JPS6144760A - Insulative ceramic composition - 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] [Industrial application field] The present invention relates to a ceramic composition that can be used as a material for a circuit board.

In particular, the present invention relates to a ceramic composition suitable as a material for multilayer circuit boards.

[Conventional technology]

Today's 5 circuit boards, which require miniaturization of electrical circuit devices, are
As ceramics become more and more multi-layered, smaller, and thinner, porcelain is used that has properties such as high insulation and high bending strength. In addition, in order to reduce the manufacturing cost of multilayer circuit boards, it has been necessary to lower the firing temperature and use a non-oxidizing atmosphere so that relatively inexpensive conductive materials (for example, base metals such as nickel) can be used for wiring. A firing method was tried.

Furthermore, as the substrate becomes thinner, the wiring pattern of the internal circuit becomes more visible from the outside, so from the viewpoint of maintaining security, a porcelain material with high light-shielding properties is required.

[Problem that the invention seeks to solve]

However, many of the porcelains fired in a non-oxidizing atmosphere have a characteristic of having low light shielding properties after firing. Methods of increasing light shielding include adding ceramic substrate materials such as Cub), jb203,
There is a method of adding an oxide such as V205. However, when porcelain containing these materials is fired in a non-oxidizing atmosphere, there is a drawback that the insulation resistance value of the porcelain becomes low.

The present invention was made to solve the above-mentioned problems with conventional porcelain materials, and aims to provide a porcelain composition that has high light-shielding properties and high insulation properties.

[Means to solve the problem]

The ceramic composition of the present invention contains 0.5 to 10 mol% of Li2Q.
and Ca O, S r O, B a O, Z n O
5 to 45 mol% of a component consisting of one or more of the following, 1 to 40.7 mol% of MgO, Al 203'fc 1
~40% Le% + Z r O2 1-30.3 mol% SiO2 12.8-65.6 mol% +'C
It is obtained by firing a mixture containing 0.3 to 7 mol% of r203 in a non-oxidizing atmosphere.

〔Example〕

Below, as an example of the present invention, samples were prepared from porcelain compositions with nine different contents of each component, and the test results and the like conducted on each sample will be described.

First, taking Sample 1 as an example, to explain the preparation method and conditions for the samples listed in the attached table, first, 50% SiO2 powder was
．． 3g, CaC0:+ powder 24.5g, MgO powder 3.0g, Zr O2 powder 1.7g, Al2O+ powder 5.9g, L 12CO3 powder 10.3g, Cr
Weigh 4.3 g of 203 powder. In addition, the above Ca, L
The carbonate powders used in i were all stable in the air.

The weighed powders were placed in a ball mill and wet mixed by ball milling for about 15 hours.

Next, to the same material, 12% by weight of acrylic resin, 0.5% by weight of allylsulfonic acid, and 30% by weight of water were added and stirred to prepare a slurry. Next, a long unsintered porcelain sheet was made from this slurry by a doctor blade method, and this was cut into 10 ω square pieces.

Three types of samples were prepared from the cut unsintered porcelain sheets according to the purpose of the test.

That is, stacking 6 of the above sheets, 200 kg/c
From a 0.1 cm thick plate laminated under a pressure of nl.

A disk-shaped sample punched out with a diameter of 1.6 cm and a 0.2 ann thick sample made by stacking 12 of the above sheets and laminating them in the same way.
The length of the board is 3.6CI1. A prismatic sample cut to a width of 0.4 CI11 and the above sheet 5 mm in length.

Cut it to 3cm wide and use Ni paste to draw a straight line 3ca long and 0.03cm wide in the center of one side of it to O,'05cm.
A plurality of rectangular plate-shaped samples were each produced by screen printing five lines in parallel at intervals.

These samples were then heated at 1 hour per hour to 600°C in air.
The temperature was raised at a rate of 0.000C to burn off binder components such as acrylic resin. After that, the inside of the furnace was changed to a reducing atmosphere of 97.0% by volume of N2 + 3.0% by volume of H2.
Sample 1 was obtained by firing while maintaining the temperature at 00°C for 3 hours.

The above firing temperature FT at this time is shown in the separate table.

This sample was tested using the following method. First, let's talk about the electrical characteristics.

Using the disk-shaped sample described above, indium-gallium alloy was coated on both sides, electrodes with a diameter of 1.4 cm were provided, and the relative dielectric constant ε, quality factor Q, and resistivity ρ (
ΩcIn) was measured. The relative dielectric constant ε is calculated from the capacitance measured at a frequency of IMHz at a temperature of 25 ° C.
Q was measured under the same conditions as the capacitance above. In addition, the resistivity ρ is determined by applying a DC voltage of 500μ and 6
Calculated from the insulation resistance value after 0 seconds.

