SUBSTRATE PROCESSING METHOD

摘要

There is provided a substrate processing method capable of preventing the decrease in etching efficiency by positive ions and increasing the overall etching efficiency by using negative ions. The substrate processing method includes applying a plasma RF and a bias RF in the pattern of a pulse wave, respectively. The substrate processing method repeatedly performs the steps of: (3b) etching a substrate by positive ions in plasma by applying both the plasma RF and the bias RF; (3c) generating negative ions in a processing chamber by stopping the application of both the plasma RF and the bias RF; and (3a) attracting the negative ions to the substrate by applying the bias RF and stopping the application of the plasma RF. A duty ratio of the bias RF is set to be greater than a duty ratio of the plasma RF.