| 摘要 |
An observation window airtightly installed at a wall of a processing room of a plasma processing apparatus includes a body having a through hole with an opening facing the processing room, a transparent member installed at a side of the body opposite to the processing room and a magnetic pole pair having two different magnetic poles disposed opposite each other with the hole interposed therebetween. The magnetic pole pair is configured to have a sufficient magnetic field strength to prevent electrons which form a plasma in the processing room from reaching the transparent member through the hole. |
