CN104036876B - A kind of preparation method of high temperature copper electric slurry - Google Patents

Abstract

A preparation method of high-temperature copper electronic paste, respectively preparing 1 μm or 15 μm copper powder mixed solvent; removing excess H ⁺ in the 1 μm or 15 μm copper powder mixed solvent to obtain pre-coated 1 μm or 15 μm copper powder; terpineol, Ethyl cellulose, ethyl acetate, polyether defoamer, aminopropyltriethoxysilane are mixed, heated in a water bath until completely dissolved to obtain an organic vehicle; pre-coated 1 μm copper powder, pre-coated 15 μm copper powder, Mix the glass powder and the organic carrier evenly. The preparation method of the high-temperature copper electronic paste of the present invention has a simple preparation process, can be produced without special equipment, and effectively reduces production costs; the prepared copper electronic paste not only has excellent electrical conductivity, but also can be stored for a long time.

Description

A kind of preparation method of high temperature copper electronic paste

technical field

The invention belongs to the technical field of preparation of electronic packaging materials, and in particular relates to a preparation method of high-temperature copper electronic paste.

Background technique

As a new type of material, electronic paste is far superior to traditional circuit equipment (such as resistance wire, electric heating tube, etc.), and has the characteristics of environmental protection, high efficiency and energy saving, and its cost is also close to that of traditional materials. App direction.

At present, many types of Au, Ag and complex doped noble metal conductive pastes have been developed. Although they have excellent conductive properties, they are expensive and have low adhesion to the substrate. They are also used for conductive strips of thick film circuits and electrode terminal materials of capacitors. The phenomenon of electron migration occurs at the time, which reduces the conductivity of the conductive paste.

In the metal system, copper has a wide source and low cost. Cu has better high-frequency characteristics and conductivity than Au. The volume resistivity of copper (1.70×10 ^-10 Ω cm) is second only to that of silver. (1.62×10 ^-10 Ω·cm), good electrical conductivity and more importantly, no defects of Ag ⁺ migration. Metal copper belongs to the transition group metal, its chemical properties are very active, it is easy to oxidize when in contact with air at normal temperature, and there are problems such as easy agglomeration and low bonding strength with the matrix. Therefore, it is necessary to find a copper powder surface modification process that can improve the oxidation resistance of the ultrafine copper powder surface, and to prepare an environmentally friendly high-temperature copper electronic paste that can be industrially applied, has excellent electrical conductivity, and can be stored for a long time, thereby improving electronic performance. The conductivity and high-frequency characteristics of components reduce the production cost of manufacturers and improve their competitiveness.

Contents of the invention

The purpose of the present invention is to provide a method for preparing high-temperature copper electronic paste, which solves the problems of easy oxidation and agglomeration of copper electronic paste.

The technical solution adopted in the present invention is a method for preparing high-temperature copper electronic paste, the specific steps are:

Step 1, preparing 1 μm copper powder mixed solvent and 15 μm copper powder mixed solvent respectively;

Step 2, removing excess H ⁺ in the 1 μm copper powder mixed solvent and 15 μm copper powder mixed solvent obtained in step 1 to obtain pre-coated 1 μm copper powder and pre-coated 15 μm copper powder;

Step 3, mixing terpineol, ethyl cellulose, ethyl acetate, polyether defoamer, and aminopropyltriethoxysilane, heating in a water bath at 60-90°C until completely dissolved, to obtain an organic carrier;

Step 4, uniformly mix the coated 1 μm copper powder obtained in step 2, pre-coated 15 μm copper powder, glass powder and the organic vehicle obtained in step 3 to obtain a high-temperature copper electronic paste.

The present invention is also characterized in that,

The preparation method of 1 μm copper powder mixed solvent and 15 μm copper powder mixed solvent in step 1 is as follows: polyethylene glycol and 1 μm copper powder or 15 μm copper powder are mixed according to the mass ratio of 1-3:1-4, and the speed is 5000 rpm Centrifuge in a centrifuge at ~10000rpm for 10-30min and then stand still for 1-3h to obtain a mixed solvent of 1 μm copper powder or a mixed solvent of 15 μm copper powder.

The specific implementation method of step 2 is: add absolute ethanol to the 1 μ m copper powder mixed solvent or 15 μ m copper powder mixed solvent obtained in step 1, and then adopt a speed of 5000 ~ 10000 rpm to magnetically stir for 10 ~ 30 minutes and then let it stand for 20 ~ 50 minutes. Remove the supernatant liquid, repeat 2 to 3 times, and then perform drying treatment under a nitrogen-protected atmosphere to obtain pre-coated 1 μm copper powder and pre-coated 15 μm copper powder.

The drying temperature is 100°C-150°C, and the drying time is 2-4 hours.

