JPS63236784A - Metallizing paste 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 [Field of Industrial Application] The present invention relates to a metallization paste composition used for printing electrodes and wiring patterns on ceramic wiring boards.

[Prior Art] If metallization base for ceramic wiring boards) If composition is composed of a metal particle component that imparts conductivity, an adhesive component to the substrate, and an organic binder component that provides physical properties as a paste. There is. Conventionally, noble metal particles such as silver, silver-palladium, gold, and platinum have been used as the metal particle component in the metallization paste to prevent oxidation during baking of the substrate. In addition, glass powder is used as the adhesive component, and a resin, a solvent, a dispersant, etc. is used as the organic binder.

The conventional metallizing paste that uses noble metal powder as the metal powder component has the advantage of being able to bake the wiring board in the atmosphere, but because it uses noble metal as the conductive material, it suffers from large price fluctuations and is expensive. there were.

Therefore, in order to solve these problems, a metallized paste using copper powder as conductive particles, a so-called copper paste, has also been proposed. Copper is cheaper than precious metals, has the second lowest electrical resistance after silver, and is less likely to undergo migration like silver, which led to the adoption of a method of firing wiring boards in a non-oxidizing atmosphere. , is used as a metallizing paste for ceramic wiring boards.

[Problems to be solved by the invention] However, such copper paste has the following two problems.

First, although the copper material itself is cheaper than precious metals, it is suitable for metallizing paste materials.
Spherical particles of m are not easily obtained and are expensive. This is because the copper powder obtained by the chemical precipitation method, which is a common method for producing spherical copper powder, is a fine powder, but the production efficiency is low.
This is because even if a lot of time and effort are spent, only a small amount of production can be obtained.

Another problem is that it is difficult to completely remove the organic binder component used in the metallizing paste in a non-oxidizing atmosphere, and it is said that it does not decompose thermodynamically, especially at temperatures below the melting point of copper.

Therefore, in the process of baking the wiring board, delicate atmosphere control is required, such as including a small amount of oxygen in the non-oxidizing atmosphere, and the baking conditions are extremely difficult.

An object of the present invention is to provide a metallizing paste composition that can solve these problems.

[Means for solving the problem] That is, the metallized base) 1M composition according to the present invention contains 100 parts by weight of cuprous oxide (Cu20) powder and 2 to 10 parts by weight of manganese compound powder in terms of manganese monoxide compound.
parts by weight, 4 to 20 parts by weight of glass powder, and an amount of organic binder suitable for making into a paste.

[Example] Next, an example of the present invention and an example of its use will be specifically described below.

(Example 1) Cuprous oxide (Cu20) powder (average particle size 2.8u,
m) 100g and -manganese oxide (MnO) powder (
4 g of glass powder (GA-12 manufactured by Nippon Electric Glass Co., Ltd., average particle size 2.ILLm)
, 200ml of ethanol, and oleic acid (dispersant)
0.5 g were weighed and mixed in a ball mill for 16 hours. Next, the mixture was dried by heating to evaporate the ethanol, and the solid content was crushed to obtain a mixed powder.

Separately, 100g of butylcarpitol acetate
Into the mixture, 12 g of ethyl cellulose was added, heated to a temperature of 70° C. while stirring to completely dissolve the ethyl cellulose, and then naturally cooled to room temperature to prepare an organic binder.

100 g of the mixed powder, 25 g of the organic binder, and 0.5 g of oleic acid were mixed in a crusher, and then kneaded in a three-roll mill to produce a metallized paste.

Next, using the paste, separate alumina substrates (vertical 5
0mm, width 120mm, thickness 0.8mm), - side 1
．． Screen print a 5mm square pattern, a square pattern with a side of 8mm, and multiple linear patterns with a width of 0.3mm and a length of 100mm, and heat them at 120°C.
It was dried for 10 minutes at a temperature of . The coating thickness of the metalized paste after drying was approximately 35 μm.

Next, the alumina substrate was heated to a maximum temperature of 680°C in the atmosphere.
The organic binder component contained in the metallizing paste was burned and scattered by passing through a mesh belt type tunnel furnace for a total time of 50 minutes. Furthermore, N2 gas 96%-H
The alumina substrate was introduced into a mesh belt type tunnel furnace maintained in a reducing atmosphere by supplying a mixed gas of 4% of 2 gases at a flow rate of 4 m3 per hour, and the alumina substrate was heated from room temperature to 95%.
The temperature was increased at a temperature gradient of 30°C/min to 0°C, followed by 950°C.
After maintaining the temperature at ℃ for 30 minutes, let it rise to room temperature for 30 minutes.
The metallization paste was fired using a temperature profile that lowered the temperature with a temperature gradient of °C/min.

Using a board on which a copper pattern has been formed according to the above procedure, the solder adhesion strength, sheet resistance, solder resistance,
Tests and measurements of solder wettability were conducted respectively.

