more than that, vitrification becomes difficult. Therefore, Al ₂
When O ₃ is 4.2 to 5.1% by weight, the glass melting point can be appropriately lowered to facilitate vitrification.

Next, an appropriate range of the amount of BaO added to the aggregate will be considered. The sample using the aggregate of Al ₂ O ₃ only, which did not contain BaO, had a Qf value of less than 3000 GHz or had poor sintering, and was evaluated as rejected (x). In addition, the samples with 0.5% by weight, 1.0% by weight, and 2.0% by weight of BaO added to the aggregate all have a Qf value of 3000 GHz.
As described above, the sinterability was good, and the transverse rupture strength was 170 MPa or more, and it was evaluated as acceptable (◯). However, sample # 7 having an added amount of BaO in the aggregate of 3.0% by weight had a flexural strength of 16%.
It decreased to 5 MPa and did not satisfy the acceptance criteria (170 MPa or more), and was evaluated as a failure (x). From this, it is considered that the appropriate range of the amount of BaO added to the aggregate is 0.5 to 2.0% by weight.

Next, an appropriate range of the compounding ratio of glass powder and aggregate will be considered. In this test, the compounding ratio of glass powder was 5
The content was set to 5 to 70% by weight and the aggregate to 30 to 45% by weight.
The samples of glass powder: 55% by weight and aggregate: 45% by weight were all evaluated to be unacceptable (x) because of insufficient glass and poor sintering. Further, the samples of glass powder: 70% by weight and aggregate: 30% by weight did not satisfy the acceptance criteria (170 MPa or more) because the aggregate strength was insufficient and the flexural strength decreased to 150 MPa or less. It was evaluated as passing (x).

On the other hand, when the glass powder is 60 to 65% by weight and the aggregate is 35 to 40% by weight, the sample in which the amount of BaO added to the aggregate is in the proper range (0.5 to 2.0% by weight) About the acceptance criteria (sinterability: good, bending strength> 170M
The condition of Pa, Qf value> 3000 GHz) was satisfied, and it was evaluated as pass (◯). From this, the appropriate range of the mixing ratio of the glass powder and the aggregate is as follows: glass powder: 60 to 65% by weight,
Aggregate: considered to be 35-40% by weight.

[Embodiment (2)] In the embodiment (1), an appropriate amount of BaO is added to both the aggregate of the low temperature fired ceramic material and the glass powder, but in the embodiment (2) described below , B only for aggregate of low temperature fired ceramic material
aO was added, and the glass powder contained Sr instead of BaO.
O was added, and the compounding ratio of each component of the glass powder was adjusted accordingly.

Also in this embodiment (2), the low temperature fired ceramic material for forming the green sheet is Al ₂ O ₃
An aggregate containing (alumina) as a main component: 35 to 40 wt% and a mixture of SiO ₂ —CaO—B ₂ O ₃ —Al ₂ O ₃ -based glass powder: 60 to 65 wt% are used.

The aggregate of the low temperature fired ceramic material has a BaO: 0.5 to 0.5 based on the total weight of the low temperature fired ceramic material.
2.0 wt% and Al ₂ O _3: 33~39.5 contains a weight%.

The glass powder contains SiO ₂ : 47 to 55% by weight and CaO: 10 to 1 with respect to the total weight of the glass powder.
4.4 wt%, B ₂ O _3: 6.5~7.2 wt%, Al
₂ O ₃ : 4.2 to 5.0% by weight, SrO: 11 to 18.
8% by weight, ZnO: 4.5 to 5.5% by weight, SnO ₂ :
SrO—SiO ₂ —CaO—B ₂ O ₃ —Al ₂ O ₃ — containing 2.0 to 4.3 wt% and impurities: 2 wt% or less
A glass powder of ZnO-SnO ₂ system.