In step 3, the volume ratio of terpineol, ethyl cellulose, ethyl acetate, polyether defoamer, and aminopropyltriethoxysilane is 60-80:6-10:6-15:2-5:2 ~5.

In step 4, the mass ratio of pre-coated 1 μm copper powder, pre-coated 15 μm copper powder, glass powder and organic vehicle is 13-16:54-60:5-12:5-25.

The beneficial effect of the present invention is,

1. The preparation method of the high-temperature copper electronic paste of the present invention uses polyethylene glycol as a reducing agent, a dispersant and a stabilizer to pre-coat copper powder in an aqueous solution, remove the oxide layer on the surface, and obtain through magnetic stirring and standing Copper powder pre-coated body, and then dried to obtain coated copper powder; then use terpineol, ethyl cellulose, ethyl acetate, polyether defoamer, aminopropyltriethoxysilane, glass powder to prepare high temperature Copper electronic paste, the prepared copper paste is screen-printed on an alumina ceramic substrate, and the copper paste is dried and sintered at an appropriate temperature and time to obtain a conductive copper film that can be used for electronic packaging coatings.

2. The preparation method of the high-temperature copper electronic paste of the present invention has a simple preparation process and can be produced without special equipment, which effectively reduces the production cost; the prepared copper electronic paste not only has excellent electrical conductivity, but also can be used for a long time deposit.

3. The preparation method of the high-temperature copper electronic paste of the present invention, the prepared copper electronic paste can be sintered at high temperature, does not contain lead and cadmium components, has no pollution, and can be used for ceramic electronic components and glass electronic components and thick-film conductive tapes, etc. High temperature copper electronic paste.

detailed description

The present invention will be described in detail below in combination with specific embodiments.

The preparation method of the high-temperature copper electronic paste of the present invention is specifically implemented according to the following steps:

Step 1, preparing 1 μm copper powder mixed solvent and 15 μm copper powder mixed solvent respectively;

Mix polyethylene glycol with 1μm copper powder or 15μm copper powder according to the mass ratio of 1-3:1-4, centrifuge for 10-30min in a centrifuge with a rotating speed of 5000rpm-10000rpm, and then let it stand for 1-3h to obtain 1μm copper powder Powder mixed solvent or 15μm copper powder mixed solvent;

Step 2, removing excess H ⁺ in the 1 μm copper powder mixed solvent and 15 μm copper powder mixed solvent obtained in step 1 to obtain pre-coated 1 μm copper powder and pre-coated 15 μm copper powder;

Add absolute ethanol to the 1 μm copper powder mixed solvent or 15 μm copper powder mixed solvent obtained in step 1, then magnetically stir at a speed of 5000 to 10000 rpm for 10 to 30 minutes, then let stand for 20 to 50 minutes, pour off the clear liquid, repeat 2 to After 3 times, carry out drying treatment under the atmosphere of nitrogen protection, the drying temperature is 100 ℃ ~ 150 ℃, and the time is 2 ~ 4 hours, that is, pre-coated 1 μm copper powder and pre-coated 15 μm copper powder are obtained;

Step 3, mix terpineol, ethyl cellulose, ethyl acetate, polyether defoamer, and aminopropyltriethoxysilane in a volume ratio of 60-80:6-10:6-15:2-5 : 2 to 5 mixtures, heated in a water bath at 60 to 90°C until completely dissolved to obtain an organic carrier;

Step 4, mix the coated 1 μm copper powder obtained in step 2, the pre-coated 15 μm copper powder, glass powder and the organic vehicle obtained in step 3 in a mass ratio of 13-16:54-60:5-12:5-25 Uniform, that is, high-temperature copper electronic paste can be obtained.

The preparation method of the high-temperature copper electronic paste of the present invention uses polyethylene glycol as a reducing agent, a dispersant and a stabilizer to pre-coat copper powder in an aqueous solution, removes the oxide layer on the surface, and obtains copper powder through magnetic stirring and standing still Pre-coated body, and then dried to obtain coated copper powder; then use terpineol, ethyl cellulose, ethyl acetate, polyether defoamer, aminopropyltriethoxysilane, glass powder to prepare high-temperature copper electronics Slurry, the prepared copper slurry is screen-printed on the alumina ceramic substrate, and the sintered copper slurry is dried and sintered at an appropriate temperature and time to obtain a conductive copper film that can be used for electronic packaging coatings.

The preparation method of the high-temperature copper electronic paste of the present invention has a simple preparation process, can be produced without special equipment, and effectively reduces production costs; the prepared copper electronic paste not only has excellent electrical conductivity, but also can be stored for a long time.

The preparation method of the high-temperature copper electronic paste of the present invention, the prepared copper electronic paste can be sintered at high temperature, does not contain lead and cadmium components, has no pollution, and can be used for high-temperature requirements such as ceramic electronic components, glass electronic components, and thick-film conductive strips. Copper electronics paste.

