| 摘要 |
PROBLEM TO BE SOLVED: To eliminate influence of a gas flow to make the ashing process uniform without rotating a stage, by feeding a process gas in a closed process chamber, holding the pressure constant in this chamber, and exhausting after a fixed time. SOLUTION: In a process chamber a heater stage 4 for heating a wafer 3 and a UV lamp 6 for providing rays at a wavelength of nearly 254 nm are installed, and when a process gas is fed to the process chamber through a three-way valve 8, a valve 9 is closed. When the pressure shown by a manometer 10 reaches a desired value, the three-way valve 8 is switched for exhaustion, the valve 9 remains closed to thereby holding a fixed pressure in the process chamber. After a predetermined time lapsed, the valve 9 opens to exhaust the process chamber, the valve 9 is closed again when a set pressure value is reached in the process chamber, and the three-way valve 8 is switched for gas feeding to the process chamber, thereby processing at a fixed pressure. The above process sequence is repeated to do the ashing process. |
