PURPOSE: To shorten cooling time of a plasma generating chamber by directly striking inert gas blowing off from vent piping on the plasma generating chamber, and discharging the inert gas from the branch tip of discharge piping.
CONSTITUTION: The tip of a signal conductor 32 of a thermocouple 31 connected to a plasma generating chamber 14 is connected to a controller of a high voltage terminal 4. Vent piping 28 and a module chamber 12 for an ion source are connected to each other just under the plasma generating chamber 14, and inert gas blowing off from the vent piping 28 is directly struck on the plasma generating chamber 14. Roughing piping 22 among discharge piping is branched off on this side of a branch point at which a leak valve 27 is arranged, and a valve 34 is arranged in the branch pipe 33. The branch pipe 33 is joined to the downstream side of an exhaust duct 36 connected to a outlet pipe 35 of a pump 24 for a low vacuum.
AIHARA TSUYOSHI
SUZUKI HIDEO
MIYATANI TAKENAO
