| 摘要 |
PURPOSE:To remarkably reduce generation of radioactive particles and eliminate generation of soft error by reducing content of U and Th which is inevitably contained as the impurity to Al alloy ultra fine lead wire to less than 10ppb. CONSTITUTION:A high purity Al with purity of 99.999% including U of 210ppb and Th of 90ppb is used and it is adjusted to the high purity Al with respective contents of U and Th of under 10ppb by executing, once or twice or more, the belt melting refining. As a result, the high purity Al is melted by the vacuum melting method and a kind or two kinds of Si: 0.5-2%, Mg: 0.1-2% (where, Si+Mg: 2% or less) are added as the alloy component thereto. |
