Dowa Electronics Materials Co., Ltd.

Keiichi Endoh

Satoru Kurita

Toshihiko Ueyama

Hiromasa Miyoshi

Yutaka Hisaeda

Akihiro Miyazawa

Minami Nagaoka

Aiko Nagahara

Takashi Hinotsu

Aiko Hirata

Yoshiko Kohno

Tatsuro Hori

Yu Saito

Kimikazu Motomura

Hideyuki Fujimoto

Koichi Yuzaki

Minami Kanasugi

In a bonding material of a metal paste containing metal particles, a solvent and a dispersant, the metal particles containing first metal particles having an average primary particle diameter of 1 to 40 nm, second metal particles having an average primary particle diameter of 41 to 110 nm, and third metal particles having an average primary particle diameter of 120 nm to 10 μm, the weight percentages of the first, second and third metal particles being 1.4 to 49% by weight, 36% by weight or less, and 50 to 95% by weight, respectively, with respect to the total 100% by weight of the metal particles, and the weight ratio of the first metal particles to the second metal particles being 14/36 or more.

Bonding material and bonding method using same

There are provided a bonding material, which can prevent voids from being generated in a silver bonding layer by preventing the entrainment of bubbles during the formation of a coating film even if the coating film is thickened, and a bonding method using the same. The bonding material of a silver paste includes fine silver particles, a solvent and an addition agent, wherein the solvent contains a first solvent of a diol, such as octanediol, and a second solvent which is a polar solvent (preferably one or more selected from the group consisting of dibutyl diglycol, hexyl diglycol, decanol and dodecanol) having a lower surface tension than that of the first solvent and wherein the addition agent is a triol.

Joining material and joining method using same

A bonding material includes: fine silver particles having an average primary particle diameter of 1 to 50 nm, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as hexanoic acid; silver particles having an average primary particle diameter of 0.5 to 4 &#x3bc;m each of the silver particles being coated with an organic compound, such as oleic acid; a solvent containing a primary alcohol solvent and a terpene alcohol solvent; and a dispersant containing a phosphoric acid ester dispersant (or a phosphoric acid ester dispersant and an acrylic resin dispersant), wherein the content of the fine silver particles is in the range of from 5 wt % to 30 wt %, and the content of the silver particles is in the range of from 60 wt % to 90 wt %, the total content of the fine silver particles and the silver particles being not less than 90 wt %, and wherein the bonding material further includes a sintering aid of a monocarboxylic acid having an ether bond.

There is provided an inexpensive bonding material, which can be easily printed on articles to be bonded to each other and which can suppress the generation of voids in the bonded portions of the articles to be bonded to each other, and a bonding method using the same. In a bonding material of a copper paste which contains a copper powder containing 0.3% by weight or less of carbon and having an average particle diameter of 0.1 to 1 &#x3bc;m, and an alcohol solvent, such as a monoalcohol, a diol, a triol or a terpene alcohol, the content of the copper powder is in the range of from 80% by weight to 95% by weight, and the content of the alcohol solvent is in the range of from 5% by weight to 20% by weight.

A bonding material of a silver paste contains: fine silver particles having an average primary particle diameter of 1 to 200 nm, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as sorbic acid; and a solvent mixed with the fine silver particles, wherein a diol, such as an octanediol, is used as the solvent and wherein a triol having a boiling point of 200 to 300&#xb0; C., a viscosity of 2,000 to 10,000 mPa&#xb7;s at 20&#xb0; C. and at least one methyl group, such as 3-methylbutane-1,2,3-triol or 2-methylbutane-1,2,4-triol, is mixed with the solvent as an addition agent.

A bonding material of a silver paste includes: fine silver particles having an average primary particle diameter of 1 to 50 nanometers, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as hexanoic acid; silver particles having an average primary particle diameter of 0.5 to 4 micrometers, each of the silver particles being coated with an organic compound, such as oleic acid; a solvent containing 3 to 7% by weight of an alcohol and 0.3 to 1% by weight of a triol; a dispersant containing 0.5 to 2% by weight of an acid dispersant and 0.01 to 0.1% by weight of phosphate ester dispersant; and 0.01 to 0.1% by weight of a sintering aid, such as diglycolic acid, wherein the content of the fine silver particles is in the range of from 5% by weight to 30% by weight, and the content of the silver particles is in the range of from 60% by weight to 90% by weight, the content of the total of the fine silver particles and the silver particles being not less than 90% by weight.

