PLASMA PROCESSING METHOD AND PLASMA ASHING APPARATUS

PROBLEM TO BE SOLVED: To provide a processing method that can prevent or reduce a film damage on a Low-k film while performing a high speed ashing processing in a plasma ashing processing on a sample including a Low-k film.SOLUTION: A plasma processing method for performing a plasma processing on a sample including a Low-k film 15 includes: performing plasma etching on the sample; and performing plasma ashing on the sample including the Low-k film 15 with a resist mask 13, a carbon hard mask 14 and reaction products 16 that have been subjected to plasma etching in the plasma etching process by a carbon (C+) radical 18 and a hydrogen (H+) radical 20 generated from methane (CH) gas 19, using mixed gas including the methane (CH) gas 19, which is hydrocarbon gas, and argon (Ar) gas, which is noble gas.