| 摘要 |
Tin characterized in that a melted and casted sample thereof has an a-dose less than 0.0005 cph/cm2. With the recent tendency toward high-density and high-capacity semiconductor devices, the risk of soft errors caused by a-rays emitted from materials, which are located in the neighborhood of semiconductor chips, is increasing. Thus, it is strongly required to elevate, in particular, the purity of solder materials or tin which are to be positioned closely to semiconductor devices in using. Also, materials with little a-rays are required. Under these circumstances, the phenomenon of a-ray emission from tin and tin alloys is clarified and highly pure tin, i.e., tin having reduced a-dose, which is usable in such required materials as described above, and a method of producing the same are disclosed. |