Physical 9 For mechanical properties, the thermal expansion coefficient and bending strength τ were measured using a prismatic sample with a thickness of 0.2 cm.
This is shown in the attached table. The thermal expansion coefficient was determined by measuring the linear expansion coefficient α (/'C) between 20 and 500°C, and the bending strength τ was determined according to the three-point bending strength of JIS-R1601.

Furthermore, regarding the light-shielding property, we used a rectangular plate-shaped sample with five lines drawn on one side with Ni in advance.If these lines cannot be seen through to the naked eye from the back side, the light-shielding property is good; It was determined that the light shielding property was poor.

Hereinafter, for Samples 2 to 78, each porcelain material powder was prepared so that the composition of the porcelain had a content ratio as shown in each column of the attached table, and was produced from this powder in the same manner and under the same conditions as Sample 1 above. However, the firing temperature FT was different and was carried out at the temperatures shown in each column of the attached table. In addition, for each sample made in this way, the above-mentioned properties were measured using the same method and conditions as Sample 1, and the linear expansion coefficient α, bending strength τ, resistivity ρ, and light shielding properties of each sample were shown in the attached table. shown in each column. In addition, all the numerical values showed the average value of the measured value obtained about several samples.

As is clear from the same table, these samples 1 to 78 are
In both cases, the firing temperature FT is 1250°C or less, the linear expansion coefficient α is 6.5X10'/°C or less, and the bending strength τ is 1500 kg.
/ cd or more, the resistivity ρ was 1×10 13 Ωcm or more, and the light shielding properties were all good. Note that these samples all have a dielectric constant ε of 9 or less and a Q of 500 to 2.
000, which is a practical value for 9 circuit board materials. Please note that these specific figures have been omitted from being listed in the attached table.

[Comparative example]

On the other hand, using a porcelain material that does not meet the requirements for the content ratio above, and using the same method and conditions as the above sample, 79 to 91
Thirteen samples were prepared up to the number. However, the firing temperature FT is
Each test was conducted at a different temperature as shown in each column of the attached table. Note that there are some products that cannot be sintered in a general industrial kiln because the temperature range for sintering is narrow, and these are shown in the attached table.

In addition, each sample made in this way was tested under the same method and two conditions as above, and the linear expansion coefficient α, bending strength τ, resistivity ρ, and light shielding properties are shown in the attached table.

[For production]

The reason why the components of the porcelain composition according to the present invention are limited as described above is as follows.

(If the content of 11Si02 is too low, the firing temperature FT will be high; if it is too high, the firing temperature FT will be high.

For example, among samples 1 to 78, the SiO2 content is 12.
Sample 70 has the lowest amount of 8 mol%, but while this could be sintered at 1250°C,
．． In sample 79 with a content of 0 mol%.

Sintering required a temperature of 1300°C. On the other hand, samples 1 to 78
Among them, sample 1 has a relatively high SiO2 content of 60.0 to 65.6 mol%; 10
Sample 80 containing 68.0 mol% of 3i02 was able to be sintered at a temperature of 00 to 1200°C.
In this case, a temperature of 1300°C was required for sintering.

(21If the content of components consisting of one or more of CaO, SrO, BaO, and ZnO is too small, the sintering temperature will be too high.
On the other hand, if the amount is too high, the range of temperatures that can be sintered will be narrowed.

For example, among samples 1 to 78, the total amount of these oxides is 5.
Sample 12.14゜16~2 has the smallest amount of 0 mol%.
0.22.44 and 48, but both of these are 11
Whereas it could be sintered at a temperature of 00 to 1150°C.

Sample 81, which had a low content of the above-mentioned oxides at 3.0 mol %, required a temperature of 1300° C. for sintering. on the other hand.

Samples 29, 52, 77 and 78, which had a relatively large amount of the above oxides (41.1 to 45.0 mol%) in Samples 1 to 7B+71, could all be sintered at a temperature of 950 to 1050°C, but Sample 8
When the content is even higher, such as 50.0 mol%, as in No. 2, the range of temperatures at which sintering can be performed is narrow, and sintering cannot be performed in a general industrial kiln.

+3) If the MgO content is too low, the range of temperatures that can be sintered will be narrow; if it is too high, the firing temperature FT will increase, and the insulation properties will decrease.

