| 摘要 |
PROBLEM TO BE SOLVED: To provide a filter medium of an air filter for filtering process gases in semiconductor device fabrication which has a low pressure loss (a high ventilation capacity), is compact in size and lightweight, and requires no seal material. SOLUTION: A polytetrafluoroethylene (PTFE) porous membrane is used for a filter medium of an air filter for filtering process gases in semiconductor device fabrication. The PTFE porous membrane to be used is preferable to have a collection efficiency of 99.999995 or higher and a pressure loss of 0.2 to 1 kPa. Two or more sheets of the PTFE porous membrane are preferable to be laminated and used without being united with an adhesive or the like. COPYRIGHT: (C)2006,JPO&NCIPI
|
