JPS63248199A - Multilayer interconnection circuit board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [J Already Required] Glass with a silica content of 96 to 100% by weight and a softening point of 10
Weight ratio with glass below 00℃ is 20:80~80
A multilayer wiring circuit board using, as an insulating material, a glass ceramic obtained by firing a composition containing 2 to 10 parts by weight of alumina based on 100 parts by weight of a total of 100 parts by weight.

[Industrial application field]

The present invention relates to a multilayer wiring circuit board capable of high-speed signal transmission.

[Conventional technology]

Multilayer wiring circuit boards can be used as conductive materials to reduce volume! L (It is advantageous to use copper or gold, which has a small resistivity, and as a ceramic material, it can be fired densely at a temperature lower than the melting point of these conductor materials, and has a small coefficient of thermal expansion. It is necessary that no cracks occur during the cooling process of each fired product, and it is desirable that the fired product has a low dielectric constant to enable high-speed signal transmission.

Among ceramic materials, quartz glass has a dielectric constant of (3,
8, which is the smallest, but has a softening point of 1400°C or higher,
)1,1 or cannot be fired simultaneously with gold. If you mix high silica glass with low softening point glass and fire it,
A ceramic material containing high silica glass as particles in low softening point glass can be obtained. However, low softening point glass has high l! :a is separated into a flux phase containing R201 and the like and a 5i02 phase, and the 5i02 phase undergoes a phase transition to crystallize into cristobalite, which has a large coefficient of thermal expansion. Therefore, it is necessary to prevent cristobalite phase transition.

For example, in JP-A-59-11700, the conductor material is copper or copper, the insulating material is silica, and the softening point is 1050.
Disclosed is a ceramic multilayer wiring circuit board formed of glass having a temperature of 0.degree. C. or less. The obtained ceramic material exhibits a small dielectric constant of 4.2 to 5.2. However, although it is not described in this publication, it is presumed that it has the disadvantage of being susceptible to cracking during the cooling process after firing.

[Problem that the invention seeks to solve]

An insulating material obtained by firing a glass-ceramic composition containing high silica glass and low softening point glass has a low dielectric constant, but is susceptible to cracks.

[Means for solving problems]

The above-mentioned spoon point is determined when the weight ratio of glass with a silica content of 96 to 100% by weight and glass with a softening point of 1000°C or less is 20%.
: ) (0 to 80 : 20, with respect to a total amount of 100 parts by weight, a composition containing 2 to 10 parts by weight of alumina is fired to produce a multilayer glass ceramic as an insulating material. This problem can be solved by a printed circuit board.

[For production]

The addition of alumina prevents the glass, which has a low softening point of 1000° C. or lower, from undergoing a phase transition to cririsparite, keeps the coefficient of thermal expansion small, and prevents cracks from occurring during firing and cooling. When the amount of alumina added exceeds 10 parts by weight to 100 parts by weight of high silica glass and low softening point glass, the dielectric constant of the fired product increases, and when it is less than 2E1, the softening temperature decreases. The point glass undergoes a phase transition to cristobalite, increasing its coefficient of thermal expansion, and cranking occurs during firing and cooling. Furthermore, when adding 10 parts by weight of alumina to 100 parts by weight of a combination of high silica glass and low softening point glass, if the low softening point glass is less than 20 parts by weight and the high silica glass is more than 80 parts by weight, A dense fired body cannot be obtained. In addition, the above combination
When adding 2 parts by weight of alumina to 100 parts by weight, if the low softening point glass is more than 80 parts by weight and the high silica glass is less than 20 parts by weight, the shape will change during firing.

〔Example〕

1 garden ■ Quartz glass with soil dielectric constant 3.8, and Sin□81 weight 9
A, R20i13jtj amount%, AI+0* 2% by weight,
A low softening point glass containing 204% by weight of Na and having a softening point of 820° C. was used.

The dielectric constant of this glass was 4.6. Each powder of glass, quartz glass, and alumina (average particle size is 3 μm)
m) was weighed so that the weight ratio was 30nia 0:3, polyvinyl butyral as a binder, dibutyl phthalate as a plasticizer, and methyl ethyl ketone as a solvent were added and wet mixed using a conventional method, and a thickness of 300 μm was obtained using a doctor blade method. A green sheet was formed.

After punching out a 100+n green sheet and drilling through holes, we screen printed copper conductor paste to form a wiring pattern, aligned this, stacked 10 layers, and pressed at a temperature of 130°C. After the integration, they were fired in a nitrogen stream at a temperature of about 100°C (1°C) for 4 hours to form a multilayer glass circuit board.

As a result of measurements, this substrate has a low dielectric constant of 4.2, a high density of 99%, and a thermal expansion coefficient of 2.
It was as small as Ox 10-'/°C.

Fertility J - 96% silica-containing glass with dielectric constant 3.8, and S
iO□70% by weight, Bzo*25% by weight, AI! 033
Heavy h! %, Nf1202 double star%, softening point 710℃
, except that low softening point glass with a dielectric constant of 4.1 was used.
A multilayer glass substrate was produced using the same steps as in Example 1.

The dielectric constant of this substrate was as low as 4.1, the density was as high as 99%, and the coefficient of thermal expansion was as small as 2.0 x 10-''/'C.

The quartz glass, low softening point glass, used in Example 1 as the raw material for Chishinl Kusho,
Using 31 parts of alumina and 31 parts of alumina, and varying the iut ratio of silica glass to low softening point glass, substrate samples were prepared and the density shape retention, dielectric constant, and coefficient of thermal expansion were measured. evaluated. As shown in Table 1, the results show that in the range of 20 to 80% by weight of silica glass and 80 to 20% by weight of low softening point glass, the shape can be maintained, the density is 98% or more, and the dielectric The rate is 4
．． 1 to 4.4, thermal expansion coefficient is 1.8 to 2.4 X 10
-6/"C, Table 1 The quartz glass used in Example 1 as a raw material, low softening point glass,
and alumina, the weight ratio of quartz glass to low softening point glass was fixed at 70:30, and the amount of alumina added was 2
．． It was fired in varying amounts of 0 to 10 parts by weight, and the density, shape retention, dielectric constant, and coefficient of thermal expansion of the fired body were measured.

As shown in Table 2, when the amount of alumina added is 2 to 10 parts by weight with respect to 100 parts by weight of the quartz glass and low softening point glass in the above weight ratio, firing is possible without cracking, and the dielectric The ratio was also small at 4.2 to 4.6.

Table 2

Claims (1)

[Claims] 1. The weight ratio of glass with a silica content of 96 to 100% by weight and glass with a softening point of 1000°C or less is 20:80 to 80.
:20 to 100 parts by weight of alumina
A multilayer wiring circuit board characterized in that an insulating material is a glass ceramic obtained by firing a composition containing 10 parts by weight. 2. The circuit board according to claim 1, wherein the low softening point glass is borosilicate glass.