Patent ID: 6987271

Claim:
A chamber sensor port which connects a sensor for measuring a physical quantity inside a chamber to an inside of the chamber, the sensor being installed on an outside of a wall of the chamber, the chamber sensor port comprising: a port attachment opening formed by running through the wall of the chamber; a first block airtightly installed at an inside of the port attachment opening and including one or more first through holes running through in a direction of an axis of the port attachment opening; a second block airtightly installed at the inside of the port attachment opening, the second block being disposed adjacent to an axially outer surface of the first block and including one or more second through holes running through in the direction of the axis of the port attachment opening, the second through holes being disposed at locations not overlapping with those of the first through holes and communicating with the first through holes through a gap formed between the first and the second block; a third block airtightly installed between the first block and the second block and including one or more third through holes running through in the direction of the axis of the port attachment opening, the third through holes being disposed at locations not overlapping with those of the first and the second through holes and communicating with the first and the second through holes through a gap formed between the first block and the third block and a gap formed between the second block and the third block, respectively.