Patent ID: 8114244

Claim:
A method for plasma processing, using a plasma processing apparatus comprising a vacuum processing reactor constituting a vacuum processing chamber, a gas supply device for supplying processing gas into the vacuum processing reactor, a plasma generating means for dissociating the processing gas supplied via the gas supply device and generating plasma, an emission spectroscope for monitoring the emission of plasma generated via the plasma generating means, and a means for storing the emission spectrum thereof, to perform an etching process of a sample carried into the vacuum processing reactor, wherein the method comprises: a first cleaning step for plasma cleaning inside the vacuum processing reactor after the etching process of the sample; an idling of the etching process, wherein during the idling the etching process of the sample is temporarily discontinued; a second cleaning step for plasma cleaning inside the vacuum processing reactor after the idling; and a heating step for plasma heating the vacuum processing reactor after the idling and before restarting the etching process of the sample, wherein in the heating step, the vacuum processing reactor is plasma heated until a difference between an emission intensity during the first cleaning step and an emission intensity during the second cleaning step becomes substantially zero, or a ratio between an emission intensity during the first cleaning step and an emission intensity during the second cleaning step becomes substantially one.