Using the slurry of the low-temperature fired ceramic material having this composition, a green sheet is formed by the same method as in the above embodiment (1), and the conductor pattern printing, green sheet lamination and firing steps are performed in this order. A low temperature fired ceramic multilayer substrate is manufactured.

The composition of the low temperature fired ceramic multilayer substrate after firing was SiO ₂ : 28.2 to 35.8% by weight, CaO:
6.0 to 9.4 wt%, BaO: 0.5 to 2.0 wt%, B ₂ O _3: 3.9~4.7 wt%, Al ₂ O _{3: 3}
2.5 to 42.8 wt%, SrO: 6.6 to 12.2 wt%, ZnO: 2.7 to 3.6 wt%, SnO ₂ : 1.
It is 2 to 2.8% by weight.

The present embodiment (2) described above is characterized in that BaO is added only to the aggregate of the low temperature fired ceramic material forming the green sheet, and SrO is added to the glass powder instead of BaO. It is also characterized in that appropriate amounts of ZnO and SnO ₂ are added to the glass powder.

The glass powder to which SrO is added has the property of increasing the bending strength when crystallized in the firing process. Furthermore, if an appropriate amount of BaO is added to the aggregate, B
Crystals of aO—SrO—SiO ₂ type glass tend to be deposited easily, and the amount of deposited glass tends to increase. As a result, the Qf value of the low temperature fired ceramic material is 3000 GH
It is possible to increase it to z or more.

In addition to SrO, an appropriate amount of ZnO and SnO ₂ was added to the glass raw material to prepare SrO-SiO _{2
-CaO-B 2 O 3 -Al 2} O 3 -ZnO-SnO 2 system glass, as compared to glass without the addition of ZnO, Q
As the f value increases, ZnO plays a role of lowering the melting point of glass. Also, when manufacturing glass powder,
When SnO ₂ is added, the melting point of glass can be lowered by 30 to 50 ° C. as compared with the case where SnO ₂ is not added, and the production of glass powder becomes easy.

[0081]

EXAMPLE Regarding the low temperature fired ceramic material having the composition of the present embodiment (2), the present inventor also found that the composition of the glass powder was
A test was conducted to evaluate the proper range of the amount of BaO added to the aggregate and the mixing ratio of the glass powder and the aggregate. The test results are shown in Tables 3 and 4 below.

[0082]

[Table 3]

[0083]

[Table 4]

In this evaluation test, glass powders having four compositions shown in Table 3 were prepared. In the method for producing the glass powder, the mixture having the composition shown in Table 3 was melted, vitrified, and rapidly cooled, and this was crushed to produce glass powder having an average particle diameter of about 10 μm.

The aggregates used in this test were the aggregates containing only Al ₂ O ₃ with no BaO added, and the addition amounts of BaO to the total weight of the low temperature fired ceramic materials were 0.5% by weight, 1.0% by weight, and 1% by weight, respectively. Aggregates of 0.5% by weight, 2.0% by weight and 3.0% by weight were used.

Then, these glass powders and aggregates were mixed at a compounding ratio shown in Table 4 to prepare a low temperature fired ceramic material, and a solvent, an acrylic resin (binder) and a plasticizer were added to the low temperature fired ceramic material. The mixture was blended and sufficiently stirred and mixed to prepare a slurry, which was tape-formed by a doctor blade method and dried to prepare a green sheet having a thickness of 0.1 mm.

After that, 12 sheets of this green sheet were laminated and thermocompression bonded, and then this was 10.0 mm × 50.0 mm.
A sample substrate was prepared by cutting into a size of. And
This sample substrate was fired in the air under the conditions of 900 ° C. and hold for 30 minutes, and the quality of sintering was evaluated. Further, with respect to the sintered sample substrate, the bending strength of the sample substrate was measured by a bending test. As a result, as shown in Table 4, measured values of sinterability and bending strength of 17 types of samples # 21 to # 37 were obtained. Each sample # 21 to # 3
The method of measuring the Qf value of No. 7 is the same as that of the above embodiment (1).

