| 摘要 |
PURPOSE:To screen alpha rays as well as to obtain the memory device of high integration by a method wherein a resin type material, containing the total quantity of U and Th of 1ppb or below and 0.2ppb or above, is interposed between a memory element and a sealing material. CONSTITUTION:A filler is mixed in a resin type material of polymer such as synthetic resin, natural resin, synthetic rubber or natural rubber and the like in order to improve the physical characteristics and the total quantity of the U and the Th is maintained at 1ppb or below and 0.2ppb or above for easy performance of refining. The oxide and nitride of an organic metal compound are suitable for the filler of high purity, and especially, the contents of the U and the Th of the oxide is much smaller than that of natural substance which is used in general. The above is dissolved or suspended by resin varnish, a surface active agent is added when necessary, and a film of 40mum in thickness is formed. According to this constitution, a soft error can be prevented, and the film is effective for a low integration memory even when the thickness of which is thinner than 30mum. |
