Composition for sintering, method for producing silver nanoparticles, circuit board, and method for manufacturing circuit board
AssigneeStanley Electric Co., Ltd.
InventorsHiroto Fukushima, Akihiko Hanya
Life of this patent
Estimating the term…
Abstract
An object of the present invention is to provide a composition for sintering capable of suppressing a crack from occurring in a wiring after sintering. Provided is the composition for sintering including silver nanoparticles, an organic dispersant for coating the silver nanoparticles, and a solvent. When the composition for sintering is heated, a weight loss rate in a range of 260° C. to 600° C. is 2.92% or less.
Claims21
A composition for sintering, comprising:
- silver nanoparticles;
- an organic dispersant for coating the silver nanoparticles;
- and
- a solvent,
- wherein:
- when the composition for sintering is heated, a weight loss rate in a range of 260° C. to 600° C. is 2.92% or less, and
- when the composition for sintering is subjected to differential thermal analysis, no exothermic peak appears at 350° C. to 500° C.
A circuit board comprising:
- a substrate;
- and
- wiring mounted on the substrate,
- wherein:
- at least a part of the wiring is made of a conductive material obtained by sintering silver nanoparticles,
- the wiring includes voids between the sintered silver nanoparticles and the silver nanoparticles,
- a ratio occupied by the voids in a cross-section of the wiring is 24.0% or less, and
- a sum of peripheral edge lengths of all the voids in a unit area (2500 nm square) of the cross-section of the wiring is 117 nm or more and 331 nm or less.
A circuit board comprising:
- a substrate;
- and
- wiring mounted on the substrate,
- wherein:
- at least a part of the wiring is made of a conductive material obtained by sintering silver nanoparticles,
- the wiring includes voids between the sintered silver nanoparticles and the silver nanoparticles,
- a ratio occupied by the voids in a cross-section of the wiring is 24.0% or less, and
- the ratio occupied by the voids in the cross-section of the wiring is 8.8% or more.
A method for producing silver nanoparticles for a composition for sintering that includes the silver nanoparticles, an organic dispersant for coating the silver nanoparticles, and a solvent, wherein when the composition for sintering is heated, a weight loss rate in a range of 260° C. to 600° C. is 2.92% or less, and wherein when the composition for sintering is subjected to differential thermal analysis, no exothermic peak appears at 350° C. to 500° C., the method comprising:
- depositing the silver nanoparticles coated with the organic dispersant by dropping a silver ion solution containing silver ions into an organic dispersant solution obtained by dissolving the organic dispersant in the solvent,
- wherein by adjusting an amount of the organic dispersant dissolved in the solvent, the silver nanoparticles are produced so that the weight loss rate in the range of 260° C. to 600° C. is 2.92% or less when the composition for sintering is heated.
Dependencies are inferred from the claim text.