The acceptance criteria in this evaluation test are good sinterability, bending strength of 200 MPa or more, and
The Qf value was 3000 GHz or more, and when all of these three conditions were satisfied, it was evaluated as pass (◯), and when any one of them was not satisfied, it was evaluated as fail (x).

Samples # 21 and # 22 using the glass powder having the composition shown in Table 3 both failed (x). Sample # using glass powder of composition #
Nos. 23 to # 37 were evaluated as pass (◯) and fail (x) depending on the amount of BaO added to the aggregate and the compounding ratio of the glass powder and the aggregate.

From this fact, it was found that the composition of the glass powder within the range from to in Table 3 was appropriate. The composition of the glass powder in Table 3 is as follows: SiO ₂ : 47 to 55% by weight, CaO: based on the total weight of the glass powder.
10 to 14.4 wt%, B ₂ O _3: 6.5~7.2 wt%, Al ₂ O _3: 4.2~5.0 wt%, SrO: 11
˜18.8% by weight, ZnO: 4.5 to 5.5% by weight, S
nO ₂ : Within the range of _{2 to} 4.3% by weight.

In this case, the amount of SrO added to the glass powder was 1
If it is less than 1% by weight, the effect of adding SrO is small,
Little increase in bending strength. On the contrary, Sr of glass powder
If the amount of O added is more than 18.8% by weight, vitrification becomes difficult. Therefore, the proper range of the SrO addition amount of the glass powder is considered to be 11 to 18.8 wt%.

Further, ZnO in the glass powder plays a role of raising the Qf value and lowering the melting point of the glass. If the ZnO content in the glass powder is less than 4.5% by weight, the melting point of the glass will be 1400 ° C. or higher. On the contrary, when ZnO is more than 5.5% by weight, it becomes difficult to vitrify. Therefore, if ZnO is 4.5 to 5.5% by weight, the glass melting point can be appropriately lowered to facilitate vitrification.

Further, SnO ₂ in the glass powder is 2% by weight.
If the amount is less than the above, the electrical characteristics deteriorate, and SnO
_{When 2} is more than 4.3% by weight, thermal expansion becomes large.
Therefore, when SnO ₂ is ₂ to 4.3% by weight, the electrical characteristics and the thermal expansion characteristics are improved.

Further, CaO in the glass powder is 10% by weight.
If the amount is less than the above, precipitation of nSiO ₂ · CaO · Al ₂ O ₃ -based crystals is reduced, and the required strength cannot be obtained. On the contrary, when CaO is more than 14.4% by weight, the glass melting point becomes too low. Therefore, CaO is 10 to 14.4.
When the content is wt%, it is possible to obtain a glass having a high strength and an appropriately low melting point.

When the SiO ₂ content in the glass powder is less than 47% by weight, nSiO ₂ .CaO system or SrO.
Precipitation of SiO ₂ type crystals is reduced, and required strength cannot be obtained. On the contrary, if the SiO ₂ content is more than 55% by weight, vitrification becomes difficult. Therefore, the SiO ₂ is 47-
When it is 55% by weight, vitrification can be facilitated while ensuring strength.

Generally, only SiO ₂ , CaO and SrO form a glass having a high melting point, so that it is necessary to add B ₂ O ₃ as an additive for lowering the melting point. If the B ₂ O ₃ content in the glass powder is less than 6.5% by weight, it will be 1400.
It becomes difficult to vitrify below ℃. On the contrary, if the B ₂ O ₃ content is more than 7.2% by weight, the required strength cannot be obtained.
Therefore, if the B ₂ O ₃ content is 6.5 to 7.2% by weight, it is possible to secure the necessary strength while appropriately lowering the glass melting point.

