Plasma processing method

摘要

A plasma processing method in which a stable process region can be ensured in a wide range, from low microwave power to high microwave power. The plasma processing method includes making production of plasma easy in a region in which production of plasma by continuous discharge is difficult, and plasma-processing an object to be processed, with the generated plasma, wherein the plasma is produced by pulsed discharge in which ON and OFF are repeated, radio-frequency power for producing the pulsed discharge, during an ON period, is a power to facilitate production of plasma by continuous discharge, and a duty ratio of the pulsed discharge is controlled so that an average power of the radio-frequency power per cycle is power in the region in which production of plasma by continuous discharge is difficult.

主权项

1. A plasma processing method of etching a wafer using plasma, comprising the steps of:
ON-OFF modulating a radio-frequency power for generating plasma; setting a power during ON of the ON-OFF modulated radio-frequency power to a power value in a region in which plasma instability does not occur when generating plasma by continuous discharge; and controlling a duty ratio of the ON-OFF modulation such that a product of the power during ON of the ON-OFF modulated radio-frequency power which is set to a power value in a region in which plasma instability does not occur when generating plasma by continuous discharge, and the duty ratio of the ON-OFF modulation, becomes a power value in a region in which plasma instability occurs when generating plasma by continuous discharge.