First, regarding the adhesion strength of the solder, we used a board on which a 1.5 mm square copper pattern was formed, soldered one end of a tin-plated annealed copper wire with a diameter of 0.6 in parallel to the board surface, and soldered the annealed copper wire parallel to the board surface. This was done by fixing the other end of the wire to a bush bull gauge and pulling it in a direction perpendicular to the board surface until the soldered part broke. Then, the load at the time of breakage was read with a push-pull gauge and converted to the load per 1 mm2 of soldered area. In this way, the breaking load per unit area was measured for 50 samples, and the average value is shown in Table 1 as the adhesion strength.

To measure the sheet resistance, use a Whiston bridge to measure the electrical resistance value between both longitudinal ends of a linear pattern with a width of 0.3 mm and a length of 100 mm formed on the substrate, and calculate this as the resistance per unit area. This was done by converting it into a value. In this way, the resistance value per unit area was measured for 50 samples, and the average value is shown in Table 1 as the sheet resistance value.

For evaluation of solder resistance, the linear pattern of the board after sheet resistance measurement was immersed in a molten solder (63S n -37P b ) bath kept at 260°C ± 5°C for 10 seconds, and then taken out. Visually observing the linear pattern 1
This was carried out by repeating this cycle until a break in the pattern was observed. As a result, if the wire was broken after 1 to 3 times, it was rejected, if the wire was broken after 4 to 6 times, it was accepted, and if it was broken after 7 to 9 times, it was considered good, and if the wire was broken after 10 times or more, the wire was broken. The results are shown in Table 1. The results are shown in Table 1.

For the solder wettability evaluation test, a board on which an 8 mm square copper pattern was formed was used, and after immersing the copper pattern in 25% rosin, molten solder (
63S n -37P b ) The test was performed by immersing the sample in a tank for 5 seconds, taking it out, and checking the degree of wetting of the solder. As a result, those with solder wetted area less than 80% of the copper area are unacceptable, 80-95% is acceptable, 96-99% is acceptable, and 100% is acceptable.
This is shown in the El column of Table 1.

(Examples 2 to 5) As shown in Table 1, in Example 1, the amount of manganese monoxide in the metallized paste was changed from 4g to 2g and 6g, respectively.
, 8 g, and 10 g, and other than that, Examples 2 to 5 were carried out using the same method and conditions as in Example 1. These results are shown in columns E2 to E5 of Table 1.

(Examples 6 to 9) As shown in Table 1, in Example 1, the amount of glass powder in the metallizing paste was changed from 10 g to 4 g, 7 g,
Examples 6 to 9 were carried out using the same method and conditions as in Example 1 except that the amounts were changed to 15 g and 20 g. These results are shown in Table 1.
It is shown in columns E6-9.

(Examples 10 to 12) As shown in Table 1, in Example 1, the type of glass powder in the metallizing paste was changed to GA-12 manufactured by Nikkei Glass Co., Ltd.
From, Nikkei Glass Co., Ltd. GA-4, Ls-0500, G
Examples 10 to 12 were carried out using the same method and conditions as in Example 1 except that A-13 was used.

These results are shown in columns EIO-12 of Table 10.

(Example 13) As shown in Figure 1, in Example 1, 4 g of manganese monoxide in the metallizing paste was replaced with manganese tetroxide (M n
30 a) Example 13 using the same method and conditions as Example 1 except for changing to 4.3 g (4 g in terms of M n O)
was carried out. The results are shown in column E13 of Table 10.

(Example 14) As shown in Table 1, in Example 1, 4 g of manganese monoxide in the metallization paste was replaced with manganese trioxide (M n
203) Example 14 was carried out using the same method and conditions as in Example 1 except that 4.58 (4 g in terms of M n O) was used. The results are shown in column El4 of Table 1.

(Example 15) As shown in Table 1, in Example 1, 4 g of manganese monoxide in the metallization paste was replaced with manganese dioxide (Mn
02) Example 15 was carried out using the same method and conditions as in Example 1 except that the amount was changed to 4.9 g (4 g in terms of Mn 2 O). The results are shown in column E15 of Table 10.

(Example 16) As shown in Table 1, in Example 1, 4 g of manganese monoxide in the metallization paste was replaced with manganese carbonate (Mn C
Example 16 was carried out using the same method and conditions as in Example 1 except that 6.5 g (4 g in terms of MnO) was used. The results are shown in the E16 column of Table 1.

(Example 17) As shown in Table 1, in Example 1, 4 g of manganese monoxide (MnO) in the metallizing paste was mixed with 2 g of manganese oxide (MnO) and 2 g of manganese tetroxide (Mn30a).
．． 15g (4g in terms of total MnO), and the glass powder was changed from GA-12 manufactured by Nippon Electric Glass Co., Ltd. to No. 4101 manufactured by Nippon Enamel Glaze Co., Ltd., but otherwise carried out using the same method and conditions as in Example 1. Example 17 was carried out. The results are shown in column E17 of Table 1.