Further, since Al ₂ O ₃ in the glass powder plays a role of lowering the melting point of the glass, Al ₂ O ₃ is 4.
If it is less than 2% by weight, the melting point of glass will be 1400 ° C. or higher. On the contrary, Al ₂ O ₃ is 5.0% by weight
If it is more than that, vitrification becomes difficult. Therefore, Al ₂
When O ₃ is 4.2 to 5.0% by weight, the glass melting point can be appropriately lowered to facilitate vitrification.

Next, an appropriate range of the amount of BaO added to the aggregate will be considered. The sample using the aggregate of Al ₂ O ₃ only, which did not contain BaO, had a Qf value of less than 3000 GHz or had poor sintering, and was evaluated as rejected (x). In addition, the samples with 0.5% by weight, 1.0% by weight, and 2.0% by weight of BaO added to the aggregate all have a Qf value of 3000 GHz.
As described above, the sinterability was good, and the transverse rupture strength was 200 MPa or more, and it was evaluated as acceptable (◯). However, the bending strength of the sample # 27 containing 3.0% by weight of BaO in the aggregate is 1
It decreased to 70 MPa and did not satisfy the acceptance criteria (200 MPa or more), and was evaluated as unacceptable (x). From this, the proper range of the amount of BaO added to the aggregate is 0.5 to 2.0% by weight.
it is conceivable that.

Next, an appropriate range of the compounding ratio of glass powder and aggregate will be considered. In this test, the compounding ratio of glass powder was 5
The content was set to 5 to 70% by weight and the aggregate to 30 to 45% by weight.
The samples of glass powder: 55% by weight and aggregate: 45% by weight were all evaluated to be unacceptable (x) because of insufficient glass and poor sintering. Further, the samples of glass powder: 70% by weight and aggregate: 30% by weight did not satisfy the acceptance standard (200 MPa or more) because the aggregate strength was insufficient and the transverse strength decreased to 150 MPa or less. It was evaluated as passing (x).

On the other hand, when the glass powder is 60 to 65% by weight and the aggregate is 35 to 40% by weight, the sample in which the amount of BaO added to the aggregate is in the proper range (0.5 to 2.0% by weight) About the acceptance criteria (sinterability: good, bending strength> 200M
The condition of Pa, Qf value> 3000 GHz) was satisfied, and it was evaluated as pass (◯). From this, the appropriate range of the mixing ratio of the glass powder and the aggregate is as follows: glass powder: 60 to 65% by weight,
Aggregate: considered to be 35-40% by weight.

[0101]

As is apparent from the above description, since the low temperature fired ceramic material according to claim 1 of the present invention has an appropriate amount of BaO added to both the aggregate and the glass powder, the Qf of the low temperature fired ceramic material is The value can be increased to 3000 GHz or more, and it is possible to cope with the recent rapid development of high speed and high frequency, and also to provide the mechanical strength necessary for ensuring the reliability of the substrate.

Further, in claim 2, the glass raw material is Ba
In addition to O, appropriate amounts of ZnO and SnO ₂ were added, so Q
The f value can be further increased and the melting point of glass can be lowered, which facilitates the production of glass powder.

Further, in claim 3, the content of Al ₂ O _{3 in the} aggregate is 33 to 33% by weight based on the total weight of the low temperature fired ceramic material.
Since the content is 39.5% by weight, it is possible to secure the bending strength and sinterability that can be practically used.

Further, according to the present invention, the low temperature fired ceramic substrate is manufactured by firing the ceramic raw substrate formed by using the low temperature fired ceramic material having the above-mentioned composition at 800 to 1000 ° C. It is possible to manufacture a high-quality low-temperature fired ceramic substrate having both a high Qf value that can be applied to higher frequencies and higher frequencies and a substrate strength that is required to ensure reliability.

Further, in the present invention, since the low temperature fired ceramic substrate contains an appropriate amount of BaO, the Qf value of the low temperature fired ceramic substrate can be increased to 3000 GHz or more.

