| 摘要 |
<p>PROBLEM TO BE SOLVED: To maintain silicon wafers at the same cleanliness as that when the wafers are manufactured without causing pinholes in the welded sections of resin-made packing bags at the time of transporting wafer product cases by specifying the atmospheric pressures in the packing bags. SOLUTION: The atmospheric pressures in packing bags are adjusted within a range of 0.90-0.99 atm, preferably, 0.95-0.99 atm. Various kinds of resins can be used for the packing bags, but an aluminum-coated polyester which is coated with aluminum so as to prevent moisture from getting in polyester that discharges a little amount of material, can resist friction, and can be welded is preferable. After one bag containing product cases is set on a sealer machine and the inside of the bag is deaerated with a pump, the mouth of the bag is welded. Therefore, silicon wafers can be transported in clean states even when the bag is transported by air, because no pinhole occurs in the welded section and the fluctuation of humidity with time can be suppressed.</p> |
