PLASMA PROCESSING APPARATUS AND PLASMA PROCESSING METHOD

摘要

Provided are a plasma processing apparatus with a radio-frequency power supply supplying temporally modulated intermittent radio-frequency power which can be controlled with high precision in a wide repetition frequency band, and a plasma processing method using the plasma processing apparatus.;A plasma processing apparatus includes: a vacuum vessel; a plasma generating section plasma in the vacuum vessel; a stage installed in the vacuum vessel and mounted with a sample; and a radio-frequency power supply applying temporally modulated intermittent radio-frequency power to the stage, wherein the radio-frequency power supply has two or more different frequency bands and temporally modulates the radio-frequency power by a repetition frequency which has the same range of analog signals used in each of the frequency band.

主权项

1. A plasma processing apparatus, comprising:
a vacuum vessel in which a sample is plasma treated; a first radio-frequency power supply supplying a first radio frequency power to generate a plasma in the vacuum vessel; a sample stage installed in the vacuum vessel and mounted with the sample; a second radio-frequency power supply supplying a second radio-frequency power to the sample stage; and a D/A converter converting a digital signal into an analog signal, a control unit configured to convert a first digital value which is a value within a first frequency band in a set repetition frequency of a pulse for time-modulating the second radio-frequency power to a first analog value and a second digital value which is a value within a second frequency band wider than the first frequency band in the repetition frequency to a second analog value by the D/A converter; wherein the second radio-frequency power supply includes an A/D converter converting the first analog value and the second analog value transmitted by the control unit to the first digital value and the second digital value each; a signal processing unit configured to select the first digital signal converted by the A/D converter or the second digital value converted by the A/D converter based on a signal received at the A/D converter; and a pulse generator generating pulses having a repetition frequency corresponding to the first digital value or the second digital value selected by the signal processing unit.