Furthermore, in the present invention, since the low temperature fired ceramic substrate contains appropriate amounts of ZnO and SnO ₂ , the Qf value of the low temperature fired ceramic substrate can be further increased and the firing temperature can be lowered. it can.

Further, in the present invention, since the low-temperature fired ceramic substrate having the above composition and the low-melting-point metal wiring conductor are fired at the same time, a wiring conductor having low resistance and excellent electrical characteristics is formed in the inner layer or surface layer of the substrate. It is possible to manufacture the high Qf-valued low temperature fired ceramic substrate having one firing step.

In the eighth aspect, BaO is added only to the aggregate of the low temperature fired ceramic material, and B is added to the glass powder.
Since SrO is added instead of aO, the mechanical strength of the substrate can be further improved, and the Qf value of the low temperature fired ceramic material can be increased to 3000 GHz or higher, which corresponds to the recent remarkable speeding up and high frequency. can do.

Further, according to claim 9, since appropriate amounts of ZnO and SnO ₂ are added to the glass raw material, the Qf value can be further increased and the melting point of the glass can be lowered,
The glass powder can be easily manufactured.

Further, in claim 10, the aggregate of Al ₂ O _{3 is used.}
The content is 33 with respect to the total weight of the low temperature fired ceramic material.
Since the content is ˜39.5% by weight, it is possible to secure the bending strength and sinterability that can be practically used.

According to the eleventh aspect of the present invention, the low temperature fired ceramic substrate is manufactured by firing the ceramic raw substrate formed by using the low temperature fired ceramic material having the above composition at 800 to 1000 ° C. It is possible to manufacture a high-quality low-temperature fired ceramic substrate having both a high Qf value that can be applied to higher frequencies and higher frequencies and a substrate strength that is required to ensure reliability.

According to the twelfth aspect, since the low temperature fired ceramic substrate contains an appropriate amount of BaO, the Qf value of the low temperature fired ceramic substrate can be increased to 3000 GHz or more. Moreover, since the appropriate amount of SrO is contained, the bending strength of the substrate can be increased to 200 MPa or more.

Further, according to the thirteenth aspect, since the low temperature fired ceramic substrate contains appropriate amounts of ZnO and SnO ₂ ,
The Qf value of the low temperature fired ceramic substrate can be further increased, and the firing temperature can be lowered.

Further, in claim 14, since the low temperature fired ceramic substrate having the above composition and the wiring conductor of the low melting point metal are fired at the same time, a wiring conductor having low resistance and excellent electrical characteristics is formed in the inner layer or the surface layer of the substrate. It is possible to manufacture the high Qf-valued low temperature fired ceramic substrate having one firing step.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a low temperature fired ceramic multilayer substrate showing an embodiment (1) of the present invention.

[Explanation of symbols]

11a, 11b, 11c ... Green sheets of low temperature fired ceramics, 12 ... Via holes, 13 ... Via conductors, 14 ...
Inner layer wiring conductor, 15 ... Surface layer wiring conductor.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4G030 AA08 AA09 AA10 AA32 AA35                       AA36 AA37 AA39 BA12 CA08                       GA14 GA15 GA17 GA20 GA27                 5E346 AA12 CC18 CC32 CC38 CC39                       DD02 DD34 DD45 EE24 EE27                       EE29 FF18 GG04 GG05 GG06                       GG09 HH06 HH11 HH32                 5G303 AA05 AB08 AB12 AB15 BA12                       CA03 CB01 CB02 CB03 CB06                       CB30 CB31 CB32 CB38

Claims (14)

