CN-122028994-A - Gallium oxide-coated silver powder, method for producing same, and conductive paste

Abstract

To provide a silver powder having reduced line resistance when an electrode is formed by pasting the silver powder obtained by modifying the surface of the silver powder, and to provide a method for producing the silver powder. When metallic silver particles are precipitated from an aqueous solution containing silver ions, a gallium compound is allowed to coexist in the aqueous solution, and a reducing agent having an effect of reducing the pH of the aqueous solution by adding the reducing agent or a reducing agent having an effect of reducing the pH of the aqueous solution by an oxidation product of the reducing agent is used as the reducing agent, whereby a gallium oxide-coated silver powder having a low resistance electrode can be obtained when the precipitated silver powder is pasted and an electrode is formed.

Inventors

• KOBAYASHI Shoya

Assignees

• 同和电子科技有限公司

Dates

Publication Date

20260512

Application Date

20250219

Priority Date

20240329

Claims (6)

1. 1. And a gallium oxide-coated silver powder comprising silver particles having a gallium oxide coated surface, wherein the gallium content is 10 mass ppm to 900 mass ppm based on the mass of the gallium oxide-coated silver powder, and wherein the cumulative 50% particle diameter D 50 of the gallium oxide-coated silver powder, measured by a laser diffraction scattering particle size distribution measuring apparatus, is 0.2 [ mu ] m to 5.0 [ mu ] m.
2. 2. The gallium oxide-coated silver powder according to claim 1, wherein the gallium amount is 10 mass ppm or more and 600 mass ppm or less with respect to the mass of the gallium oxide-coated silver powder.
3. 3. A method for producing gallium oxide-coated silver powder, comprising: A step of adding ammonia to an aqueous solution containing silver ions and a gallium compound to form a silver-ammonia complex; a step of adding a pH adjuster to the aqueous solution containing the silver-ammonia complex formed in the step to adjust the pH of the aqueous solution to 10 or more, and And a step of adding a reducing agent to the aqueous solution having the pH adjusted to 10 or more, reducing silver ions to precipitate silver particles, and adding the reducing agent to thereby adjust the pH of the aqueous solution to 3.3 to 6.5 inclusive and precipitate gallium.
4. 4. The method for producing a gallium oxide-coated silver powder according to claim 3, wherein the reducing agent is an organic compound containing 1 or 2 or more of COOH groups, CHO groups and OH groups in the molecule.
5. 5. The method for producing a gallium oxide-coated silver powder according to claim 3, wherein the reducing agent is formaldehyde.
6. 6. A conductive paste using the gallium oxide-coated silver powder according to claim 1 or 2.

Description

Gallium oxide-coated silver powder, method for producing same, and conductive paste Technical Field The present invention relates to a gallium oxide-coated silver powder suitable for use in a conductive paste for forming an electrically conductive path in an electrode, a circuit, or other element of various electronic components, a method for producing the same, and a conductive paste. In the present specification, gallium oxide is a concept including gallium oxide hydrate and gallium hydroxide. Background In the formation of electrodes, circuits, and the like of electronic components, a large amount of resin-type and firing-type silver paste has been used. In recent years, for a conductive paste using silver powder, there is a demand for a high density of a conductor pattern and a thin line for reducing the wiring thickness due to miniaturization of electronic components. In order to make the wiring finer, it is necessary to reduce the line resistance of a conductive film formed using a conductive paste. For this reason, attempts have been made to modify the surface of silver powder and to improve the electrical properties of the finally obtained conductive film. For example, patent document 1 discloses a surface-modified silver powder in which at least 1 kind of oxide or composite oxide containing a metal element belonging to groups 2 to 14 of the periodic table is fixed to the surface of metallic silver particles. The surface-modified silver powder disclosed in patent document 1 aims to suppress heat shrinkage when sintering a conductive paste containing the silver powder. Prior art literature Patent literature Patent document 1 Japanese patent laid-open No. 2001-240901 Disclosure of Invention Problems to be solved by the invention The silver powder disclosed in patent document 1 has its surface modified by fixing an oxide on its surface, but the oxides used in the examples disclosed in patent document 1 are only aluminum oxide and silicon oxide, and these oxides have high volume resistivity, so that the effect of reducing the line resistance of the conductive film is small. The technical problem to be solved by the present invention is to provide a silver powder having reduced line resistance when the obtained silver powder is pasted to form an electrode having a small line width by modifying the surface of the silver powder, and a method for producing the same. Means for solving the problems The present inventors have made intensive studies to achieve the above-mentioned problems, and as a result, have found that the line resistance of an electrode film having a thin line width, which is finally formed, can be reduced by coating a small amount of gallium oxide on the surface of silver powder. Based on the above knowledge, the present inventors have completed the present invention described below. That is, in order to achieve the above-described object, the present invention provides: (1) And a gallium oxide-coated silver powder comprising silver particles having a gallium oxide coated surface, wherein the gallium content is 10 mass ppm to 900 mass ppm based on the mass of the gallium oxide-coated silver powder, and wherein the cumulative 50% particle diameter D 50 of the gallium oxide-coated silver powder, measured by a laser diffraction scattering particle size distribution measuring apparatus, is 0.2 [ mu ] m to 5.0 [ mu ] m. (2) The gallium oxide-coated silver powder according to the item (1), preferably, the amount of gallium is 10 mass ppm or more and 600 mass ppm or less relative to the mass of the gallium oxide-coated silver powder. In the present invention, there is also provided: (3) A method for producing gallium oxide-coated silver powder, comprising: A step of adding ammonia to an aqueous solution containing silver ions and a gallium compound to form a silver-ammonia complex; A step of adding a pH adjustor to the aqueous solution containing the silver-ammonia complex formed in the step to adjust the pH of the aqueous solution to 10 or more; And And a step of adding a reducing agent to the aqueous solution having the pH adjusted to 10 or more, reducing silver ions to precipitate silver particles, and adding the reducing agent to thereby adjust the pH of the aqueous solution to 3.3 to 6.5 inclusive and precipitate gallium. (4) In the method for producing a gallium oxide-coated silver powder according to item (3), it is preferable that the reducing agent is an organic compound containing 1 or 2 or more of COOH groups, CHO groups and OH groups in the molecule. (5) In the method for producing a gallium oxide-coated silver powder according to item (3) or (4), it is more preferable that the reducing agent is formaldehyde. In the present invention, there is also provided: (6) The conductive paste using a gallium oxide-coated silver powder according to the item (1) or (2). ADVANTAGEOUS EFFECTS OF INVENTION By using the gallium oxide-coated silver powder of the present invention, even when the silver