Example 1

Step 1, mix polyethylene glycol and 1 μm copper powder according to the mass ratio of 1:1, centrifuge with a centrifuge at a speed of 5000 rpm for 30 minutes, and then let it stand for 1 hour to obtain a mixed solvent of 1 μm copper powder;

Step 2, mix polyethylene glycol and 15 μm copper powder according to the mass ratio of 1:1, centrifuge with a centrifuge at a speed of 5000 rpm for 30 minutes, and then let it stand for 1 hour to obtain a 15 μm copper powder mixed solvent;

Step 3, add absolute ethanol to the 1 μm copper powder mixed solvent obtained in step 1 or the 5 μm copper powder mixed solvent obtained in step 2, then magnetically stir at a speed of 8000 rpm for 10 minutes, then let stand for 30 minutes, pour off the supernatant, repeat 3 First, remove excess H ⁺ to prevent the copper powder from being oxidized again, and then dry it in a nitrogen-protected atmosphere at a drying temperature of 100°C for 120 minutes to obtain pre-coated 1μm or pre-coated 15μm copper powder;

Step 4, mix terpineol, ethyl cellulose, ethyl acetate, polyether defoamer, and aminopropyltriethoxysilane in a volume ratio of 80:6:8:3:3, and heat in a water bath at 80°C Until the dissolution is complete, an organic carrier is obtained;

Step 5, mix the pre-coated 1 μm copper powder, pre-coated 15 μm copper powder, glass powder and the organic carrier obtained in step 4 at a mass ratio of 15.8:59.2:5:20 to obtain high-temperature copper electronics slurry.

Example 2

Step 1, mix polyethylene glycol and 1 μm copper powder according to the mass ratio of 3:2, centrifuge with a centrifuge at a speed of 8000 rpm for 10 minutes, and then let it stand for 2 hours to obtain a mixed solvent of 1 μm copper powder;

Step 2, mix polyethylene glycol and 15 μm copper powder according to the mass ratio of 3:2, centrifuge at 8000 rpm for 10 minutes and let stand for 2 hours to obtain a 15 μm copper powder mixed solvent;

Step 3, add absolute ethanol to the 1 μm copper powder mixed solvent obtained in step 1 or the 15 μm copper powder mixed solvent obtained in step 2, then magnetically stir at a speed of 5000 rpm for 30 minutes, then let stand for 20 minutes, pour off the supernatant, repeat 3 First, remove excess H ⁺ to prevent the copper powder from being oxidized again, and then dry it in a nitrogen-protected atmosphere at a drying temperature of 120°C for 3 hours to obtain pre-coated 1μm or pre-coated 15μm copper powder;

Step 4, mix terpineol, ethyl cellulose, ethyl acetate, polyether defoamer, and aminopropyltriethoxysilane in a volume ratio of 76:8:11:2:3, and heat in a water bath at 60°C Until the dissolution is complete, an organic carrier is obtained;

Step 5, mix the pre-coated 1 μm copper powder, pre-coated 15 μm copper powder, glass powder and the organic carrier obtained in step 4 at a mass ratio of 13:54:7:5 to obtain high-temperature copper electrons slurry.

Example 3

Step 1, mix polyethylene glycol and 1 μm copper powder according to the mass ratio of 1:4, centrifuge with a centrifuge at a speed of 6000 rpm for 20 minutes, and then let it stand for 3 hours to obtain a mixed solvent of 1 μm copper powder;

Step 2, mix polyethylene glycol and 15 μm copper powder according to the mass ratio of 1:4, use a centrifuge with a rotation speed of 6000 rpm for 20 minutes and then let it stand for 3 hours to obtain a 15 μm copper powder mixed solvent;

Step 3, add absolute ethanol to the 1 μm copper powder mixed solvent obtained in step 1 or the 15 μm copper powder mixed solvent obtained in step 2, then magnetically stir at a speed of 10000 rpm for 20 minutes and then let stand for 40 minutes, pour off the layer clear liquid, repeat 2 First, remove the excess H ⁺ to prevent the copper powder from being oxidized again, and then dry it under the atmosphere of nitrogen protection, the drying temperature is 130°C, and the time is 4h, that is, the pre-coated 1μm copper powder or the pre-coated 15μm copper powder are obtained. pink;

Step 4, mix terpineol, ethyl cellulose, ethyl acetate, polyether defoamer, and aminopropyltriethoxysilane in a volume ratio of 60:7:6:2:2, and heat in a water bath at 90°C Until the dissolution is complete, an organic carrier is obtained;

Step 5, mix the pre-coated 1 μm copper powder, pre-coated 15 μm copper powder, glass powder and the organic vehicle obtained in step 4 at a mass ratio of 14:56:12:18 to obtain high-temperature copper electrons slurry.

