Patent attributes
An etching processing method for etching a substrate formed with a target film and a mask film is performed in a substrate processing apparatus including a first and a second power supply for respectively supplying a higher and a lower high frequency power to a processing space and a mounting table, and a DC power supply for supplying a DC power to an electrode. The method includes a modification step for modifying a shape of a pattern formed on the mask film; and an etching step for etching the target film by using the mask film. The mask film is etched by the plasma in the modification step. Further, in the etching step, the DC power is applied to the electrode and the lower high frequency power is applied to the mounting table in a pulse wave form in which a higher and a lower power level are repeated.