JPH0489329A - Whisker compounded glass composition - Google Patents

Abstract

PURPOSE:To obtain a glass compsn. which can realize such a sintered body having low relative dielectric constant and coefft. of thermal expansion and high strength by compounding a specified amt. of whisker into a glass compsn. powder which forms a specified crystalline structure after sintering. CONSTITUTION:The whisker-compounded glass compsn. powder consists of a whisker and a glass compsn. powder which has alpha-cordierite as the main crystalline structure after sintering. The compounding ratio of the whisker is preferably <=50vol.% calculated as the density to the whole whisker- compounded glass compsn. As for the whisker, whiskers of silicon nitride, aluminum boride, and silicon carbide are preferable. The glass compsn. powder contains 48-63wt.% SiO2, 10-25wt.% Al2O3, 10-25wt.% MgO, 4-10wt.% B2O3 with one or more components selected from CaO, BaO, and SrO substituted for 0-20wt.% of the whole MgO component.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a glass composition used, for example, in the manufacture of multilayer wiring boards on which various semiconductor components are mounted and input/output terminals for electrical signals are attached.

[Conventional technology] In order to meet the demands for miniaturization and high reliability in multilayer wiring boards that are equipped with a large number of various electronic components such as LSIs,
The use of ceramics as substrate materials is becoming widespread. As a ceramic material, alumina, which has relatively high strength and is difficult to crack or chip, is often used as a preferable material. In devices that require high speeds, a substrate with a lower dielectric constant than an alumina substrate is required.Also, the coefficient of thermal expansion of alumina is about 2 that of silicon, which is the material for the LSIs etc. on which it is mounted. Since this is twice as high, there is a problem that failures may occur due to the difference in thermal expansion coefficients.

In order to solve these problems, the inventors developed a glass composition whose crystal structure after sintering is mainly α-cordierite as a substrate material with a low dielectric constant and a low coefficient of thermal expansion. The performance of the substrate obtained using this glass composition is low in terms of dielectric constant and coefficient of thermal expansion;
Although excellent, the bending strength is low at 120 to 170 MPa.
When using a wiring board for this purpose, when attaching electrical signal input/output pins to the wiring board by brazing, etc., there are problems such as cracking due to thermal stress caused by the difference in thermal expansion between the brazing material and the board, and problems with brazing. However, when load stress is applied later on, the board may peel off at the brazed area, resulting in failures such as poor continuity.

[Problems to be Solved by the Invention] An object of the present invention is to provide a glass composition that has a low dielectric constant and a low coefficient of thermal expansion, and can yield a strong sintered body.

[Means for Solving the Problems] The present invention provides that the whiskers and the crystal structure after sintering are mainly α
- consisting of a glass composition powder that becomes cordierite;
This is a whisker-containing glass composition in which the proportion of whiskers in terms of density is 50% by volume or less.

The glass composition comprising the whiskers and glass composition powder of the present invention has a significantly improved strength of a sintered body obtained by sintering, compared to a glass composition containing no whiskers. This is considered to be because the whiskers act as a dissipation source of fracture energy in the sintered body and increase the energy required for fracture, thereby improving the strength of the sintered body. In order for the whiskers to act as a dissipation source of fracture energy, it is desirable that the whiskers be dispersed as whiskers in the sintered body after sintering. Acid aluminum and silicon carbide whiskers are preferred.

A feature of the present invention is that the blending ratio of whiskers is 50% by volume or less of the entire glass composition containing whiskers in terms of density. (The following volume percentages are values calculated by density conversion) In other words, the blending ratio of whiskers is 5.
This is because if the content exceeds 0% by volume, sinterability is inhibited, a dense sintered body cannot be obtained, and the strength of the sintered body becomes low.

However, when the whisker is silicon carbide, the dielectric constant of silicon carbide is relatively large, so it is difficult to keep the proportion of the whisker-containing glass composition to less than 10% by volume to obtain a sintered body with a low dielectric constant. desirable for this purpose.

Furthermore, if the blending ratio of whiskers is too small, the effect of improving the strength of the sintered body will be poor, so it is desirable that the whiskers be blended in an amount of 2% or more by volume of the entire whisker-blended glass composition.

In the present invention, whiskers other than the above-mentioned whiskers can be used as long as they have properties similar to those of the above-mentioned whiskers.

The glass composition powder of the present invention whose crystal structure after sintering is mainly α-cordierite is S t O.

AlgOs A glass composition powder containing MgO as a main component, preferably a glass composition powder containing the following components as main components.