Example 4

Step 1: Mix polyethylene glycol and 1 μm copper powder in a mass ratio of 2:3, centrifuge with a centrifuge at a speed of 10,000 rpm for 25 minutes, and then let stand for 2.5 hours to obtain a mixed solvent of 1 μm copper powder;

Step 2, mix polyethylene glycol and 15 μm copper powder according to the mass ratio of 2:3, centrifuge with a centrifuge at a speed of 10,000 rpm for 25 minutes, and then let stand for 2.5 hours to obtain a 15 μm copper powder mixed solvent;

Step 3, add absolute ethanol to the 1 μm copper powder mixed solvent obtained in step 1 or the 15 μm copper powder mixed solvent obtained in step 2, then magnetically stir at a speed of 6000 rpm for 25 minutes, then let stand for 50 minutes, pour off the layer clear liquid, repeat 2 First, remove the excess H ⁺ to prevent the copper powder from being oxidized again, and then dry it under the atmosphere of nitrogen protection. The drying temperature is 150°C and the time is 2.5h, that is, the pre-coated 1μm copper powder or the pre-coated 15μm copper powder are obtained. copper powder;

Step 4, mix terpineol, ethyl cellulose, ethyl acetate, polyether defoamer, and aminopropyltriethoxysilane in a volume ratio of 70:10:15:5:5, and heat in a water bath at 70°C Until the dissolution is complete, an organic carrier is obtained;

Step 5, mix the pre-coated 1 μm copper powder, pre-coated 15 μm copper powder, glass powder and the organic vehicle obtained in step 4 at a mass ratio of 16:60:10:25 to obtain high-temperature copper electrons slurry.

After printing the high-temperature copper electronic paste prepared in Examples 1 to 4 on the alumina ceramic substrate by screen printing technology, it was placed in a muffle furnace at 300°C and sintered in air, and the obtained samples were tested by a four-probe tester. Tested, the resulting resistance is shown in Table 1.

Table 1 Resistance of high-temperature copper electronic paste prepared in Examples 1-4

instance number Square resistance (mΩ/□) 1 36.03 2 36.29 3 18.23 4 22.39

Claims (4)

1. the preparation method of a high temperature copper electric slurry, it is characterised in that concretely comprise the following steps:

Step 1, prepares 1 μm copper powder mixed solvent and 15 μm copper powder mixed solvents respectively；

Step 2, divides in the 1 μm copper powder mixed solvent obtained to step 1 and 15 μm copper powder mixed solvents Do not add dehydrated alcohol, after then using the speed magnetic agitation 10～30min of 5000～10000rpm Stand 20～50min, outwell a layer clear liquid, do under the atmosphere of nitrogen protection after repeating 2～3 times Dry process, baking temperature is 100 DEG C～150 DEG C, the time 2～4h, i.e. obtains pre-coated 1 μm copper powder With pre-coated 15 μm copper powder；

Step 3, by terpineol, ethyl cellulose, ethyl acetate, polyether antifoam agent, aminopropyl three second TMOS mixes, and at 60～90 DEG C of heating in water bath until dissolving completely, obtains organic carrier；

Step 4, the pre-coated 1 μm copper powder that glass dust, step 2 are obtained, pre-coated 15 μm copper powder The organic carrier mix homogeneously obtained with step 3, i.e. obtains high temperature copper electric slurry.

The preparation method of high temperature copper electric slurry the most according to claim 1, it is characterised in that step In rapid 1, the compound method of 1 μm copper powder mixed solvent is: by Polyethylene Glycol and 1 μm copper powder according to quality Than be 1～3:1～4 mixing, use rotating speed be 5000rpm～10000rpm centrifuge 10～ Stand 1～3h after 30min, obtain 1 μm copper powder mixed solvent；

In step 1, the compound method of 15 μm copper powder mixed solvents is: by Polyethylene Glycol and the copper of 15 μm Powder is 1～3:1～4 mixing according to mass ratio, and using rotating speed is the centrifugal of 5000rpm～10000rpm Machine stands 1～3h after being centrifuged 10～30min, obtains 15 μm copper powder mixed solvents.

The preparation method of high temperature copper electric slurry the most according to claim 1, it is characterised in that step Terpineol, ethyl cellulose, ethyl acetate, polyether antifoam agent, aminopropyl triethoxysilane in rapid 3 Volume ratio be 60～80:6～10:6～15:2～5:2～5.

The preparation method of high temperature copper electric slurry the most according to claim 1, it is characterised in that step In rapid 4, the mass ratio of pre-coated 1 μm copper powder, pre-coated 15 μm copper powder, glass dust and organic carrier is 13～16:54～60:5～12:5～25.