| 摘要 |
<p>PROBLEM TO BE SOLVED: To quantitatively measure the amount of a leaking gas by utilizing gas flow rate feed performance of a mass flow controller(MFC) and adding a function of replacing and controlling a pressure change mode brought about when the gas is fed to a target value. SOLUTION: A piping 6 is connected to an MFC 12 which supplies a gas with controlling the amount of the gas. A vacuum gauge 13 is set in the halfway to detect an internal pressure of the piping 6 and connected to a gas leak- detecting part 14 via a wiring. When an electrostatic chuck 4 reaches a set temperature after being started to be cooled, a voltage is impressed to a wafer 15 and the electrostatic chuck 4 to attract the wafer 15. A flow rate when a pressure in a gas feed path is maintained and continues is the amount of the leaking gas to be detected. Therefore, a control part is provided in which a constant pressure control function is added to a constant flow rate control function which is a function of the MFC 12. When a target pressure is set at the gas leak-detecting part 14 and the detecting part 14 is driven, the amount of the leaking gas at the set pressure is detected.</p> |
