Patent ID: 8557709

Claim:
A plasma processing method in which a wafer to be processed is mounted on the top surface of a sample stage arranged in a lower portion of a processing chamber, the processing chamber being disposed inside a decompressed vacuum chamber and plasma is generated using a process gas supplied into said processing chamber through introduction holes arranged above said sample stage to perform an etching process of etching a film structure disposed on a surface of said wafer, said film structure being constituted by having a resist film or a mask film, a poly-silicon film and an insulation film laminated in this order from top to bottom on a substrate of said wafer, the method comprising: a step of covering a surface of members inside the processing chamber with a coating film containing a component of Si, using plasma generated within said processing chamber by a gas for coating which is supplied into said processing chamber; a step of, after said step of covering, performing aftertreatment of the coating film in a manner that projections, unevenness and roughness of a surface of the coating film are decreased, using plasma generated within said processing chamber by a gas for aftertreatment which is supplied into said processing chamber; and a step of, after said step of performing aftertreatment, etching said film structure in a manner that said poly-silicon film underlying said mask film on the surface of said wafer is etched.