METHOD OF REMOVING EXHAUST GAS

摘要

PURPOSE: A method is provided to prevent residual exhaust gas from being leaked outside a process chamber when opening a chock or a door of the process chamber by pumping after completely removing the residual exhaust gas in the process chamber. CONSTITUTION: A door or a chock is closed after loading a semiconductor wafer into a process chamber from a loading unit. And, pumping is operated to decrease the pressure of the process chamber to certain degree. A high frequency generator is turned on after injecting process gas into the process chamber. Then, the high frequency generator is switched off, and a gas injection valve is locked. Nitrogen gas(125) is slowly purged into the process chamber by employing a delay valve(128) for being pumped at the maximum. And, the semiconductor wafer is exhausted from the process chamber after secondarily slow-purging the nitrogen gas again.