Harima Chemicals, Incorporated

The Furukawa Electric Co., Ltd.

Seishi Kumamoto

Takahiro Fujiwara

Toshiaki Amano

Takao Fukunaga

Hisao Irie

Hirokazu Shiroishi

Takaaki Anada

Hitoshi Sakurai

Youichi Kukimoto

Kenshu Oyama

Kazuhito Hikasa

Eiichiro Matsubara

Kazuhito Higasa

Tetsu Ichitsubo

Noriko Katayama

The present invention is a method to manufacture the SnZnNiCu solder powder through liquid quenching atomizing method, and an atomizing temperature is not less than 500&#xb0; C., in particular, not less than 900&#xb0; C. The raw material metal used as raw material of the solder powder comprises 3 to 12% by weight of Zn, 1.0 to 15% by weight of the sum of Cu and Ni, and Sn and inevitable impurities for the rest, to the total amount of raw material. Thereby, high joint strength is achieved and the SnZnNiCu solder powder which can improve joint reliability of solder joint part is provided.

Method of manufacturing the SnZnNiCu solder powder and the SnZnNiCu solder powder

The present invention provides a solder deposition method that includes the step of forming a dam around an electrode on a substrate, the step of applying a solder precipitating composition to the substrate, and the step of depositing solder on the surface of the electrode while heating the solder precipitating composition applied. This solder deposition method is suitable for forming large bumps at fine pitches. In particular, it is capable of depositing solder in a desired height precisely and easily, and yet preventing occurrence of voids.

Solder deposition method and solder bump forming method

Solder-precipitating composition and mounting method using the

A large number of pads, to which component leads are to be soldered, are formed on an insulating substrate so as to constitute a pad array. Colder layers are precoated on the pads. Each of the pads has a component lead mounting portion where a component lead is to be mounted, and a component lead non-mounting portion where no component lead is to be mounted. The component lead non-mounting portion includes a wide part having a width greater than that of the component lead mounting portion.

Circuit board to be precoated with solder layers and solder circuit board

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Kakogawa, Japan

Seishi Kumamoto