| 摘要 |
PURPOSE:To improve reliability by manufacturing a high-purity Pb material so as to satisfy conditions of purity of 99.999% or more, the content of radioactive isotopes of less than 5ppb and the count number of radioactive alpha particles of 0.09CPH/cm<2> or less. CONSTITUTION:A raw material having high purity of 99.999% or more and properties of the content of radioactive isotopes of less than 5ppb and the count number of radioactive alpha particles of 0.09CPH/cm<2> or less is used for a Pb alloy solder material. Accordingly, when the solder material is employed for brazing joining with a ceramic case 1 of a sealing board 4 for a device such as an IC, the memory errors of the IC after assembly are eliminated completely, thus improving reliability. |
