Senju Metal Industry Co., Ltd.

Takashi Yashima

Hiroyoshi Kawasaki

Takahiro Roppongi

Daisuke Soma

Hiroki Sudo

Masato Tsuchiya

Shigeki Kondoh

The Cu core ball contains a Cu ball and a solder layer for covering a surface of the Cu ball. The Cu ball contains at least one element selected from Fe, Ag, and Ni in a total amount of 5.0 or more to 50.0 ppm by mass or lower, S in an amount of 0 or more to 1.0 ppm by mass or lower, P in an amount of 0 or more to less than 3.0 ppm by mass, and remainder of Cu and inevitable impurities. The Cu ball contains purity which is 99.995% or higher and 99.9995% by mass or lower, and sphericity which is 0.95 or higher. The solder layer includes Ag in an amount of more than 0 to 4.0% by mass or less, Cu in an amount of more than 0 to 3.0% by mass or less, and remainder of Sn.

Cu core ball, solder joint, solder paste and formed solder

The Cu core ball contains a Cu ball and one or more metal layer for covering a surface of the Cu ball, each layer including one or more element selected from Ni, Co, Fe and Pd. The Cu ball contains at least one element selected from Fe, Ag, and Ni in a total amount of 5.0 or more to 50.0 ppm by mass or lower, S in an amount of 0 ppm by mass or more to 1.0 ppm by mass or lower, P in an amount of 0 ppm by mass or more to less than 3.0 ppm by mass, and remainder of Cu and inevitable impurities. The Cu ball contains purity which is 99.995% by mass or higher and 99.9995% or lower, sphericity which is 0.95 or higher and a diameter of 1 &#x3bc;m or more to 1000 &#x3bc;m or lower.

Growing community of inventors

Tochigi, Japan

Takashi Yashima