[Claims] 1. An aggregate containing Al ₂ O ₃ as a main component: 35 to 35
And 40 _{wt%, SiO 2 -CaO-B 2} O 3 -Al 2 O
_In a low temperature fired ceramic material obtained by mixing ₃ type glass powder: 60 to 65% by weight, the aggregate is B based on the total weight of the low temperature fired ceramic material.
aO is included in an amount of 0.5 to 2.0% by weight, and the glass powder is BaO based on the total weight of the glass powder.
6.4-18% by weight of a low temperature fired ceramic material. 2. The glass powder comprises SiO ₂ : 45 to 55% by weight and CaO: 15 to 15% by weight based on the total weight of the glass powder.
21 wt%, B ₂ O _3: 6.5~7.7 wt%, Al ₂
O _3: 4.2 to 5.1 wt%, BaO: 6.4 to 18 wt%, ZnO: 1.5 to 2.5 wt%, SnO _2: 2~
The low temperature fired ceramic material according to claim 1, which contains 4% by weight and impurities: 2% by weight or less. 3. The low temperature fired ceramic material according to claim 1, wherein the aggregate contains 33 to 39.5% by weight of Al ₂ O ₃ with respect to the total weight of the low temperature fired ceramic material. . 4. A low temperature fired ceramic substrate obtained by firing a ceramic raw substrate formed by using the low temperature fired ceramic material according to claim 1 at 800 to 1000 ° C. 5. SiO ₂ : 27-35.8 wt%, Ca
O: 9 to 13.7% by weight, B ₂ O ₃ : 3.9 to 5% by weight, Al ₂ O ₃ : 36 to 42.8% by weight, BaO: 4.
A low temperature fired ceramic substrate containing 3 to 13.7% by weight. 6. ZnO: 0.9-1.6% by weight, SnO
₂ : The low-temperature-fired ceramic substrate according to claim 5, containing 1.2 to 2.6% by weight. 7. A low-melting-point metal wiring conductor co-fired with a ceramic substrate is provided.
4. A low temperature fired ceramic substrate according to any one of 1. 8. An aggregate containing Al ₂ O ₃ as a main component: 35 to 35
And 40 _{wt%, SiO 2 -CaO-B 2} O 3 -Al 2 O
_In a low temperature fired ceramic material obtained by mixing ₃ type glass powder: 60 to 65% by weight, the aggregate is B based on the total weight of the low temperature fired ceramic material.
aO is contained in an amount of 0.5 to 2.0% by weight, and the glass powder contains SrO based on the total weight of the glass powder.
11 to 18.8% by weight of a low temperature fired ceramic material. 9. The glass powder comprises SiO ₂ : 47 to 55% by weight, CaO: 10 to 10 based on the total weight of the glass powder.
14.4 wt%, SrO: 11 to 18.8 wt%, B ₂
O _3: 6.5 and 7.2 wt%, Al ₂ O _3: 4.2~
5.0 wt%, ZnO: 4.5-5.5 wt%, SnO
The low temperature fired ceramic material according to claim 8, characterized in that it contains ₂ : 2.0 to 4.3% by weight and impurities: 2% by weight or less. 10. The low temperature fired ceramic material according to claim 8, wherein the aggregate contains 33 to 39.5% by weight of Al ₂ O ₃ with respect to the total weight of the low temperature fired ceramic material. . 11. A low temperature fired ceramic substrate obtained by firing a ceramic raw substrate formed by using the low temperature fired ceramic material according to claim 8 at 800 to 1000 ° C. 12. SiO ₂ : 28.2 to 35.8 wt%, CaO: 6.0 to 9.4 wt%, BaO: 0.5 to
2.0 wt%, B ₂ O _3: 3.9~4.7 wt%, Al
₂ O ₃ : 32.5 to 42.8 wt%, SrO: 6.6 to
A low temperature fired ceramic substrate containing 12.2% by weight. 13. ZnO: 2.7 to 3.6% by weight, Sn
The low temperature fired ceramic substrate according to claim 12, wherein O ₂ is contained in an amount of 1.2 to 2.8% by weight. 14. The low temperature fired ceramic substrate according to claim 11, which has a wiring conductor of a low melting point metal which is fired at the same time as the ceramic substrate.