(Example 1st day) As shown in Figure 1, in Example 1, 4 g of manganese monoxide (MnO) in the metallizing paste was replaced with 2 g of -manganese oxide and 3.24 g of manganese carbonate (Mn CO3).
(4 g in terms of total MnO), and the glass powder was changed from GA-12 manufactured by Nippon Electric Glass Co., Ltd. to No. 4121 manufactured by Nippon Enamel Glaze Co., Ltd., but otherwise Example 1 was carried out using the same method and conditions. J8 was conducted. The results are shown in the column of Table 10E1B.

(Example 19) As shown in Table 1, in Example 1, 4 g of manganese monoxide (MnO) in the metallizing paste was replaced with 2.15 g of manganese tetroxide (Mn30*) and manganese trioxide (MnO).
n203) 2.22g and manganese carbonate (Mn C03)
3.24 g (6 g in terms of total MnO), and the glass powder was changed from GA-12 manufactured by Nippon Electric Glass Co., Ltd. to No. 4138 manufactured by Nippon Enamel Glaze Co., Ltd., and the rest was Example 1.
Example 19 was carried out using the same method and conditions. The results are shown in the E19 column of Table 1.

(Example 20) As shown in Table 1, in Example 1, 4 g of manganese monoxide (MnO) in the metallizing paste was replaced with 2.15 g of manganese tetroxide (Mn30a) and manganese trioxide (Me
2n3) 2.22g and manganese dioxide (Mn 02)
2.45g (total MnO equivalent: 6g), and
Example 20 was carried out using the same method and conditions as in Example 1, except that the glass powder was changed from GA-12 manufactured by Nippon Electric Glass Co., Ltd. to No. 6310 manufactured by Nippon Enamel Glaze Co., Ltd. The results are shown in Table 1.
It is shown in the E20 column.

(Comparative Examples 1 and 2) As shown in Figure 1, in Example 1, the amount of manganese monoxide in the metallization paste was changed from 4g to 1g and 12g, respectively.
Comparative Examples 1 and 2 were carried out using the same method and conditions as in Example 1, except for changing to g.

The results are shown in columns 01 and C2 of Table 1.

(Comparative Examples 3 to 4) As shown in Table 1, in Example 1, the amount of glass powder in the metallizing paste was changed from 10 g to 2 g and 25 g, respectively.
Comparative Examples 3 and 4 were carried out using the same method and conditions as in Example 1 except for the following. The results are shown in columns C3 and C4 of Table 1.

As shown in the results of Examples 1 to 20 above, the amount of manganese compounds in the metallizing paste, when converted to manganese oxide, is 2 to 2 to 100 parts by weight of cuprous oxide.
When it is in the range of 10 parts by weight, it contributes to improving the density of metallized copper and is effective in improving solder adhesion and solder resistance. Moreover, sufficiently good solder wettability can be obtained. On the other hand, if the amount of the manganese compound in the metallizing paste is less than 2 parts by weight calculated as manganese monoxide per 100 parts by weight of cuprous oxide, soldering The adhesion strength is less than I kg/mm2, and the solder resistance is also poor, which is not preferable. On the other hand, 1
If it exceeds 0 parts by weight, solder wettability deteriorates as in Comparative Example 2, which is not preferable. Therefore, in the present invention, the amount of manganese compound in the metallized paste is limited to the above range.

When the amount of glass powder in the metallizing paste is in the range of 4 to 20 parts by weight per 100 parts by weight of cuprous oxide, it is effective in improving the adhesion strength of metallized copper to solder. , sufficiently good solder wettability and sufficiently low sheet resistance can be obtained. In contrast, the amount of the glass powder in the metallized base is 100% cuprous oxide.
If the amount is less than 4 parts by weight, as shown in the results of Comparative Example 3, the adhesion strength of the metallized copper to the solder is weak and is less than I kg/mm2, which is not preferable.

On the other hand, if it exceeds 20 parts by weight, as shown in the results of Comparative Example 4, the solder wettability is poor and the sheet resistance increases rapidly, which is not preferable. Therefore, in the present invention, the amount of glass powder in the metallization paste is limited to the above range.

In the metallizing paste according to the present invention, the particles for imparting conductivity to the metallized copper are cuprous oxide powder, and by using this cuprous oxide as the conductive material, it is possible to heat the copper in the air. After completely scattering the organic binder, it is possible to perform metallization by firing in N2 gas containing H24. In this case, the amount of the reducing gas sent into the firing furnace is 173
A moderate amount is sufficient.

[Effects of the Invention] As explained above, according to the present invention, as particles for imparting conductivity to be included in the metallizing paste,
By using cuprous oxide, the unit price of the conductive material can be significantly reduced (approximately 1,710 yen or less at the current material price) compared to the case of using metallic copper powder, and the price of the metallizing paste can be reduced. I can do it. Moreover, since the organic binder can be completely dispersed by heating in the air, the removal of the organic binder and the firing process are facilitated, improving productivity and stabilizing the properties of metallized copper. Can be done.

Claims (1)

[Claims] A metallizing paste composition containing 100 parts by weight of cuprous oxide powder, 2 to 10 parts by weight of manganese compound powder in terms of manganese monoxide, 4 to 20 parts by weight of glass powder, and an amount of organic binder suitable for paste formation. thing.