PLASMA CLEANING METHOD

PURPOSE:To improve cleaning speed by supplying O2+SF6 or a mixture gas of O2+SF6 as cleaning gas, and generating a plasma in the cleaning gas. CONSTITUTION:CHF3 is introduced from an etching gas source 2 into a treating chamber 1, a high frequency power is applied by a high frequency power source 5 to a lower electrode 4 to generate a plasma in etching gas. Thus, an SiO2 film is etched. Then, in order to remove reactive products adhered and deposited in the chamber 1, cleaning gas is introduced from a cleaning gas source 6 into the chamber 1, a high frequency power is applied to the electrode 4 similarly to the time of etching to generate a plasma in the cleaning gas. In this case, 4 types of gases added as additive gases of SF6, CF4, N2 or CHF3 to O2 are employed as the cleaning gas to obtain a higher cleaning speed than that in case of heretofore plasma cleaning with O2.