Senju Metal Industry Co., Ltd.

Lenovo (singapore) Pte. Ltd.

Lenovo Limited

Tetsu Takemasa

Ryo Saito

Tadashi Kosuga

Kazuyori Takagi

Tomoko Nagai

Nanako Miyagi

Ko Inaba

Yutaka Hashimoto

Mutsuki Kaneko

Megumi Hayakawa

Tsuyoshi Masaki

Minoru Ueshima

Jinting Jiu

Junko Seino

A flux containing rosin, a solvent, a thixotropic agent, a thiol compound, and an activator, in which the thiol compound includes a compound (Tp) having a benzenethiol skeleton in which one or more hydrogen atoms on a benzene ring are substituted with a mercapto group (—SH), is provided in the present invention. As the compound (Tp), at least one thiol compound selected from the group consisting of 2-aminobenzenethiol, 4-aminobenzenethiol, 3-aminobenzenethiol, and benzenethiol is preferable. According to such flux, a change in viscosity of the solder paste with time can be further suppressed.

Flux and solder paste

A flux containing rosin, a solvent, a thixotropic agent, an amine hydroiodide, and an activator (provided that the amine hydroiodide is excluded), in which the amine hydroiodide includes a heteroalicyclic amine hydroiodide, is provided in the present invention. As the heteroalicyclic amine hydroiodide, at least one selected from the group consisting of piperidine hydroiodide and pipecholine hydroiodide is preferable. According to such flux, the generation of voids during soldering can be further suppressed.

An object of the present invention is to provide an electrically conductive paste and a sintered body thereof having a low electric resistance value and excellent electrical conductivity when made into a sintered body. An electrically conductive paste comprising: a flake-like silver powder having a median diameter D50 of 15 &#x3bc;m or less; a silver powder having a median diameter D50 of 25 &#x3bc;m or more; and a solvent,

Electrically conductive paste and sintered body

A solder joint, for bonding an electrode of a circuit board to an electrode of an electronic component, that includes: an Sn&#x2014;Bi-based solder deposited on the electrode of the circuit board; and a solder alloy deposited on the electrode of the electronic component. The Sn&#x2014;Bi-based solder alloy has a lower melting point than the solder alloy deposited on the electrode of the electronic component. Fine Bi phases in the solder joint each have an area of less than or equal to 0.5 &#x3bc;m. Coarse Bi phases in the solder joint each have an area of greater than 0.5 &#x3bc;mand less than or equal to 5 &#x3bc;m. A proportion of the fine Bi phases among the fine Bi phases and the coarse Bi phases is greater than or equal to 60%.

Solder joint

A solder bonding method that bonds, using a solder joint, an electrode of a circuit board to an electrode of an electronic component includes: depositing, on the electrode of the circuit board, an Sn&#x2014;Bi-based solder alloy with a lower melting point than a solder alloy deposited on the electrode of the electronic component; mounting the electronic component on the circuit board such that the Sn&#x2014;Bi-based solder alloy contacts the solder alloy on the electrode of the electronic component; heating the circuit board to a peak temperature of heating of 150&#xb0; C. to 180&#xb0; C.; holding the peak temperature of heating at a holding time of greater than 60 seconds and less than or equal to 150 seconds; and cooling, after the heating and to form the solder joint, the circuit board at a cooling rate greater than or equal to 3&#xb0; C./sec.

Solder bonding method and solder joint

A metal sintered bonding body bonds a substrate and a die. In the metal sintered bonding body, at least a center part and corner part of a rectangular region where the metal sintered bonding body faces the die have a low-porosity region whose porosity is lower than an average porosity of the rectangular region. The low-porosity region is located within a strip-shaped region whose central lines are diagonal lines of the rectangular region.

Growing community of inventors

Tokyo, Japan

Tetsu Takemasa