SiO□: 40-63% by weight A 1m Os: 10-25% by weight MgO: 10
~25% by weight The sintered body obtained using such a glass composition powder has a low dielectric constant and a coefficient of thermal expansion close to that of silicon, but depending on the blending ratio of the components, it may be difficult to sinter at temperatures above 1000°C. Unless sintered at a high temperature, a dense sintered body may not be obtained.

A multilayer wiring board manufactured using the glass composition of the present invention is usually manufactured by forming a conductor on a green sheet made of a glass composition, an organic binder, etc. and then sintering it. The conductor to be formed on this green sheet is preferably a low-resistance metal such as Au, Ag, Ag-Pd, or Cu.The melting point of these metals is around 1000°C, so multilayers can be formed without melting the conductor. In order to obtain a wiring board, the sintering temperature of the green sheet is preferably 1000°C or less. However, if the conductor is not formed on the green sheet or if a metal with a higher melting point than the metals listed above is used for the conductor, No problem occurs even if the sintering temperature of the green sheet is increased to 1000℃ or higher.
If it is desirable to carry out the temperature below ℃, use sio□-A
The glass composition powder containing I*05-MgO as a main component has the following composition: sto: 48-63% by weight A1.03: 10-25% by weight MgO: 10-25% by weight Btus: 4-10% by weight and has a composition in which 0 to 20% by weight of MgO based on the entire MgO component is replaced with at least one kind of alkaline earth metal oxide selected from CaO1BaO1SrO. is suitable.

In other words, when the composition ratio of Sing exceeds 63% by weight, the glass melting temperature increases, and the surface of the glass particles rapidly crystallizes during sintering, resulting in a lack of glass phase that helps sintering, resulting in a dense sintered body. It becomes difficult to obtain. If it is less than 48% by weight, the crystallization temperature of the glass powder increases, and the sintering temperature at which a dense sintered body is obtained becomes high, and therefore
If sintering is performed below, a problem arises in that only a sintered body in an unsintered state is obtained.

A1. Regarding the composition ratio of O, if it exceeds 25% by weight, the sintering temperature at which a dense sintered body can be obtained becomes high, and therefore, if sintered at a temperature below 1000°C, only an unsintered sintered body can be obtained. Problems that cannot be solved arise. If it is less than 10% by weight, α-cordierite crystals will decrease, and S to,
- Many MgO-based crystals precipitate, resulting in a problem of high relative dielectric constant.

Regarding the composition ratio of MgO, if it exceeds 25% by weight, it is presumed that magnesium silicate will precipitate, but the deformation during sintering will become large (which will make it impractical). If it is less than 10% by weight, This causes the problem that a dense sintered body cannot be obtained.

B20. When the composition ratio exceeds 10% by weight, foaming tends to occur during sintering, the temperature range in which sintering can be performed becomes narrow, and the strength of the sintered body decreases.

If it is less than 4% by weight, crystallization of the surface layer of the glass particles will proceed rapidly, causing a problem that a dense sintered body cannot be obtained by sintering at 1000°C or lower.

Regarding alkaline earth metal oxides to replace MgO,
In order to obtain a dense sintered body, it can be used as needed, but if the alkaline earth metal oxide to be substituted is MgO,
If it exceeds % by weight, the MgO component will decrease, causing a problem that precipitation of α-cordierite crystals will deteriorate and the dielectric constant will increase.

The whisker-containing glass composition of the present invention is preferably used in the above-mentioned multilayer wiring board, but is not limited thereto, and can be used in various applications that require high strength, low dielectric constant, and low coefficient of thermal expansion. Applicable to the field.

[Function] The glass composition powder of the present invention whose crystal structure is mainly α-cordierite after sintering has the effect that the sintered body has a low dielectric constant and a low coefficient of thermal expansion, and this glass composition powder Since the whiskers combined with the sintered body are dispersed in the sintered body, they act as a dissipation source of fracture energy,
It acts to increase the energy required to destroy the sintered body.

The glass composition powder having the composition shown in claim 3 is 1000
Sintering is possible at a sintering temperature below ℃.

[Example] Regarding Examples and Comparative Examples of the present invention, the manufacturing method and the results of performance tests will be described.

The whisker-containing glass composition and the sintered body of each Example and Comparative Example were manufactured as follows.