For example, among samples 1 to 78, the one with the lowest MgO content of 1.0 mol% is 2. 3.7-10. '13-15°19, 21.26.28.30. -32.34~36.
Samples such as 4F 50.55゜57, 59.73.77, 78, etc. could all be sintered at a temperature of 950 to 1200°C, but 0.1 mol% M below this temperature
Sample 83 containing gO had a narrow range of temperatures at which it could be sintered, and could not be sintered in a general industrial kiln. On the other hand, among samples 1 to 78, samples 18゜56, 33.2 to 40.7 mol%, and
70, but while all of these could be sintered at a temperature of 1150 to 1250°C, 45.0 mol%
Sample 84 containing MgO required a temperature of 1350° C. for sintering. Moreover, in the former case, the resistivity ρ is lXl01
It was over 3Ωcm, but the latter was as low as 1×1Q11Ωcm.

(41Al'201) has excellent mechanical strength, and when the amount is large, the bending strength is high, but on the other hand, when it is too large, the firing temperature FT becomes high.

For example, in samples 1 to 78, this content is 31.6 to 4
Sample 19.23.49.57.70 with a relatively large number of 0.0
In this case, a high bending strength of 2400 to 2600 kg/cj was obtained, and it was possible to sinter at a temperature of 1150 to 1250°C. However, in sample 85 containing Al2O3 higher than this at 45.0 mol%, there is no tendency for the bending strength to improve to 2500 kg/csA.

Sintering required a temperature of 1300°C.

If the content of f51 Z r O2 is small, the insulation properties will be reduced, and if it is too large, the firing temperature FT will become high.

For example, among samples 1 to 78, the one with the lowest ZrO2 content of 1.0 mol% is 1, 2, 4, 6, 7°9, 12.13
．． 16.17.21.23.27.29.31~33°36~3B, 49. '52.56.57.60.6
Samples such as L 65.70.74゜76 had a resistivity ρ of 1×1013 Ωcm or more, whereas sample 86 with a content of 0.1 mol% or less had a resistivity ρ of was lXl0IIΩcIll. Also,
25.0 to 30.3 mol% and ZrO in samples 1 to 78
Samples 20 and 58, which have a relatively high content of 2, are 115
While it was possible to sinter at a temperature of 0 to 1200°C (7), sample 87 with a higher content of 33.0 mol % required a temperature of 1300'c for sintering.

(If the amount of 61Li20 is too small, the thermal expansion coefficient will increase, and if it is too large, the insulation properties will decrease.

゛For example, among samples 1 to 78, the one with a relatively low Li2O content of 0.5 to 0.9 mol% is 53゜58,6
4.67 and 77, both of which have linear expansion coefficients α of 5.8 to 6.5 x 10-6/”c
On the other hand, in sample 88 with a lower content of 0.2 mol%, the linear expansion coefficient α is 7.2X10-
On the other hand, among samples 1 to 87, samples such as 1゜9 and 22.24, which have a relatively high Li2O content, have resistivity ρ of 1×1Q13ΩcII+ or more. In contrast, sample 8 with the same content of 12.0 mol%
9, the resistivity ρ was as low as 1X10IIΩcm.

If the content of +71Cr203 is too small, good light-shielding properties cannot be obtained, and on the other hand, if it is too large, the resistivity and bending strength will decrease.

For example, samples 1 to 1 with a Cr2O3 content of 0.3 mol%
In the sample such as 14.15.44: 56, which is the smallest among 78, the sintering temperature was 1150 to 1250 °C, the bending strength was 1700 to 1900 kg/cJ, and the light shielding property was also good. Sample 90 with a small amount of 0.1 mol%
In this case, the light shielding property was poor. Furthermore, among samples 1 to 78, sample 25.55.57.62.67, which has a relatively large Cr2O3 content of 5 to 7 mol%, has a resistivity ρ of lX1013Ω! Above, bending strength: <2300~260
0 kg/C-, but in sample 91 with 12 mol%, the resistivity ρ was as low as 1X10''Ωcm, and the bending strength was also as low as 1500 kg/ctl.

〔Effect of the invention〕

As explained above, the porcelain composition according to the present invention can be sintered at a relatively low temperature of 1250° C. or lower in a non-oxidizing atmosphere.

High light-shielding properties and practically sufficient insulation resistance can be obtained. Therefore, it is possible to manufacture the substrate at low cost, and it is also possible to reduce the thickness of the substrate.

Moreover, the confidentiality of the wiring pattern can be maintained even on a thinned board.

Claims (1)

[Claims] 0.5 to 10 mol% of Li_2O, CaO, SrO,
5 to 45 mol% of components consisting of one or more of BaO and ZnO, 1 to 40.7 mol% of MgO, and Al_2O_3
1 to 40 mol% and 1 to 30.3 mol% of ZrO_2
, 12.8 to 65.6 mol% of SiO_2, and Cr_
An insulating ceramic composition characterized in that it is made by firing a mixture containing 0.3 to 7 mol% of 2O_3 in a non-oxidizing atmosphere.