摘要 |
<p>A plasma etching method using a plasma etching apparatus including a lower electrode and an upper electrode is provided. The plasma etching method includes a first etching step of performing plasma etching using a first process gas and a second etching step of performing the plasma etching using a second process gas. The adhesion of a radical of the second process gas to an object of processing is less than the adhesion of a radical of the first process gas to the object of processing. While alternately repeating a first condition of turning on high-frequency electric power for plasma generation and a second condition of turning off the high-frequency electric power, the second etching step applies a negative direct-current voltage to the upper electrode so that the absolute value of the applied voltage is greater in a period of the second condition than in a period of the first condition.</p> |