Each compounding component (S 10x , A 1103 , Mg 0
2B80. etc.) in the proportions shown in Table 1, put each into an alumina crucible, and heat the mixture to about 1500-1550℃.
It was heated and dissolved. The resulting melt was poured into water to form a glass composition, which was then wet-pulverized or dry-pulverized in an alumina ball mill to obtain a glass composition powder with an average particle size of 2 to 4 μm.

The glass composition powders of G-1 to G-10 in Table 1 are glass composition powders having compositions within the composition range shown in claim 3 of the present invention, and the glass compositions of G-11 to G-14 are The glass composition powder is a glass composition powder having a composition outside the composition range shown in claim 3.

Various whiskers were blended with the glass composition powder thus obtained at the volume fractions (volume % relative to the entire blend) shown in Tables 2 and 3, and ethyl alcohol was added in a nylon ball mill. 24-hour mixing,
It was dried to obtain a whisker-containing glass composition. In addition, all types of whiskers are commercially available and have an average diameter of 0.5 to 1.
．． 0 μm, average length around 10 to 100 μm, and before being blended with the glass composition powder, it was irradiated with ultrasonic waves in pure water and passed through a filter with an opening diameter of 50 μm (#325 mesh). was used.

Using a graphite mold, the whisker-containing glass composition thus obtained was heated at a heating rate of 1 in an argon atmosphere.
Hot press sintering was carried out under the conditions of 0 °C/min, sintering temperature of 1000 °C, holding time of 1 hour, and press pressure of 35 MPa.
A whisker composite glass-ceramic sintered body in the shape of a disk of mm- was obtained. The relative dielectric constant at a frequency of IMHz was measured for the obtained 50 mm disk-shaped whisker composite glass ceramic sintered body. Further, test pieces with dimensions of 4 x 3 x 35 mm were prepared from this sintered body by cutting and grinding, and the thermal expansion coefficient and bending strength by three-point bending according to JISR1601 were measured. The results are shown in Table 2.
It is shown in Table 3.

Examples 1 to 11 shown in Table 2 were carried out using glass composition powders having compositions within the composition range shown in claim 3 of the present invention, and the bending strength obtained in each case was is 20
It showed a high value of 9 to 391 MPa, and the relative dielectric constant and coefficient of thermal expansion had values sufficient for practical use. These results demonstrate that the sintered body obtained from the whisker-containing glass composition of the example of the present invention has a low dielectric constant, a low coefficient of thermal expansion, and high strength.

On the other hand, in Comparative Examples 1 to 4 in Table 3, the blending ratio of whiskers is 60 to 70% by volume, which is higher than 50% by volume.
A dense sintered body cannot be obtained, and the bending strength is 47 to 118 MP.
It was a low value of a. In addition, in Comparative Examples 5 to 8 in Table 3, the blending ratio of each component of the glass composition powder is outside the composition range shown in claim 3 of the present invention, and in this case, by blending whiskers, Furthermore, the sintering properties deteriorated, and a dense sintered body could not be obtained by sintering at 1000°C even though the blending ratio of whiskers was 10% by volume.
The bending strength was a low value of 78 to 148 MPa.

[Effects of the Invention] The sintered body made of the whisker-containing glass composition of the present invention has a low dielectric constant, a low coefficient of thermal expansion, and a strong sintered body, so it is suitable for use as a multilayer wiring board. It is now possible to provide materials that

Furthermore, when the glass composition powder having the composition of claim 3 is used, it is possible to obtain a whisker composite glass-ceramic sintered body having strong strength by sintering at a temperature of 1000°C or less. It is possible to form a low-resistance metal conductor on the green sheet and sinter this green sheet to make a multilayer wiring board without melting the low-resistance metal. It has now become possible to provide materials suitable for

Claims (3)

[Claims] (1) A whisker-containing glass composition consisting of whiskers and a glass composition powder whose crystal structure after sintering is mainly α-cordierite, and in which the proportion of whiskers in terms of density is 50% by volume or less. (2) The whisker-containing glass composition according to claim 1, wherein the whisker is at least one selected from silicon nitride, aluminum borate, and silicon carbide. (3) The glass composition powder has the following components: SiO_2: 48 to 63% by weight, Al_2O_3: 10 to 25% by weight, MgO: 10 to 25% by weight, B_2O_3: 4 to 10% by weight, and 0% to the total MgO component. Claim 1, characterized in that the powder has a composition in which ~20% by weight of MgO is replaced with at least one kind of alkaline earth metal oxide selected from CaO, BaO, and SrO. The whisker-containing glass composition according to item 1 or 2.