| 摘要 |
A method for reducing an internal pressure of a vacuum chamber while preventing impurity contamination within the vacuum chamber as much as possible is provided. The method includes: rough pumping reducing an internal pressure of a vacuum chamber by using a roughing pump, the roughing pump being a mechanical pump that is capable of reducing the internal pressure of the vacuum chamber to be less than 15 Pa; main pumping reducing the internal pressure of the vacuum chamber by using a main pump after the rough pumping, the main pump being a non-mechanical pump. Transition from the rough pumping to the main pumping is performed when the internal pressure of the vacuum chamber is no less than 15 Pa. |