A method of bonding two different substances includes the steps of: applying a bonding material containing a flux component that includes an organic material having at least two carboxyl groups to a bonding surface of a bonding object, disposing an object to be bonded on the bonding material, performing preliminary firing at a preset temperature in a state in which the object to be bonded is disposed, and performing a main firing by heating at a temperature higher than the temperature of the preliminary firing.

Bonding method using bonding material

A bonded product is obtained by applying a silver paste containing silver nanoparticles having an average primary particle diameter of 1 to 200 nm, and performing firing. A diameter of a crystallite of the bonded product on a (111) plane of Ag when heated at 250&#xb0; C. for 10 minutes in an inert atmosphere is 65 nm or larger.

Bonding material and bonding method using the same

There is provided a metal nanoparticle dispersion which can be bonded at a lower temperature (for example, 200&#xb0; C. or less), and enabling to obtain excellent mechanical properties and electric properties of the bonded portion, the metal nanoparticle dispersion, including: metal nanoparticles, with at least a part of a surface of each particle coated with amine A having 8 or more carbon atoms; and a dispersion medium for dispersing the metal nanoparticles, wherein the dispersion medium contains amine B which is primary, secondary, or tertiary amine having 7 or less carbon atoms, and which is linear alkyl amine or alkanol amine.

Metal nanoparticle dispersion, method for producing metal nanoparticle dispersion, and bonding method

The occurrence of uneven drying in the center and end of a surface of a bonding layer during a desolvation process of a pre-drying step is reduced to ensure highly reliable bonding without peeling of a bonding surface even after repeated exposure to heat shock after bonding. The bonding material of the present invention to achieve the object contains silver nanoparticles coated with organic substance having 6 or less carbon atoms and having an average primary particle diameter of 10 to 30 nm as main silver particles, silver nanoparticles coated with an organic substance having 6 or less carbon atoms and having an average primary particle diameter of 100 to 200 nm as secondary silver particles, two kinds of solvents having different boiling points, and a dispersant.

Bonding material and bonding method in which said bonding material is used

There is provided a bonding material capable of forming a bonding body under an inert gas atmosphere such as a nitrogen atmosphere, and capable of exhibiting a bonding strength that endures a practical use even if not a heat treatment is applied thereto at a high temperature, which is the bonding material containing silver nanoparticles coated with a fatty acid having a carbon number of 8 or less and having an average primary particle size of 1 nm or more and 200 nm or less, and silver particles having an average particle size of 0.5 &#x3bc;m or more and 10 &#x3bc;m or less, and an organic material having two or more carboxyl groups.

Bonding material and bonding body, and bonding method

A method of forming a bonded product using metal nanoparticles is provided. More specifically, provided is a paste containing a flux component that can form a metal phase even in an inert atmosphere. The use of this paste allows a bonding material that can give a practically acceptable bonding strength to be provided in an inert atmosphere such as a nitrogen atmosphere at low temperatures without performing conventionally used pressurization. The paste is a bonding material configured to include: silver nanoparticles having an average primary particle diameter of 1 to 200 nm and coated with an organic material having 8 or less carbon atoms; a flux component having at least two carboxyl groups; and a dispersion medium. The use of this bonding material allows materials to be bonded even at a temperature of 300&#xb0; C. or lower.

In a bonding material using nanoparticles and a bonding method, use in combination with microparticles is proposed. However, there is the problem in which it is not easy to uniformly mix the nanoparticles and the microparticles. The present invention uses a bonding material including metal nanoparticles having an average particle diameter of 100 nm or less and a surface coated with an organic substance having 6 to 8 carbon atoms, and a polar solvent in an amount of 5 to 20% by mass with respect to a powder of the metal nanoparticles, and objects to be bonded with the bonding material interposed therebetween are fired at 200 to 350&#xb0; C. under pressure. Thus, the metal nanoparticles are melted and returned to a bulk material, and therefore a bonding layer of the bulk material can be formed at a low temperature equal to or lower than a melting point.

Bonding material using metal nanoparticles coated with C6-C8 fatty acids, and bonding method

Provided is a bonding material which enables formation of a bonded article in nitrogen, and can exhibit bonding strength to withstand practical use while having reduced bonding fluctuations between samples without a heat treatment procedure under pressurized or high temperature conditions. The bonding material comprises: silver nanoparticles having an average primary particle diameter of 1 to 200 nm and coated with an organic substance having 8 carbon atoms or less; a dispersion medium having a boiling point of 230&#xb0; C. or higher; and a flux component including an organic matter having at least two carboxyl groups. Particularly, it is preferable to use the silver nanoparticles and submicron silver particles in combination.

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Okayama, Japan

Keiichi Endoh